ANTARES MDT Owner’s Manual

Download

MDT

Multiband Dynamics Toolª

for TDM

™

UserÕs Manual

v 4.4

MDT UserÕs Manual

MDT – Multiband Dynamics Tool™

Antares Audio Technologies 464 Monterey Ave, 2nd Floor Los Gatos, CA, 95030 (408) 399-0008, (888) 332-2636 web: www.antaresTech.com

MDT Ð Multiband Dynamics Tool software and this user manual are protected by copyright law. Making copies, adaptations, or derivative works without prior written authorization of Antares Audio Technologies, is prohibited by law and constitutes a punishable violation of the law.

Antares Audio Technologies retains all ownership rights to the MDT software and other software offered by Antares Audio Technologies and their documentation. Use of MDT is limited by the license agreement printed on the envelope containing your original diskette.

All trademarks are the property of their respective holders.

MDT License Agreement

MDT UserÕs Manual

Carefully read all the terms and conditions of this license agreement. If you do not agree with the terms and conditions of this Agreement, notifying Antares Audio Technologies and destroying all copies of the manual, and erasing MDT from all machine-readable media, whether on-line or on archival copies.

Software License Agreement

Antares Audio Technologies grants you a non-transferable, non-exclusive license to use MDT, under the terms and conditions stated in this agreement. Use of MDT indicates your agreement to the following terms and conditions.

License

You may:

1. use MDT on only one computer at a time;

2. physically transfer the program from one computer to another, provided that the program is used on only one computer at a time.

You may not:

1. make copies of MDT or of the user manual in whole or in part except as expressly provided for in this agreement. Your right to copy MDT and the user manual is lim-

ited by copyright law. Making copies, verbal or media translations, adaptations, derivative works, or telecommunication data transmission of MDT without prior written authorization of Antares Audio Technologies, is prohibited by law and constitutes a punishable violation of the law.

2. make alteration or modifications to MDT (or any copy) or disassemble or de-compile MDT (or any copy), or attempt to discover the source code of MDT.

3. sub license, lease, lend, rent, or grant other rights in all or any portion of MDT (or any copy) to others.

Term of the Agreement

This agreement is effective until terminated by you or Antares Audio Technologies. You may terminate the agreement at any time by notifying Antares Audio Technologies and destroying all copies of the manual, and erasing MDT from all machine-readable media, whether on-line or on archival copies.

In the event of breach of any of the terms of this agreement, you shall pay the attorney's fees of Antares Audio Technologies that are reasonably necessary to enforce the agreement plus resulting damages.

Limited Warranty and Disclaimer

MDT AND ACCOMPANYING MATERIALS ARE PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

Antares Audio Technologies does not warrant that the functions contained in the program will meet your requirements. The entire risk as to the use, quality, and performance of MDT is with you. Antares Audio Technologies warrants the diskettes on which the program is furnished to be free from defects in materials and workmanship under normal use for a period of ninety (90) days from the day of delivery to you as evidenced by a copy of your receipt. AnTares System's entire liability and your exclusive remedy as to the diskettes will be the replacement of the diskettes.

SOME JURISDICTIONS DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU. THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS. YOU MAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM JURISDICTION TO JURISDICTION.

Limitation of Liability

IN NO EVENT WILL ANTARES AUDIO TECHNOLOGIES BE LIABLE FOR ANY DAMAGES, INCLUDING LOSS OF DATA, LOST PROFITS OR OTHER SPECIAL, INCIDENTAL, CONSEQUENTIAL OR INDIRECT DAMAGES ARISING FROM THE USE OF MDT OR ACCOMPANYING MATERIALS. THIS LIMITATION WILL APPLY EVEN IF ANTARES AUDIO TECHNOLOGIES OR ITS AUTHORIZED AGENT HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. YOU ACKNOWLEDGE THAT THE LICENSE FEE REFLECTS THIS ALLOCATION OF RISK. SOME JURISDICTIONS DO NOT ALLOW LIMITATION OR EXCLUSION OF LIABILITY FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU.

MDT UserÕs Manual

iii

Welcome!

I would like to extend my congratulations to you on purchasing the most powerful dynamics processing tool available. With your purchase of MDT, you have created a relationship with my company which I hope will be long and gratifying.

As a registered user of MDT, you are entitled to notiÞcation of software upgrades, technical support, and to special introductory offers on upcoming products. We will be in contact with you to announce new opportunities and to solicit your feedback.

At Antares Audio Technologies, we are committed to excellence in service, quality, and technology innovation. You can count on us to listen to you and to keep our promises to you.

Andy Hildebrand, Ph.D.

andy@antaresTech.com

MDT UserÕs Manual

Table of Contents

CHAPTER 1

CHAPTER 2

Welcome!

Table of Contents

Getting Started

How To Use This Manual

For Those Who Hate To Read Manuals… The Contents Of The Manual

Software Notes

Owner Registration

Installing MDT

Technical Support

Introducing MDT

Understanding Compression

Ratio And Threshold 14 MDT As A Compressor 15 The In/Out Grid 16

“Soft Knee” Compressor “Tube” Compander

Attack And Release Times 19

9 10

17 18

CHAPTER 3

MDT In The TDM Environment

MDT Tutorial

Lesson 1: MDT Basics

About DSP Plug-ins 22 The Peak Level Indicator 22 The I/O Curve 23

MDT UserÕs Manual

The In/Out Grid 25 The Input Offset Arrows 27 The Setting Menu 28

Lesson 2: Single Band Applications

Compressor 30 Attack and Release Times 31 Expander/Gate 34 ÒTubeÓ Compander 36

Example 1: “Soft Knee” comp/gate Example 2: “tube” comp/gate Example 3: Full mix

Lesson 3: Multiband Applications

Multiband Peak Level Indicators 39 The Filter Modes 40 Multiband Compressor 40 Managing Tonal Balance In Multiband Mode 42

What is the Tonal Balance Problem? How To Achieve Tonal Balance

MDT As A Spectral Enhancer 45

De-esser Spectral Enhancer Dynamic EQ

Lesson 4: Clip Sentry

36 37 38

42 43

45 46 47

MDT UserÕs Manual

CHAPTER 4

Lesson 5: Using Automation

New Possibilities 51

Inverted Gain Curves

MDT Reference

Attack Slider 53 Automation 53 Bypass Button 54 Clip Sentry Button 54 Clip Sentry Buf Len (mS) slider 55

Table of Contents

Clip Sentry Release (mS) slider 55 Clipping Indicator 55 Control Surface Support 56 Delay Window 56 Filter Mode Menu 56 Flat Button 58 Gain Slider 58 Input Offset Arrows 58 In/Out Display 59 In/Out Grid 59 Release Slider 61 Reset Button 61 Setting Menu 61 TDM Settings and the Compare Button 62 Thresholds And Terminators 63 Variable Button 63

CHAPTER 5

Theory of Operation

The Gain Adjust Algorithm

The ÒFull BandÓ Filter Mode

The ÒStandardÓ Filter Modes

The ÒAPÓ Filter Modes

Clip Sentry

Stereo Sound Processing

MDT UserÕs Manual

vii

viii

MDT UserÕs Manual

CHAPTER 1

Getting Started

The Multiband Dynamics Tool is a unique DSP plug-in for DigidesignÕsª TDM system that provides unprecedented control over the dynamics of your recordings. Unlike existing dynamics processors, MDT allows the sound to be shaped interactively, giving you creative possibilities never before available.

MDT can create compressors, limiters, expanders, downward expander/ gates, Òsoft kneeÓ compressor/limiters, ÒtubeÓ companders, or any combination of these. In multiband mode, MDT can create de-essers, spectral enhancers, and dynamic EQs, as well as compressors, and expanders that suppress the effects of artifacts like ÒbreathingÓ and ÒpumpingÓ.

MDT replaces expensive digital dynamics processors in applications like mastering, track sweetening, sound effects, sample editing, or any other application where high end digital dynamics processing is needed.

How To Use This Manual

MDT has a transparent user interface and is extraordinarily easy to use. However, the operation of MDT and some functions of the user interface will not be immediately obvious because they do things which have never been done before. We strongly recommend that you read chapters 2 and 3 of the manual to take full advantage of the quality and control that MDT makes possible.

We assume that you already know how to operate ProTools and TDM. If you have questions about this, refer to your ProTools manual or call Digidesign for technical support.

MDT UserÕs Manual

Getting Started

For Those Who Hate To Read ManualsÉ

We strongly recommend that you work your way through the MDT Tutorial in Chapter 3. It doesnÕt take very long and the work will pay for itself many times over. If you canÕt bring yourself to go through the tutorial, we recommend that you keep the manual nearby as you work with MDT. When something puzzling comes up, you can look it up in the Index.

The Contents Of The Manual

Chapter 1: Getting Started

This chapter explains everything about installing MDT, communicating with Antares Audio Technologies, and using the manual.

Chapter 2: Introducing MDT

This chapter explains the scope of MDTÕs functions. Basic concepts about dynamics processing are also covered. The user interface is explained.

Chapter 3: MDT Tutorial

The MDT Tutorial guides you through a step by step process which shows you how to use MDT in various single band and multiband applications. We recommend this chapter as ÒmustÓ reading for everyone.

MDT UserÕs Manual

Chapter 4: MDT Reference

This chapter explains every object and function in MDT. Items are organized in alphabetical order by name.

Chapter 5: Theory of Operation

This chapter explains, in technical terms, how MDT works.

Software Notes

MDT 4.0t is a Digidesign TDM compatible plug-in. It runs with ProTools version 3.2 or greater with TDM installed or any other system capable of running TDM plug-ins.

Owner Registration

Your purchase of MDT entitles you to technical support, special introductory offers on new products from Antares Audio Technologies, and notiÞcation of software updates. Software updates will be published as the program evolves.

Please Þll out and return the Owner Registration Card. The information on the card will allow us to communicate more effectively with you and will enable us to serve you better in the future.

Installing MDT

To install MDT, double click the installer icon. Information about the authorization process call be found in the installed read-me Þle.

Technical Support

If you have some problem using MDT that canÕt be solved by reading the manual, call technical support at (888) 332-2636, or (408) 399-0008 Monday through Friday between 9 AM to 5 PM PaciÞc Standard Time.

Also, you might Þnd what you want at our web page:

www.antaresTech.com

You can also e-mail:

techsupport@antaresTech.com

MDT UserÕs Manual

Getting Started

MDT UserÕs Manual

CHAPTER 2

Introducing MDT

MDT is a breakthrough among with dynamics processors. It puts your hands on the dials and levers of the DSP process itself, letting you shape the results in ways never available before. Access to this new level of ßexibility and control is achieved by shifting the way you think about how compression and expansion work. This chapter introduces MDTÕs operating paradigm and gives the information needed to use it effectively.

Understanding Compression

Next to reverb, compression is probably the most important signal process used in todayÕs studios. Simply put, compression reduces the of a signal. That is, it reduces the difference in loudness between the loudest and quietest parts of a piece of music. Another way to think about this is that the compressor is acting as an automatic fader which fades down when the music gets loud and fades back up when the music gets soft.

dynamic range

Why reduce the dynamic range? Consider mixing a vocal into a pop music bed. Typically, pop music has a relatively consistent level of loudness. If an uncompressed vocal track is added to a typical pop mix, certain loudly sung words or syllables would be very obtrusive, while quieter phrases would be buried underneath the instrumental texture. This is because the difference between the loudest and softest sounds in the vocal, its dynamic range, is very large. This same problem occurs for any instrument which had a dynamic range larger than the music bed into which it is being mixed.

By using a compressor to decrease the dynamic range of the vocal, the softer sounds are increased in loudness and the loudest sounds are reduced in loudness, tending to even out the overall level of the track. This makes the

MDT UserÕs Manual

Introducing MDT

vocal track sound generally louder and more distinct, and therefore, easier to hear in the mix.

Ratio And Threshold

How is compression measured? What is a little compression and what is a lot of compression? The concept called how much the dynamic range is compressed. Look at the illustration below.

compression ratio is

the measure of

1 to 1 r atio

2 to 1 r atio

THRESHOLD

OUTPUT LEVEL

Louder

I/O Curve

Louder

INPUT LEVEL

4 to 1 r atio 8 to 1 r atio

∞ to 1 ratio

This graph represents the relationship between the input level of the signal and the output level of the signal after compression. Notice that the curve has a breakpoint called a

threshold

. All standard compressors use a threshold. Signals that are louder than the threshold are processed (reduced in level) while those softer than the threshold are unchanged.

As the input signal exceeds the threshold,

gain reduction

(reduction in loudness) is applied. The amount of gain reduction that is applied depends on the compression ratio. The higher the compression ratio, the more gain reduction is applied to the signal.

The graph shows the relationship between compression ratio and gain reduction. Examine the 2 to 1 ratio curve. For signals above the threshold,

MDT UserÕs Manual

Understanding Compression

this curve transforms a range of loudness 2 units large into a range of loudness one unit large. Examine the ∞ to 1 curve. This curve transforms all sounds above the threshold to the same loudness. Dynamics processors which have this sort of curve are called limiters.

MDT As A Compressor

The graph described above appears in MDTÕs user interface. The following illustration is a screen shot of MDTÕs In/Out Grid.

THRESHOLD

4 to1 Ratio

I/O Curve

Like the Þrst graph, this is a graph of the Input Level versus the Output Level. The curve on the graph has a threshold and the curve segment above the threshold has a 4 to 1 compression ratio.

The gray bar at the bottom of the graph is an input level meter. It shows how loud the input signal is so that you can see where on the curve it falls. In the illustration below, the input level is at -18 dB. The threshold is at

MDT UserÕs Manual

Input Level

Introducing MDT

Output Level: -39 dB

-48 dB. The input is above the threshold so it is getting a gain reduction of

-21 dB. This puts the output at -39 dB.

Gain Reduction = 21 dB 4 to 1 Ratio

THRESHOLD = -48 dB

MDT UserÕs Manual

Input Level: -18 dB

The In/Out Grid

In conventional dynamics processors, there are knobs or sliders that control the threshold and ratio parameters. MDT uses a graphic interface called the In/Out Grid for these adjustments. The In/Out Grid provides visual feedback of the effect the tool is having on the sound. The complexity of the processorÕs conÞguration is easily controlled using multiple thresholds and their associated compression ratios.

The details of how to use MDTÕs graphic interface are explained in Lesson 1 of the MDT Tutorial.

MDTÕs I/O Curve can be arranged to create many different kinds of dynamic processing devices in addition to compressors. Many esoteric and expensive outboard dynamics processors can also be emulated. The Setting menu contains many settings which you will Þnd useful in creating ÒsweetÓ sounding digital expanders, spectral enhancers, companders, and other tools useful in mastering, tracking, and sound design. The examples below

Understanding Compression

explain some of the conÞgurations that are possible using MDTÕs unique graphic interface.

ÒSoft KneeÓ Compressor

Ratio = 4 to 1

Ratio = 3 to 1 Ratio = 2 to 1

Ratio = 1 to 1

ÒSoft kneeÓ compressors sound less obvious than regular Òhard kneeÓ compressors because the compression ratio near the threshold changes gradually. In the example above, as the signal gets louder than the threshold, it is Þrst compressed at 2 to1. As it gets louder still, the ratio goes to 3 to1, until, Þnally, it reaches its maximum ratio of 4 to 1. This setting sounds less ÒsquashedÓ than a plain 4 to 1 hard knee compressor because only the peaks in the signal get the full 4 to 1 compression.

The Òsoftest kneeÓ dynamics processors available are the tube-type compressors, especially the vintage variety. The following example shows how MDT can be conÞgured to emulate a tube compander.

MDT UserÕs Manual 17

Introducing MDT

ÒTubeÓ Compander

Compression Ratios

3 to 1

2.2 to 1

1.5 to 1

Expansion Ratios

1 to 1.5

1 to 2.2

1 to 3.0

1 to 4.0

1 to 1

The curve shown above has no clear threshold point where the signal starts to get processed. Instead, the compression or expansion ratios change gradually. It is called a compander because it both compresses and expands the dynamic range, depending on the level of the input. The top half of the curve compresses the dynamic range. The bottom half of the curve expands the dynamic range.

The sonic effect of processing through this kind of setting is very natural. Only the peaks of the sound get compressed heavily, while most of the signal passes through at a 1 to 1 ratio. This assumes that the average input level is around -40 dB. (See ÒThe Input Offset ArrowsÓ on page 27 for an explanation of how to ÒplaceÓ an input on the curve without actually changing its level.)

18 MDT UserÕs Manual

Sounds quieter than -48 dB get expanded downward, that is, they are faded down as they get softer. Because the curve increases in slope gradually, this subtle gating effect sounds very natural. It is useful for eliminating noise and maintaining a sense of wide dynamic range while still compressing the hot peaks in the signal.

Understanding Compression

Attack And Release Times

The attack time of a compressor is simply how long it takes for the compressor to react once the input level has met or exceeded the threshold level. With a fast attack time, the signal is brought under control almost immediately, whereas a slower attack time will allow the start of a transient or a percussive sound to pass through uncompressed before the processor has time to react. Creating a deliberate overshoot by setting an attack time of several milliseconds is an effective way to emphasize the percussive nature of instruments. The illustration below shows the effect of changing the attack time.

Uncompressed Input CompressedCompressed

1 mSec attack 10 mSec attack

The release time of a compressor is the time it takes for the gain to return to normal after the input level drops below the threshold. Setting too quick a release time can cause a pumping effect in the output. If the release time is too long, the compressor will not accurately track level changes in the input. The illustration below shows the effect of changing the release time.

Uncompressed Input

Compressed

1 mSec release

Compressed

50 mSec release

MDT UserÕs Manual 19

Introducing MDT

MDT In The TDM Environment

The TDM software environment is supported by hardware from Digidesign called the DSP Farm. Each DSP Farm card contains DSP chips on which MDT and other DSP plug-ins run. The TDM system requires that one chip on the DSP Farm be used for the Mixer plug-in which comes with ProTools. Assigning a large number of ProTools voices will sometimes require the use of two DSP chips on the DSP Farm.

MDT processes two audio channels per DSP chip. The table below shows how many DSP chips are used as more MDT channels are allocated.

Number of MDTs used Number of DSP chips allocated

2 mono to mono MDTs 1 1 stereo to stereo MDT 1 1 mono to mono plus 1 stereo to stereo MDT 2

NOTE: Sometimes TDM will post a warning dialog saying that there are an insufÞcient number of DSP chips available when you have added a normally legal number of MDTs. This is because of the order in which TDM allocates the DSP chips as you add more inserts. If this occurs, de-assign a MDT or two and then re-assign them. This allows TDM to sort out its DSP allocation, allowing the greatest use of the available DSP chips.

20 MDT UserÕs Manual

CHAPTER 3 MDT Tutorial

ÒI donÕt want to know how it works Ð

I want to know how to work it!Ó

Ð Keith Emerson

This chapter is a step-by-step explanation of how to use MDT. MDT is a breakthrough in technology and is therefore unique. If you follow these lessons one step at a time, you will master MDT and fully beneÞt from its capabilities.

The whole tutorial takes about 90 minutes to complete.

Lesson 1: MDT Basics

In/Out Grid

I/O Curve

Peak Level Indicator

Input Offset Arrows

Input Offset Display

Input/Output Display

This lesson presents the elements of MDTÕs user interface.

MDT UserÕs Manual 21

MDT Tutorial

About DSP Plug-ins

DSP Plug-ins are software programs that run inside ProTools, and other programs to add functionality and provide a variety of DSP tools. All TDM compatible plug-ins have a few basic features in common. This section describes those features.

1. Start ProTools and open the session named ÒMDT TutorialÓ.

2. Select ÒShow Inserts ViewÓ from the Display Menu.

3. Click on the MDT insert in the track labeled ÒAux 1Ó.

4. Choose Reset Settings from MDTÕs Setting menu.

5. In the Transport Window, click on the locator point labeled ÒShort VoiceÓ.

The Peak Level Indicator

1. Start playback with looping.

A Peak Level Indicator appears at the bottom of the In/Out Grid of MDT. It displays the current input level that MDT uses to make gain adjustments.

22 MDT UserÕs Manual

As the soundÞle plays, notice the dynamic range that the Peak Level Indicator covers.

MDT uses look-ahead peak averaging to determine the loudness of a sound. Look-ahead peak averaging means MDT scans the data about to be processed for upcoming peaks while calculating the average peak level of the data itÕs currently working on. It uses both numbers to derive the Þnal input level. MDT can scan up to 1024 samples ahead, depending on the DSP card being used.

2. Use the mouse to press on the right arrow of the Release slider. Increase the

release time to 4,999 mS (milliseconds).

Notice that, as the release time increases, the Peak Level IndicatorÕs movement slows down and the displayed signal level gets higher on the IN scale. This is because, as the release time increases, it takes longer for hot peaks to be averaged out of the level calculation. The actual signal

Press here to increase the Release time

Upper T erminator

Lesson 1: MDT Basics

may be ßuctuating wildly, but the displayed level will always be the average value of the peaks inside the time window determined by the Attack and Release settings.

3. Drag the Release slider to the far left position. Notice the change in the Peak Level Indicator.

With a release time of 0 milliseconds, the Peak Level Indicator more closely reßects the actual instantaneous sound level.

4. Stop playback.

5. Reset MDT by choosing Reset Settings from the Setting menu.

The I/O Curve

MDT uses a unique graphic interface to describe the relationship between Input and Output levels. This relationship is called the transfer characteristic or, in MDT parlance, the I/O Curve. This section demonstrates the manipulation of the I/O Curve.

Threshold

I/O Curve

In/Out Grid

Lower Terminator

In/Out Display

NOTE: Points on the I/O Curve or the In/Out Grid will always be written as a pair of negative numbers, e. g. -60:-60. The Þrst number is the location

MDT UserÕs Manual 23

MDT Tutorial

of the point on the In coordinate of the In/Out Grid. The second is equal to its Out value on the Grid.

1. Move your mouse cursor into the In/Out Grid.

The cursor changes into the cross cursor shape.

2. Click and drag the mouse inside the Grid.

A threshold appears in the I/O Curve. As you move the threshold around the Grid, the I/O Curve Òrubber bandsÓ to follow the movements of the cursor. Notice that the threshold location is displayed in the In/Out Display. Also notice that the In/Out Display shows the angle of the two moving line segments expressed as the ratio of the Input to the Output.

3. Release the mouse.

The threshold remains at the release point. It is now highlighted as shown in the illustration above.

4. Move the threshold to In/Out coordinates -60:-60 by placing the cursor over the threshold and dragging it to the new location.

24 MDT UserÕs Manual

5. Place the cursor over the lower terminator (the small square object in the lower left corner of the In/Out Grid) and drag it to the right to -60.5:-96.

Notice that the lower terminator is ÒgluedÓ to the In axis. It will always have an Out value of -96 dB. The In/Out Display shows the ratio of the moving curve segment. As you drag the lower terminator to the right, notice that it cannot go past the threshold at -60:-60. This is to prevent the I/O Curve from having more than one output value for any given input value.

6. Drag the upper terminator (in the upper right corner of the In/Out Grid) to 0:-48.

The upper terminator is glued to the Out axis. It will always have an In value of 0dB. During the drag, the In/Out Display shows the ratio of the moving curve segment.

7. Add a second threshold by clicking the cursor at -24:-24.

While positioning this threshold, notice that the In/Out Display is displaying the positive going curve on the left as an N to 1 ratio, and the negative going curve on the right as a -N to 1 ratio. It is possible to use MDT to create inverse gain functions.

Threshold at -24:-24

Upper terminator at 0:-48

Threshold at -60:-60

Lower terminator at -60.5:-96

Lesson 1: MDT Basics

At this point in the exercise, MDT should look like this:

8. Delete the thresholds by pressing <option> and clicking on the thresholds.

The thresholds disappear and the curve snaps to its new position automatically.

9. Reset MDT by choosing Reset Settings from the Setting: menu.

The In/Out Grid

MDT works by detecting the level of the input signal, looking for the point on the I/O Curve with that input value, and then adjusting the gain so that the output level equals that of the I/O Curve at that point.

All the possible points where the I/O Curve can exist are represented by the In/Out Grid. It is divided by a diagonal line that represents the points on the Grid that have input levels equal to output levels (e.g. -48:-48). Placing the I/O Curve on this diagonal will cause MDT to output the signal at the same level as it was input.

The points on the Grid which have output levels lower than their input levels (e.g. -48:-72) are located below the diagonal. Placing the I/O Curve below the diagonal will cause MDT to output the signal at a lower level than it was input (gain reduction).

MDT UserÕs Manual 25

MDT Tutorial

-72:-48

-48:-48

-48:-72

Points on the Grid which have output levels higher than their input levels (e.g. -72:-48) are located above the diagonal. Placing the I/O Curve above the diagonal will cause MDT to output the signal at a higher level than it was input (gain ampliÞcation).

The following section demonstrates the relationship between I/O Curve position and gain.

26 MDT UserÕs Manual

1. Choose 1:1, -12 dB gain from the Settings menu.

2. Start playback with looping.

The voice is heard 12 dB lower in volume because the I/O Curve shifts every point on the In axis -12dB on the Out axis.

3. Adjust the Gain slider to read 12 dB.

4. Click the Bypass button on and off to verify the level match.

The processed level is now precisely the same as the original level because of the additional gain supplied by the Gain slider. The gain factor set into the Gain slider is applied after the signal is processed by the I/O Curve and is the last stage of control in MDT.

5. Choose 1:1, -24 dB gain from the Settings menu.

The voice is heard 12 dB lower in volume because the I/O Curve has shifted everything an additional -12 dB lower on the Out axis.

6. Adjust the Gain slider to read -12 dB.

Lesson 1: MDT Basics

7. Choose 1:1, +12 dB gain from the Settings menu.

The voice is now heard at the original volume level. The I/O Curve is amplifying it by 12 dB and the Gain slider is reducing the gain by -12 dB. Use the Bypass button to verify this.

8. Stop playback.

9. Choose Reset Settings from the Settings menu.

The Input Offset Arrows

Input Offset is another unique feature of MDT. The Input Offset Arrows (see illustration) allow you to change the relationship of the input signal to the I/O Curve without actually changing the signal level of the input data.

Input Offset Arrows

In a single band conÞguration, the placement of the thresholds can be tweaked using the Input Offset without disturbing the I/O Curve. In multiband conÞgurations, spectral bands can be independently adjusted. By adjusting the different bands to the same level, coloration is reduced. Adjusting the different bands to completely separate sections of the I/O Curve allows independent compression ratios and levels for each band. These multiband cases will be demonstrated later.

1. Choose Input Offset Test from the Settings menu.

Input Offset Display

MDT UserÕs Manual 27

MDT Tutorial

2. Start playback with looping.

3. Press and hold down the downward Input Offset Arrow.

As the Peak Level Indicator moves to the left, notice that the loudness of the playback remains the same. This is because the input data is not being changed. Only its relationship to the I/O Curve is being changed.

When the Peak Level Indicator moves through the region between -36 dB and -60 dB on the Input scale, notice that the loudness of the sound decreases by 36 dB. This is because the I/O Curve is set for a -36 dB gain reduction in that region. As the Peak Level Indicator moves below -60 dB, the output goes back to normal because the I/O Curve is back at unity gain (0 dB gain).

The Input Offset Arrows always increment in 1 dB steps. Press <option> then press on the arrows slows the rate of change.

4. Press on the upward Input Offset Arrow until the reading returns to 0.

The value displayed in the Input Offset Display (see illustration) is the difference in dB between the actual input level and the displayed level.

5. Stop playback.

28 MDT UserÕs Manual

6. Choose Reset Settings from the Settings menu.

The Setting Menu

MDT has a Setting menu which allows you to store your most used MDT set-ups and instantly recall them. The Setting menu allows an unlimited number of ÒsnapshotsÓ of MDTÕs settings to be saved. This data is saved in the ÒMDT PreferencesÓ Þle in the SystemÕs ÒPreferencesÓ folder. In this section you will learn how to save, recall, and delete settings from the Setting menu.

1. Put four thresholds on the I/O Grid at In:Out = -12:-48, -24:-12, -36:-48, and -48:-12.

2. Choose 5 band AP from the Filter Mode menu.

3. Increase the Attack time to 50 mS.

4. Increase the Release time to 4,999 mS.

5. Decrease Gain to -24 dB.

6. Decrease the Low Band Input Offset to -15.

At this point MDT should look like this:

To save these settings,

Lesson 1: MDT Basics

1. Choose Save Settings AsÉ from the Setting menu.

A dialog box appears requesting a setting name.

2. Type Test in the text box and click on Save.

The settings are now saved under the name ÒTestÓ. These settings appear at the bottom of the Setting menu.

3. Choose Reset Settings from the Setting menu to revert to the default values.

To recall the setting;

1. Choose Test from the Setting menu.

The settings are recalled as you saved them.

To delete the setting;

1. Choose Delete SettingsÉ from the Setting menu.

A dialog appears with the list of the settings in the menu.

2. Scroll down to Test and select it by clicking on it.

3. Click on the Delete button.

MDT UserÕs Manual 29

MDT Tutorial

The setting is deleted from the menu. You may select multiple settings for deletion by shift-clicking or click dragging over the items to be deleted. To make a non-contiguous selection, press <command> and click on the items to select them. Note that the settings themselves remain on MDT until you move them yourself or choose another setting.

Lesson 2: Single Band Applications

The following section demonstrates how to conÞgure MDT as a single band compressor, limiter, gate, expander, Òsoft kneeÓ compressor/gate, and ÒtubeÓ compander.

Compressor

1. Select the ÒFetes 1Ó soundÞle for playback.

2. Click on the MDT insert in the track labeled ÒAux 1Ó.

30 MDT UserÕs Manual

3. Choose Reset Settings from the Setting menu.

4. Start playback with looping.

The selection is an excerpt from Fetes (rhymes with ÒpetÓ), the second of DebussyÕs Nocturnes for orchestra. Notice the relative loudness of the brass notes compared to the quiet strings that follow. The Peak Level Indicator shows an approximate dynamic range of -24 dB.

5. Choose 3:1, -48 dB threshold from the Settings menu.

Notice the shape of the I/O Curve. Sounds that have input levels lower than -48 dB are in a 1 to 1 relationship with the output. Above -48 dB, the signal will get a different gain reduction depending on its input level.

For example, a sound input at -12 dB will get a -24 dB gain reduction and be output at -36 dB. A sound at -24 dB input will only get a -16 dB gain reduction and be output at -40 dB, and so on. A piece of music with a dynamic range from -12 dB to -36 dB (a 24 dB dynamic range) would be output from -36 dB to -44 dB (an 8 dB dynamic range). Shrinking 24 dB down to 8 dB is a 3 to 1 compression ratio.

Lesson 2: Single Band Applications

-24 dB gain

-16 dB gain

The Gain slider is set at 18 dB to compensate for the gain reduction of the compressor. The loudest sounds will come out at approximately the same level as before compression.

Notice how the quiet string passage is now louder than before. The brass remains at its previous level.

6. Use the Bypass button to compare the original with the compressed signal. Deactivate Bypass when youÕre done.

7. Change the compression ratio to 4 to 1 by dragging the upper terminator down until the Left Ratio Þeld in the I/O Display equals 4:1.

The compression ratio approaches ∞ to 1 as the I/O Curve approaches the horizontal. At a ratio of ∞ to 1, all sounds above the threshold would

be output at the same level.

8. Stop playback.

Attack and Release Times

The time it takes for MDT to react to an incoming peak is controlled by the Attack Time. The Release Time determines how fast the input level will return to its quiescent state after the peak comes through. The following section is a demonstration of the effect that Attack and Release times have on the sound.

MDT UserÕs Manual 31

MDT Tutorial

A four unit change in the input gives a one unit change on the output.

MDT should now be adjusted to a 4 to 1 compression ratio from the last section. If it isnÕt, please do this now.

1. Select the ÒpluckÓ soundÞle for playback.

2. Reduce the Gain setting to 14.

3. Start playback with looping.

4. Use the Bypass button to compare the original with the compressed signal. Deactivate Bypass when youÕre done.

The region, ÒPluckÓ, is a loud violin section pizzicato with a reverb tail. Notice how the compression exaggerates the reverb and the noise in the sample. Notice the ÒshapeÓ of the reverb tail and its decay time. Also notice the body of the attack portion of the sample.

5. Reduce the Attack time to 0 mS.

32 MDT UserÕs Manual

The initial attack is now compressed. MDT reacts immediately to change the gain so that the attack is output at a much lower level.

6. Press on the right arrow of the Attack slider. Notice the change in the body of the sound as the Attack time increases.

At 50 mS, the attack is much louder than the sustained portion of the ÒPluckÓ. Changing the Attack time lets you tailor the aggressiveness of the attack to your needs.

7. Return the Attack setting to 20 mS.

Lesson 2: Single Band Applications

8. Increase the Release setting to about 5,000 mS.

Notice how the reverb tail sounds almost exactly like the uncompressed version. This is because the Release time is much longer than the reverb time. The shape of the reverb tail is not effected because the detected input level (as shown by the Peak Level Indicator) decays very slowly when the Release time is this long.

This slow release time has an additional effect. Since the peak input level is high, the gain reduction of the output signal is also high, causing it to play back more softly than before. The Gain slider can be adjusted to compensate for this effect.

9. Decrease the Release time to about 300 mS.

At this setting, the rate of change in output gain is approximately equal to the reverb decay rate. The result sounds like a smooth decay with the reverb compressed.

10. Stop playback.

MDT UserÕs Manual 33

MDT Tutorial

Expander/Gate

MDT can be used as an expander/gate to eliminate noise and for creating gated effects. This section demonstrates how to use the I/O Curve to conÞgure a downward expanding gate.

1. Choose 1:1, -36 dB gate from the Settings menu.

34 MDT UserÕs Manual

1. Start playback with looping.

As the reverb decays below the -36 dB threshold, the output gain changes to -60 dB, gating the sound off.

2. Press <option> and then the downward Input Offset Arrow until the display reads -15.

The reverb tail is now gated off sooner because the input level reaches the -36 dB threshold sooner. The Input Offset Adjust Arrows can be used in conjunction with the Release time slider to get exactly the gate time you wish.

1 to 2.0 expansion ratio

Lesson 2: Single Band Applications

3. Move the lower terminator to the left until the value displayed in the I/O Display equals 1:2.0.

The reverb now decays evenly because the output gain tapers gradually below the -36 dB threshold.

4. Stop playback.

Example 2: Compressor with Noise Gate

1. Select the ÒShort VoiceÓ soundÞle for playback.

2. Choose 3:1, -48 dB threshold from MDTÕs Settings menu.

3. Start playback with looping.

Notice that the region has a high noise ßoor. The noise level is just below the -48 dB threshold.

4. Drag the lower terminator to the right as far as it will go.

You will hear that the noise is gated out for the most part. There is still a small noise just after the words ÒÉSound Designer IIÉ(noise)Ó.

5. Decrease the Gain setting to 9 dB.

6. Press <option> and then the downward Input Offset Arrow until the display reads -15.

MDT UserÕs Manual 35

MDT Tutorial

The noise is virtually eliminated because the input signal has been shifted down in relationship to the gating threshold. The noise now gates off immediately.

7. Stop playback.

ÒTubeÓ Compander

Many complex signals like full mixes and vocals require a high degree of dynamic control, but suffer from the effects of heavy compression or limiting. The use of a Òsoft kneeÓ compressor or Òtube-likeÓ compander can make the effects of strong compression less obvious. A Òsoft kneeÓ compressor is characterized by having a gradual change in compression ratio at its threshold. A ÒtubeÓ compander has a continuously varying compression ratio over the range of the input.

Example 1: ÒSoft KneeÓ comp/gate

1. Choose Òsoft kneeÓ 4:1 -36 dB from the Settings menu.

36 MDT UserÕs Manual

2. Start playback with looping.

Compare this sound with the previous example. The voice sounds less ÒsquashedÓ even though the compression ratio is higher because the change in ratio at the threshold is less abrupt.

3. Stop playback.

Lesson 2: Single Band Applications

Example 2: ÒtubeÓ comp/gate

1. Choose ÒtubeÓ comp/gate from the Settings menu.

2. Start playback with looping.

Contrast the sound of the voice with the previous two settings. The vocal sound is even more natural because, most of the time, it is sitting on an area of the I/O Curve which has relatively small compression/expansion ratios. Only the peaks or valleys of the signal are effected by the high ratio segments of the I/O Curve.

The reason ÒtubeÓ companders work so well for complex signals is because the compression/expansion ratio changes gradually from some central operating point Ð in this case, -36 dB, making the effects of compression less audible. Normal compressors maintain the same ratio over a wide dynamic range.

3. Stop playback.

MDT UserÕs Manual 37

MDT Tutorial

Example 3: Full mix

1. Select the ÒFetes 1Ó soundÞle for playback.

2. Select the Fetes 1 tube from the settings menu.

3. Start playback with looping.

38 MDT UserÕs Manual

The ratios of the downward expander part of the curve have been relaxed in this setting to accommodate the lower level and dynamic range of this excerpt. Compare the sound of this setting with the sound of the 3:1, -48 threshold setting that you used above.

4. Use the Bypass button to compare the original with the compressed signal. Deactivate Bypass when youÕre done.

5. Stop playback.

Lesson 3: Multiband Applications

In this lesson, you will learn how to use MDT in multiband mode. This capability of MDT makes it the most powerful and ßexible dynamics processing tool available.

Multiband Peak Level Indicators

In multiband mode, MDT divides the energy of the signal into three or Þve equally spaced bands. The peak level of each band is displayed by its own Peak Level Indicator at the bottom of the In/Out Grid.

1. Select the ÒShort VoiceÓ soundÞle for playback.

2. Select 3 band from the Filter Mode menu.

3. Start playback with looping.

The Peak Level Indicators display the level of each band. The three bands (High, Mid, Low) are shown in that order, the Low band being at the bottom of the In/Out Grid. Each band is 3.3 octaves wide and has its own Input Offset Arrows.

High Band

High Mid Band

Mid Band

Low Mid Band

Low Band

4. Select 5 band from the Filter Mode menu.

In 5 band mode, Þve Peak Level Indicators are shown - High, Hi-Mid, Mid, Low-Mid, and Low. Each band is 2 octaves wide.

MDT UserÕs Manual 39

MDT Tutorial

The Filter Modes

MDT uses digital Þlters to separate the energy of the input signal into multiple bands. These Þlters have particular characteristics which need to be understood to use MDT most effectively.

In the 3 Band mode and 5 Band mode, with the I/O curve along the diagonal line, MDT responds like an equalizer with gain levels set ßat. This means there are +/- 1dB variations in amplitude as a function of frequency.

3 Band AP and 5 Band AP works differently, so that the output is identically equal to the input, and the Þlters only become involved when the gain curve is not on the diagonal.

Why not use the AP mode all the time? The AP mode Þlters have a limited gain reduction range of -12 dB. This means that the input signal can't be attenuated more than 12 dB. In cases where more gain reduction is needed, the non-AP versions will give the best result.

Placing the I/O Curve in the shaded parts of the Grid will cause unpredictable changes in the tonal balance when using AP mode ﬁlters.

40 MDT UserÕs Manual

Multiband Compressor

There are many times when it is necessary to compress a complete mix. Often, especially when compressing at a high ratio, ÒpumpingÓ can occur. This is when one sound or group of sounds in the mix is modulating the

Lesson 3: Multiband Applications

loudness of the other sounds. The following example demonstrates the use of a multiband compressor to alleviate the pumping problem.

1. Select the ÒBass SoloÓ soundÞle for playback.

2. Choose Pumping 1 band in the Setting menu.

The compression ratio above the threshold is 10 to 1.

3. Start playback with looping.

Notice how the loudness of the cymbal and sustained pad is ÒpumpedÓ by the bass solo.

4. Choose Better 5 band in the Setting menu.

This setting is the same as before except for the use of multiband mode. Notice how the pumping effect is greatly reduced.

Extreme settings are used in the example so as to create pumping in the output for the purposes of illustration. In a real world application, with a more moderate compression ratio and release time, the multiband compressor would provide even better results.

MDT UserÕs Manual 41

MDT Tutorial

Managing Tonal Balance In Multiband Mode

What is the Tonal Balance Problem?

You may have noticed in the previous exercises that the multiband Peak Level Indicators almost never have the same simultaneous level. This is because the energy distribution across the spectrum changes from moment to moment. Since all the bands are using the same I/O Curve, each band may receive a different gain depending on its current level and placement on the I/O Curve. The following example demonstrates this behavior.

1. Select the ÒShort VoiceÓ soundÞle for playback.

2. Choose 3:1, -48 dB threshold in the Setting menu.

3. Start playback with looping.

Listen for the tonal balance of the voice.

4. Choose 3 Band in the Filter Mode menu.

42 MDT UserÕs Manual

-15 dB

-8 dB

Notice how the tonal balance is brighter. The highs are accentuated because the average level of the High band is about 5 dB lower than the other bands. This means that it is getting less gain reduction than the other bands and is therefore ÒhotterÓ in relation to them.

5. Stop playback.

Offsetting the inputs so that they are about equal insures that all the bands receive the same gain.

Lesson 3: Multiband Applications

How To Achieve Tonal Balance

It is often desirable to preserve the soundÞleÕs original tonal balance while beneÞting from using multiband mode. The key element in preserving tonal balance is having each band get the same amount of gain at the same time. You can do this by offsetting the input level of the ÒhotterÓ bands to equal the lowest level band. The following exercise demonstrates two different ways to achieve this.

1. Start playback with looping.

2. Press and hold the ÒFlatÓ button for about 2 seconds.

The Input Offset values for each band are automatically adjusted so that they have equal amounts of gain reduction over the period of time the Flat button is held down. That is, the Input Offset values are adjusted so that the bands receive, on the average, equal amounts of gain reduction as measured over the period the button is held down. This technique is applicable when the natural tonal coloration of the sound does not vary, as is the case with a single speakerÕs voice.

3. Choose Full Band in the Filter Mode menu.

Notice how the 1 band tonal balance closely matches the tonal balance of the adjusted 3 band sound.

4. Click on the ÒResetÓ button to zero the Input Offset values.

5. Click on the ÒVariableÓ button.

MDT UserÕs Manual 43

MDT Tutorial

The Input Offset values now change continuously, in an ongoing effort to achieve equal amounts of gain reduction. The amount of gain reduction is measured over a period of time equal to three times the compressor release time. In this way, the separate bands can respond individually to what is occurring in the sound, but at the same time, they are being drawn towards one-another to preserve the original tone color.

Using the ÒVariableÓ button will preserve the original tone color of sounds having variable tone color. The ÒFetesÓ and the ÒBass SoloÓ are good examples of this.

6. Stop playback.

IMPORTANT:

The ÒVariableÓ button requires CPU processing to work. MDT does this processing when it is given control of the CPU to update meters. MDT is not given the CPU when the plugin is not visible. Hence, the ÒVariableÓ button will not work when the plugin is not visible. In order to achieve the effect of the ÒVariableÓ button when the plugin is not visible, you must record the resulting input offset level changes using automation in ProTools 4.

44 MDT UserÕs Manual

Lesson 3: Multiband Applications

MDT As A Spectral Enhancer

The tonal ßexibility demonstrated above can be used to modify the existing tonal balance dynamically. De-essers, spectral enhancers, and dynamic EQs all modify the tonal balance dynamically. This example below shows how to use MDT to perform these functions.

De-esser

1. Select the ÒShort VoiceÓ soundÞle for playback.

2. Choose 6:1 de-esser in the Setting menu.

The compression ratio above the threshold is 6 to 1. Notice how the I/O Curve straddles the diagonal. Sounds above the threshold and to the left of the diagonal get ampliÞed. Sounds to the right of the diagonal receive gain reduction.

3. Start playback with looping.

Notice how the High band is effected by compression and the other bands are offset so they get no compression.

4. Use the Bypass button to compare the original with the compressed signal.

MDT UserÕs Manual 45

MDT Tutorial

5. Press the High band's downward Input Offset Arrow until the display reads -14.

The High band peaks will occur at approximately the 0 dB gain line (the diagonal). This setting should sound very similar in tonal balance to the original. Any high frequency peaks will be compressed at a 6 to 1 ratio.

Spectral Enhancer

1. Press the High band's downward Input Offset Arrow until the display reads -20.

46 MDT UserÕs Manual

The High band peaks are now occurring in the area of the I/O Curve to the left of the diagonal. The sound is brighter because the highs are getting ampliÞed while still being compressed at a 6 to 1 ratio.

2. Experiment with changing the tonal balance by moving the other bands into the compression segment of the I/O Curve.

3. Use the Bypass button to compare the original with the enhanced signal.

4. Stop playback.

With the current setting of the I/O Curve, the louder a band gets, the more gain reduction it receives. The next example shows how to conÞgure MDT as a dynamic EQ.

1 to 1.5 expansion ratio

Lesson 3: Multiband Applications

Dynamic EQ

A dynamic EQ is a device that changes the amount of equalization it applies as a function of input level or some other changing parameter of the signal. MDT can be conÞgured as a dynamic EQ as shown below.

1. Select the ÒFetes 1Ó soundÞle for playback.

2. Choose High Freq. Expander in the Setting menu.

The expansion ratio above the threshold is 1 to 1.5.

3. Start playback with looping.

Notice how the High and Hi Mid bands are effected by expansion and the other bands are offset so they get no expansion. The louder the input signal, the greater the ampliÞcation of the highs.

4. Use the Bypass button to compare the original with the enhanced signal.

5. Experiment with changing the brightness of the sound by changing the offset of the High and Hi Mid bands.

The effect can range from subtle to gross depending on the ratio of the I/O Curve and the position of the band on the curve.

6. Stop playback.

MDT UserÕs Manual 47

MDT Tutorial

Lesson 4: Clip Sentry

This lesson will step you through how to use Clip Sentry.

Because MDT simulates the smooth sound of analog compressors, it is easy to create data that exceeds to +1,-1 digital range. This is because of the behavior of the Attack Time slider, which allows you to control the rate of gain reduction due to a sudden increase in sound level. As in the analog world, even a fast attack time will let through a faster transient. Since most users jack-up the output gain to compensate for compression, these fast transients almost always result in clipped data.

Clip Sentry is a high speed digital limiter designed to prevent clipping by reducing gain only when clipping is about it occur.

1. Select the ÒShort VoiceÓ soundÞle for playback.

2. Choose ÒReset SettingsÓ from the settings menu.

3. Start playback with looping.

48 MDT UserÕs Manual

Notice how the gain reduction meter does not move. This is because the I/O Curve is along the diagonal line. Hence no gain reduction is prescribed.

4. Increase the ÒGain (dB)Ó until the clipping begins to occur.

You can tell when clipping occurs because the clip light above the gain reduction meter ßashes red.

5. Click the ÒClip SentryÓ button in.

You will now see that gain reduction occurs when clipping used to occur. Also, notice that additional processing delay has been inserted into the signal path.

6. Reduce the amount of delay to 5 mSec by changing the Clip Sentry Buf Len.

The Clip Sentry Buf Len causes less delay to occur for processing but it also causes the gain reduction to occur more quickly. Depending on the source material, shortening the delay will eventually cause objectionable distortion.

7. Gradually decrease the Clip Sentry Release time.

Lesson 5: Using Automation

This causes the gain reduction to recover more quickly. Be careful, though. If the gain reduction recovers too quickly, data in the Clip Sentry buffer may cause superÞcial clipping to occur. A release time of 100 rarely produces clipping.

8. Stop playback.

If a large gain reduction occurs, a very short release will be less audible, but may sound unnatural. A longer release time will be more audible. The Release (mS) slider controls how rapidly the gain is allowed to change. Hence, you have the Release Slider set to 1000 and rapidly increase the Gain Slider, you will Þnd the actual output gain shows by the gain reduction meter will increase slowly.

With Clip Sentry, if youÕre doing Rock-n-Roll, you can push it to the wall. If you have big Þnal gain, short Buf Len (mS) and short Release (mS), you can make a REALLY loud piece. Just listen carefully for distortion: You will be creating more distortion from the fast gain change of a short Buf Len (mS) than the occasional slight clip from the short Release (mS).

Lesson 5: Using Automation

ProTools version 4.0 introduces Automation for plugin controls.

All buttons and sliders (except for the ÒVariableÓ, ÒFlatÓ and ÒResetÓ buttons) have been automated when used with ProTools 4.0. Note that the ÒVariableÓ, ÒFlatÓ and ÒResetÓ buttons control the Input Offset Levels, which are automated. Hence, you can automate the effects of the ÒVariableÓ, ÒFlatÓ and ÒResetÓ buttons by using them when the input offset levels' automation is recorded.

The MDT Settings menu is also automated. Care must be taken, however, not to automate ÒSave Setting As...Ó or ÒDelete Setting...Ó because these dialogs will be posted when automation plays back. Moving points in the I/O Graph cannot be automated, although changing sets of points can be recalled with the Settings Menu automation.

This lesson steps you through how to use automate the effects of the ÒVariableÓ button (a very important tool for preserving tone color).

MDT UserÕs Manual 49

MDT Tutorial

1. Select the ÒShort VoiceÓ soundÞle for playback.

2. Choose 3:1, -48 dB threshold in the Setting menu.

3. Select Ò5 BandÓ from the Filter Mode menu.

4. Enable the Input Offset arrows for automation.

In ProTools 4, click the ÒautomationÓ button in the plugin window and ÒAddÓ the controls ÒLevel4Ó, ÒLevel3Ó, ÒLevel2Ó, ÒLevel1Ó and ÒLevel0Ó. After clicking the ÒOKÓ button, the Input Offset Arrows will be hilited Green. Next change the trackÕs Òauto readÓ to Òauto touchÓ.

5. Click the ÒVariableÓ button in.

6. Start playback with NO looping.

Playback will end after ÒShort VoiceÓ plays through.

7. Click the ÒVariableÓ button out and change Òauto touchÓ to Òauto readÓ.

8. Start playback.

You will see that the Input Offset Arrow changes were recorded and that playback automation resulted from the ÒVariableÓ button having been pushed during recording.

50 MDT UserÕs Manual

9. Stop playback.

Lesson 5: Using Automation

New Possibilities

You have probably thought of numerous applications for MDT that have not been mentioned in the Tutorial. We hope that you have learned enough about whatÕs possible with MDT that you feel free to experiment and create ways to use it that are far beyond anything we expected.

Here is something to play with as a starting point that could produce unique results in a sound design application.

Inverted Gain Curves

In the region effected by the inversion, increasing input level decreases the output. Try out the Inverse Pluck setting with the ÒpluckÓ soundÞle.

MDT UserÕs Manual 51

MDT Tutorial

52 MDT UserÕs Manual

CHAPTER 4 MDT Reference

This chapter explains the detailed operation of every aspect of MDTÕs user interface. The items are organized in alphabetical order to make them easy to locate.

Attack Slider

The Attack slider controls the amount of time it takes for MDT to react to an incoming peak. The range of the control is from 0 milliseconds to 50 milliseconds. The current attack time is displayed in the window to the left of the slider.

Clicking on the arrows decrements/increments the attack time by one millisecond. Pressing on the arrows decrements/increments the attack time continuously. Press <option> to slow the speed at which the value increments. The thumb wheel can be dragged for making gross adjustments.

Automation

All buttons and sliders (except for the ÒVariableÓ, ÒFlatÓ and ÒResetÓ buttons) have been automated when used with ProTools 4.0. Note that the ÒVariableÓ, ÒFlatÓ and ÒResetÓ buttons control the input offset levels, which are automated. Hence, you can automate the effects of the ÒVariableÓ, ÒFlatÓ and ÒResetÓ buttons by using them when the input offset levels' automation is recorded.

MDT UserÕs Manual 53

MDT Reference

The Settings menu is also automated. Care must be taken, however, not to automate ÒSave Setting As...Ó or ÒDelete Setting...Ó because these dialogs will be posted when automation plays back. Moving points in the I/O Graph cannot be automated, although changing sets of points can be recalled with the Settings Menu automation.

Bypass Button

Clicking on the Bypass button bypasses the settings of MDT. This is useful for comparing the original soundÞle to the processed version being previewed. Clicking again will revert to the current settings.

Clip Sentry Button

54 MDT UserÕs Manual

Clip Sentry is a high speed digital limiter designed to prevent clipping by a reducing gain only when clipping is about it occur.

The indicator light to the right of the Clip Sentry button shows when the Clip Sentry is being activated.

Clip Sentry Buf Len (mS) slider

A very short length will introduce distortion by making rapid gain reductions. This distortion will be minimal if Clip Sentry does not reduce the gain too often or too much. A long length will introduce more delay in the processed data and even produce audible drop-outs before transients on some sounds.

Clip Sentry Release (mS) slider

If a large gain reduction occurs, a very short release will be less audible, but may sound unnatural. A short release also increases the chance that the gain will recover too quickly, causing a mild clipping of audio data that is already in the buffer. A release time of 100 rarely produces clipping. A longer release time will be more audible. The Release (mS) slider controls how rapidly the gain is allowed to change. Hence, you have the Release Slider set to 1000 and rapidly increase the Gain Slider, you will Þnd the actual output gain shows by the gain reduction meter will increase slowly.

Clipping Indicator

With MDÕs soft clipping, it is difÞcult to hear when clipping occurs. To Þx this, use the Clip Indicator above the Gain Reduction meter. The Clip Indicator is initially black. It brießy turns yellow whenever MDT output hits

MDT UserÕs Manual 55

MDT Reference

+1,-1 values. After the yellow subsides, it latches to red. You may reset it to black by clicking on it.

Control Surface Support

TDM pagetables have been implemented allowing MDT to be controlled by external control surfaces, including the JL Cooper CS-10, Peavey PC 1600, Digidesign ProControl and Mackie HUI.

Delay Window

The Delay Window shows the amount of time in seconds that MDT will delay a trackÕs sound output. This delay is introduced due to MDTÕs Òlook aheadÓ peak detection feature and processing delay. The amount of the delay introduced gets larger with the number of bands used. Tracks can be slipped to the left by the amount shown in the Delay Window to resynchronize their output with other non-processed tracks.

56 MDT UserÕs Manual

Filter Mode Menu

MDT uses digital Þlters to separate the energy of the input signal into multiple bands. The Filter Mode Menu contains the following choices:

¥ Full Band: No Þlters are used. The sound is processed in one band. The

frequency response of this mode is 0 Hz to the Nyquist, ±0.0 dB with no

passband ripple.

¥ 3 Band: The signal is divided into 3 equal bands, 3 octaves in width. The

frequency response of this mode is 0 Hz to the Nyquist, ±0.0 dB with ±0.7 dB passband ripple.

¥ 5 Band: The signal is divided into 5 equal bands, 2 octaves in width. The

frequency response of this mode is 0 Hz to the Nyquist, ±0.0 dB with ±0.3 dB passband ripple.

¥ 3 Band AP: The signal is divided into 3 equal bands with a special Þlter

design optimized for the ßattest pass band near unity gain. The fre-

quency response of this mode is 0 Hz to the Nyquist, ±0.0 dB with ±0.0 to

0.7 dB passband ripple.

¥ 5 Band AP: The signal is divided into 5 equal bands with a special Þlter

design optimized for the ßattest pass band near unity gain. The fre-

quency response of this mode is 0 Hz to the Nyquist, ±0.0 dB with ±0.0 to

0.3 dB passband ripple.

The AP (all pass) versions of the multiband Þlters are optimized for minimum coloration at gains around 0 dB. Because of hardware limitations, the AP mode Þlters have a limited gain reduction range of -12 dB. This means that the input signal can't be attenuated more than 12 dB without having its tonal balance seriously altered. In cases where more gain reduction is needed, the normal non-AP version of the Þlter will give the best result.

Placing the I/O Curve in the shaded parts of the Grid will cause unpredictable changes in the tonal balance when using AP mode ﬁlters.

MDT UserÕs Manual 57

MDT Reference

Flat Button

Pressing the Flat Button equalizes the apparent input level of the bands displayed in multiband modes. MDT adjusts the offset of each band to equal the apparent level of the quietest band. As long as you hold down the ÒFlatÓ button, the spectral band levels are averaged, and input offset level adjustments are continuously updated. Consequently, the average coloration over the period the ÒFlatÓ button is held down will be neutral.

Gain Slider

The Gain slider adjusts the loudness of the signal after processing. The range of the control is from -24 dB to +24 dB. The current gain is displayed in the window to the left of the slider.

58 MDT UserÕs Manual

Clicking on the arrows decrements/increments the gain by one deciBel. Pressing on the arrows decrements/increments the gain continuously. Press <option> to slow the speed at which the value increments. The thumb wheel can be dragged for making gross adjustments.

Input Offset Arrows

The Input Offset Arrows allow you to change the relationship of the input signal to the I/O Curve without actually changing the signal level of the input data. The placement of thresholds can be tweaked in this way. In multiband conÞgurations, spectral bands can be independently adjusted. By adjusting the different bands to the same input level, coloration is reduced. Adjusting the different bands to completely separate sections of the I/O Curve allows independent compression ratios and levels for each band. The range of adjustment is from 0 dB to -96 dB.

The Input Offset Arrows normally increment in 2 dB steps. Press <option> then click or press on the arrows to increment is 1 dB steps.

Input Offset Arrows

Input Offset Display

In/Out Display

The In/Out Display shows the position of the cursor when it is located inside the In/Out Grid. The units displayed are in dB below full scale. The In/Out Display shows the location of thresholds and terminators when they are being dragged.

When dragging a threshold, the In/Out Display also shows the compression or expansion ratios of the curve segments on either side of the threshold. Ratios expressed as N to 1 are compression ratios. Ratios expressed as 1 to N are expansion ratios. Ratios expressed as 1 to -N or -N to 1 are inverse gain curves which donÕt have equivalents in the analog world.

In/Out Grid

The In/Out Grid is the primary interface for controlling MDT.

MDT UserÕs Manual 59

MDT Reference

-72:-48

Click, or click-drag to position new points on the I/O Grid. To delete a point, place the cursor over the point (a special cursor is activated) and option-click the point.

-48:-48

-48:-72

60 MDT UserÕs Manual

To move a point, place the cursor over the point (a special cursor is activated) and click-drag it. The new setting takes effect while the mouse is moving (you hear the drag as you move the point). On slower machines, you may want to press and hold down <shift> while changing the I/O Curve. This will cause MDT change the curve setting only after the point drag is complete.

Release Slider

The Release slider adjusts the time it takes for MDT to return to its quiescent state after a peak comes through. The range of the control is from 0 milliseconds to 5,000 milliseconds. The current release time is displayed in the window to the left of the slider.

Clicking on the arrows changes the release time in small increments. Pressing on the arrows decrements/increments the release time continuously. Pressing <option> before clicking or pressing on the arrows decrements/ increments the release time in 1 millisecond steps. The thumb wheel can be dragged for making gross adjustments.

Reset Button

Clicking the Reset Button zeros the Input Offset values shown in the Input Offset Window.

Setting Menu

The Setting menu contains the list of settings that are stored in the MDT Preferences Þle in the System Extensions folder. Any number of settings can be saved in the Setting menu.

To save a setting;

1. Choose Save Settings AsÉ from the Settings menu.

A dialog box appears requesting a setting name.

2. Type the desired name in the text box and click on Save.

MDT UserÕs Manual 61

MDT Reference

The settings are now saved. These settings appear at the bottom of the Setting menu.

To recall a setting;

1. Choose it from the Setting menu.

The settings are recalled as you saved them.

To delete the setting;

1. Choose Delete SettingsÉ from the Setting menu.

A dialog appears with the list of the settings in the menu.

2. Scroll down to Test and select it by clicking on it.

3. Click on the Delete button.

62 MDT UserÕs Manual

TDM Settings and the Compare Button

The ProTools 4 TDM settings feature has been implemented. The TDM settings recall all control values (all buttons and sliders) as well as the I/O curve. Although recalling these settings is not automated as the MDT Settings menu has been, the TDM settings features do offer additional ßexibility in selecting Þle storage options.

The ProTools 4 ÒCompareÓ button has been implemented. This provides automatic comparison between the current TDM setting and the existing control values (including the I/O curve points). By pressing the ÒCompareÓ button, you can instantly exchange these settings, effectively doing an A/B comparison.

When the ProTools 4 TDM settings feature or the ÒCompareÓ button are used, the MDT Settings menu is restored to the saved status. However, the remaining control settings reßect other restored values rather than values from the MDT Setting menu item

Thresholds And Terminators

THRESHOLD

Upper T erminator

Lower Terminator

Up to 30 thresholds can be placed on the In/Out Grid to Òrubber bandÓ the I/O Curve. The rules for using thresholds are as follows.

To: Do This:

place a threshold on the curve, click in the In/Out Grid. display the location of a threshold click on the threshold move an existing threshold, click and drag it to the new location. delete a threshold, press <option> and click on the threshold.

The lower terminator is ÒgluedÓ to the In axis. It will always have an Out value of -96 dB. It can never exist to the right of a threshold, that is, have a higher input value than a threshold. This is to prevent the I/O Curve from having more than one output value for any given input value.

The upper terminator is glued to the Out axis. It will always have an In value of 0dB.

Variable Button

MDT is unbelievably smooth because it removes pumping by compressing spectral bands separately. However, the most problematic aspect of MDT (and all multiband compressors) is created by the multiband feature: When some spectral bands are hotter than others, they are compressed more, thereby coloring the sound.

MDT UserÕs Manual 63

MDT Reference

IMPORTANT:

Setting this button causes the input offset levels to be continuously adjusted so the band levels are, on the average, even with one-another. This causes the output sound to have no coloration. The speed of these adjustments is three times slower than the compressor release time. Hence, no matter what the release time setting is, using the ÒVariableÓ button will not interfere with the bands compressing independently from one-another. Once the ÒVariableÓ button is set, pressing any other level control (ÒFlatÓ, ÒResetÓ or the input offset arrows) pops it out.

64 MDT UserÕs Manual

CHAPTER 5 Theory of Operation

MDT has been designed to provide enormous power and ßexibility through the use of a simple user interface. However, since MDT is a new technology, some users may Þnd it interesting or helpful to have a deeper understanding of the conceptual elements of MDT's actual processing algorithms.

This chapter has been written to satisfy that need. The concepts behind MDT's processing algorithms are presented here in sufÞcient detail so that the behavior of MDT is precisely explained. To provide as much simplicity as possible, the various sections of this chapter describe the processing that occurs for monaural sound data. The last section of the chapter describes how MDT processing occurs for a stereo sound source.

The Gain Adjust Algorithm

The most basic computation in MDT is the Gain Adjust. In the various diagrams in this chapter, the Gain Adjust computation is represented by the symbol:

Gain Adjust

The purpose of the Gain Adjust computation is to perform the gain computation on one channel of data. This includes computing the signal level, scaling the level according to the user deÞned input level offset value,

MDT UserÕs Manual 65

The Gain Adjust Algorithm

and computing and applying the Þnal gain. The details of the Gain Adjust computation are given by the diagram:

input level offset

input

compute level

delay

input level

multiply

scaled input

level

output level

output level ÷ input level

output gain

output

multiply

The diagram above shows that as each sound sample is presented, a new input level is computed. The input level is a positive valued number between 0 (-96 dB) and 1 (0 dB). The input level is then multiplied by the user deÞned input level offset value to give the scaled input level. This value is presented to the user on the In/Out Grid as a horizontal bar. It is then used as the input setting on the I/O Curve to look-up the output level. The output level is divided by the input level to produce the output gain.

As an example of this processing, consider the case where the I/O Curve is a 45 degree 1:1 diagonal. In this case, the output level will always equal the scaled input level and the resulting output gain will always be unity. This means the sample output will be identically equal to the sample input.

Each incoming sound sample is also stored in a Þrst in/Þrst out (FIFO) buffer. To compute the output sound, samples are taken from the FIFO buffer. This is represented in the diagram above as delay. The amount of delay introduced by MDT is shown in the Delay Window.

For example, suppose the I/O Curve represents a compressor plus gain. Soft sound data would result in a high output gain. With no delay, if the sound were to become loud more quickly than the attack time, the high output gain would be applied to the loud sound resulting in output overßow and clipping. With a delay present, the output gain would be reduced before the delayed sound arrives, and a reduced output gain would be applied to the data, preventing overßow and clipping.

It is important to distinguish the use of the input level offset. This value only changes the displayed level, the corresponding output level look-up from the I/O Curve, and the gain computation. In this way, the input level offset serves only to change the position on the I/O Curve from which the gain is computed.

MDT UserÕs Manual 66

The Gain Adjust Algorithm

In the Gain Adjust computation, the compute level box depicts the computation of the input level from the sound samples. The compute level computation is depicted in the ßowchart:

input

absolute

value

abs

level > abs

yes

decay <– attack decay

decay <– release decay

level <– decay • level + (1 - decay) • abs

new level

This ßowchart shows that the absolute value of each sound sample is Þrst compared with the previously computed level. If the absolute value is greater than the previously computed level, then a decay value corresponding to the attack time is used, otherwise a decay value corresponding to the release time is used. (The decay values are positive and slightly less than one, which result the proper decay or release times.) The decay value is then used to update the level value using the equation shown in the ßowchart. When the attack time is shorter that the release time, the resulting level approximates the largest instantaneous amplitudes in the data. Other settings result in levels that are less than the largest instantaneous amplitudes in the data.

MDT UserÕs Manual 67

The ÒFull BandÓ Filter Mode

The “Full Band” Filter Mode

This is the simplest computation. In this Þlter mode, the sound data is input to the Gain Adjust. The output of the Gain Adjust is multiplied by the Gain slider value for the Þnal output:

Gain slider value

input

Gain Adjust

multiply

output

The “Standard” Filter Modes

The following diagram depicts the Ò3 bandÓ and Ò5 BandÓ Þlter modes:

input

Filter 1

Filter 2

Filter n

Parametric Equalizer Filters

The input signal is Þrst split into separate bands using parametric equalizer Þlters. Each of these Þltered signals is processed by a separate Gain Adjust algorithm. Hence each band embodies separate input level computations and well as separate gain computations. The delays in each of the Gain Adjust computations are the same. Hence no phase effects are present from differing delays. After the Gain Adjust computation, the separate bands are summed together and multiplied by the Gain slider value to give the output.

Gain Adjust

sum

Gain slider value

output

multiply

MDT UserÕs Manual 68

The ÒStandardÓ Filter Modes

The center frequencies of the parametric equalizer Þlter pass bands are 140, 1120, and 8960 Hz (3 octave spacing) for the 3 Band Þlters and 40, 160, 640, 2560, and 10240 Hz (2 octave spacing) for the 5 Band Þlters.

Consider the case where the I/O Curve is a 45 degree 1:1 diagonal. In this case, all output levels will equal the scaled input levels and the resulting output gains will be unity. This means the Gain Adjust output will equal the Gain Adjust inputs. The resulting overall output will then have the transfer function characteristic of the parametric equalizer. The graphs below show the frequency response of the multiband Þlters with unity output gain.

))

)) BB

BB dd

dd ((

(( ee

ee dd

dd uu

uu tt

nn gg

gg aa

aa MM

MM gg

gg oo

oo LL

-5

-10

))

)) BB

BB dd

dd ((

(( ee

ee dd

dd uu

uu tt

nn gg

gg aa

aa MM

MM gg

gg oo

oo LL

-5

100 300 1000 3000 1000020 22050

MDT 2.0 3 band transfer characteristic

FFFFrrrreeeeqqqquuuueeeennnnccccyy

MDT 2.0 5 band transfer characteristic

-10 100 300 1000 3000 1000020 22050

FFFFrrrreeeeqqqquuuueeeennnnccccyy

MDT UserÕs Manual 69

The ÒAPÓ Filter Modes

The “AP” Filter Modes

In some cases, the ±0.3 dB of passband ripple in the parametric equalizer

Þlters of the standard Þlter modes are not desirable. The AP Þlter modes do not have these artifacts provided certain limitations can be met. The following diagram depicts the Ò3 band APÓ and Ò5 Band APÓ Þlter modes:

input

Filter 1

Filter 2

Filter n

Parametric Equalizer Filters

Gain Adjust

sum

Gain slider value

multiply

output

-1

This diagram is the same as the standard Þlter mode diagram except for the additional data paths show as heavier lines. Consider the following subdiagram:

Gain Adjust

-1

The triangle near the -1 shows the signal is multiplied by -1. In the case where the I/O Curve is a 45 degree 1:1 diagonal, the output of the Gain Adjust is identically equal to the input. Therefore the output of the subdiagram is zero. Referring now back to the larger diagram, the only input to the ÒsumÓ is directly from the overall input, in which case, the output of the AP Þlter mode is simply the Gain slider applied to the input with no parametric equalizer Þlters artifacts.

When the I/O Curve deviates from a 45 degree 1:1 diagonal, output occurs from the sub-diagram, and the characteristics of the re-combined signal depend on the phase characteristics of the parametric equalizer Þlters. SpeciÞcally, these Þlters are designed so that there is a zero degree phase shift in the center of each pass band. Consequently, a gain increase indicated by the I/O Curve results in a gain increase in the overall output

MDT UserÕs Manual 70

Clip Sentry

and a gain decrease indicated by the I/O Curve results in a gain decrease in the overall output.

In this way, the AP Þlter modes are able to accomplish compression and expansion computations without artifacts from the parametric equalizer Þlters.

However, these effects are limited to the I/O Curve operating within plus and minus 12 dB of the 45 degree 1:1 diagonal. Operating above +12 dB of the diagonal causes the parametric equalizer artifacts to again dominate the output as they would in the non-AP case. This is not a serious problem. Operating below -12 dB is more of a problem: Because there is a zero degree phase shift in the center of each pass band, these frequencies will be handled properly. However, the phase changes in the crossover and stop band of each Þlter will cause the sound at these frequencies to not be correctly subtracted, leaving a signiÞcantly audible sound in the output.

Clip Sentry

Clip Sentry is a high speed digital limiter designed to prevent clipping by a reducing gain only when clipping is about it occur.

When Clip Sentry is activated by pressing the Clip Sentry button, the audio data is routed through a new buffer, creating delayed output data. Before each sample is put into the buffer, it is multiplied by the current gain. If an clipping occurs, then the current gain is gradually reduced so that when the culprit audio data appears at the output end of the buffer, the new current gain does not create clipping. The current gain is then gradually restored using a release time algorithm.

MDT UserÕs Manual 71

Stereo Sound Processing

The current gain is a combination of gain from the gain curve and the gain slider. The Clip Sentry processing occurs in the sequence described in the diagram:

Gain Curve gain increase and

Gain Slider.

Compressor process with Gain reduction, only, from Gain Curve.

CLIP SENTRY

From this diagram, you see that the Gain Curve is broken up into two parts. The Þrst part is a new curve that has gain reduction only. This reduction is compensated for by the second part, a gain increase after Clip Sentry. Hence, the data coming into Clip Sentry is never clipped. The only existing limitation of MDT 4.00 is that the maximum curve gain plus the Gain Slider cannot exceed +48dB.

Clip Sentry can attenuate the gain by as much as -30dB to stop clipping.

Stereo Sound Processing

The left and right channels of stereo signals are processed completely separately except for a single exception: they both share the same levels. The signal level computation is described in the Þrst section of this chapter using the compute level ßowchart. In the case of stereo data, the data presented to the compute level algorithm alternates between the left and right channels: L, R, L, R, L, ...

As a result of this arrangement, the same gain will be applied to both channels of the stereo data at any instant in time.

Another result is that incorrect compression/expansion results will occur if the two channels contain differing material, or if the channels are not scaled relative to one-another. In these cases, the louder channel (over the period of the time scales involved) will dominate the computation.

MDT UserÕs Manual 72

Symbols

“Soft Knee” Compressor 17 “soft knee” compressor 36 “Tube” Compander 18, 36 “tube” companders 37

Numerics

3 Band 56 3 band 68 3 Band AP 57 3 band AP 70 5 Band 57, 68 5 Band AP 57, 70

AP Filter Modes 70 AP mode 40 Attack Slider 53 Attack Time 31 attack time 19 auto read 50 auto touch 50 Automation 49, 53

Bypass Button 54

Clip 48 clip light 48 Clip Sentry 48, 71 Clip Sentry Buf Len 48 Clip Sentry Buf Len (mS) slider 55 Clip Sentry Button 54 Clip Sentry Release 48 Clip Sentry Release (mS) slider 55 Clipping Indicator 55 Compare Button 62 Compression 13 compression ratio 14, 30 Compressor 30 Compressor with Noise Gate 35 Control Surface Support 56

De-esser 45 delay 48 Delay Window 56 Delete Settings… 29

MDT UserÕs Manual lxxiii

digital ﬁlters 40 DSP Plug-ins 22 Dynamic EQ 47 dynamic range 13, 30

effect of changing attack time 19 effect of changing release time 19 Expander/Gate 34 expansion 18

Filter Mode Menu 56 Filter Modes 40, 68 ﬁlter pass band center frequencies 69 Flat 43 Flat Button 58 Flat button 49 Full Band 56 Full Band Filter Mode 68

Gain Adjust Algorithm 65 gain reduction 14, 30 Gain Slider 58 Gain slider 31

high speed digital limiter 48

lxxiv MDT UserÕs Manual

I/O Curve 23, 25, 66 I/O Curve position and gain 26 In/Out Grid 15, 16, 25 input level offset 66 Input Level Offset Arrows 27 Input Offset 43, 44 Input Offset Adjust Arrows 58 Input Offset Arrow 50 Input Offset Display 28 Input Offset Levels 49 Installing The JVP 11 inverse gain functions 24 Inverted Gain Curves 51

Levelx 50 look-ahead peak averaging 22 lower terminator 24, 35

MDT As A Compressor 15 MDT Basics 21 mixing 13 Multiband Applications 39 multiband center frequencies 69 Multiband Compressor 40 multiband mode 39 Multiband Peak Level Indicators 39

Owner Registration 11

Peak Level Indicator 22, 28 processing algorithms 65 pumping 19

Ratio 14 Release Time 31 release time 19, 22 Reset 43 Reset Button 61 Reset button 49 Reset Settings 29

Save Settings As… 29 Setting Menu 28 Settings menu 49 Single Band Applications 30 Spectral Enhancer 45, 46 Stereo Sound Processing 72

TDM Settings 62 Technical Support 11 Theory of Operation 65 Threshold 14 threshold 24 Tonal Balance 43 Tonal Balance In Multiband Mode 42 transfer characteristic 23 Tutorial 21

upper terminator 24

MDT UserÕs Manual lxxv

Variable 43, 44 Variable Button 63 Variable button 49

lxxvi MDT UserÕs Manual

ANTARES MDT Owner’s Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Welcome!

Table of Contents

How To Use This Manual

The Contents Of The Manual

Software Notes

Owner Registration

Installing MDT

Technical Support

Understanding Compression

Ratio And Threshold

MDT As A Compressor

The In/Out Grid

Attack And Release Times

MDT In The TDM Environment

CHAPTER 3 MDT Tutorial

Lesson 1: MDT Basics

About DSP Plug-ins

The Peak Level Indicator

The I/O Curve

The In/Out Grid

The Input Offset Arrows

The Setting Menu

Lesson 2: Single Band Applications

Compressor

Attack and Release Times

Expander/Gate

Example 3: Full mix

Lesson 3: Multiband Applications

Multiband Peak Level Indicators

The Filter Modes

Multiband Compressor

Managing Tonal Balance In Multiband Mode

What is the Tonal Balance Problem?

How To Achieve Tonal Balance

MDT As A Spectral Enhancer

De-esser

Spectral Enhancer

Dynamic EQ

Lesson 4: Clip Sentry

Lesson 5: Using Automation

New Possibilities

Inverted Gain Curves

CHAPTER 4 MDT Reference

Attack Slider

Automation

Bypass Button

Clip Sentry Button

Clip Sentry Buf Len (mS) slider

Clip Sentry Release (mS) slider

Clipping Indicator

Control Surface Support

Delay Window

Filter Mode Menu

Flat Button

Gain Slider

Input Offset Arrows

In/Out Display

In/Out Grid

Release Slider

Reset Button

Setting Menu

TDM Settings and the Compare Button

Thresholds And Terminators

Variable Button

CHAPTER 5 Theory of Operation

The Gain Adjust Algorithm

The “Full Band” Filter Mode

The “Standard” Filter Modes

The “AP” Filter Modes

Clip Sentry

Stereo Sound Processing