Yamaha Audio MG4FX, MG12 User Manual

MIXING CONSOLE

Owner’s Manual

Making the Most Of Your Mixer

Pages 6 to 16

PRECAUTIONS

PLEASE READ CAREFULLY BEFORE PROCEEDING

* Please keep this manual in a safe place for future reference.

WARNING

Always follow the basic precautions listed below to avoid the possibility of serious injury or even death from electrical shock, short-circuiting, damages, ﬁre or other hazards. These precautions include, but are not limited to, the following:

Power supply/Power cord

• Only use the voltage speciﬁed as correct for the device. The required voltage is printed on the name plate of the device.

• Use only the speciﬁed AC power adaptor (PA-20 or an equivalent recommended by Yamaha).

• Do not place the power cord near heat sources such as heaters or radiators, and do not excessively bend or otherwise damage the cord, place heavy objects on it, or place it in a position where anyone could walk on, trip over, or roll anything over it.

Do not open

• Do not open the device or attempt to disassemble the internal parts or modify them in any way. The device contains no user-serviceable parts. If it should appear to be malfunctioning, discontinue use immediately and have it inspected by qualiﬁed Yamaha service personnel.

Water warning

• Do not expose the device to rain, use it near water or in damp or wet conditions, or place containers on it containing liquids which might spill into any openings.

• Never insert or remove an electric plug with wet hands.

If you notice any abnormality

• If the power cord or plug becomes frayed or damaged, or if there is a sudden loss of sound during use of the device, or if any unusual smells or smoke should appear to be caused by it, immediately turn off the power switch, disconnect the electric plug from the outlet, and have the device inspected by qualiﬁed Yamaha service personnel.

• If this device or the AC power adaptor should be dropped or damaged, immediately turn off the power switch, disconnect the electric plug from the outlet, and have the device inspected by qualiﬁed Yamaha service personnel.

CAUTION

Always follow the basic precautions listed below to avoid the possibility of physical injury to you or others, or damage to the device or other property. These precautions include, but are not limited to, the following:

Power supply/Power cord

• Remove the electric plug from the outlet when the device is not to be used for extended periods of time, or during electrical storms.

• When removing the electric plug from the device or an outlet, always hold the plug itself and not the cord. Pulling by the cord can damage it.

•To avoid generating unwanted noise, make sure there is 50 cm or more between the AC power adaptor and the device.

• Do not cover or wrap the AC power adaptor with a cloth or blanket.

Location

• Before moving the device, remove all connected cables.

•Avoid setting all equalizer controls and faders to their maximum. Depending on the condition of the connected devices, doing so may cause feedback and may damage the speakers.

• Do not expose the device to excessive dust or vibrations, or extreme cold or heat (such as in direct sunlight, near a heater, or in a car during the day) to prevent the possibility of panel disﬁguration or damage to the internal components.

• Do not place the device in an unstable position where it might accidentally fall over.

• Do not use the device in the vicinity of a TV, radio, stereo equipment, mobile phone, or other electric devices. Otherwise, the device, TV, or radio may generate noise.

Connections

• Before connecting the device to other devices, turn off the power for all devices. Before turning the power on or off for all devices, set all volume levels to minimum.

Handling caution

• Do not insert your ﬁngers or hand in any gaps or openings on the device.

•Avoid inserting or dropping foreign objects (paper, plastic, metal, etc.) into any gaps or openings on the device. If this happens, turn off the power immediately and unplug the power cord from the AC outlet. Then have the device inspected by qualiﬁed Yamaha service personnel.

• Do not use the device or headphones for a long period of time at a high or uncomfortable volume level, since this can cause permanent hearing loss. If you experience any hearing loss or ringing in the ears, consult a physician.

• Do not rest your weight on the device or place heavy objects on it, and avoid use excessive force on the buttons, switches or connectors.

MG12/4FX

XLR-type connectors are wired as follows (IEC60268 standard): pin 1: ground, pin 2: hot (+), and pin 3: cold (–).

Insert TRS phone jacks are wired as follows: sleeve: ground, tip: send, and ring: return.

Yamaha cannot be held responsible for damage caused by improper use or modiﬁcations to the device.

Always turn the power off when the device is not in use.

Even when the power switch is in the “STANDBY” position, electricity is still ﬂowing to the device at the minimum level. When you are not using the device for a long time, make sure you unplug the power cord from the wall AC outlet.

The performance of components with moving contacts, such as switches, volume controls, and connectors, deteriorates over time. Consult qualiﬁed Yamaha service personnel about replacing defective components.

Copying of the commercially available music data and/or digital audio ﬁles is strictly prohibited except for your personal use.

Illustration examples shown herein are for explanatory purposes only, and may not match actual appearance during operation.

The company names and product names in this Owner’s Manual are the trademarks or registered trademarks of their respective companies.

IMPORTANT NOTICE FOR THE UNITED KINGDOM

Connecting the Plug and Cord

IMPORTANT. The wires in this mains lead are coloured in accordance with the following code:

BLUE : NEUTRAL

BROWN : LIVE As the colours of the wires in the mains lead of this apparatus may not correspond with the coloured makings identifying the terminals in your plug proceed as follows: The wire which is coloured BLUE must be connected to the terminal which is marked with the letter N or coloured BLACK. The wire which is coloured BROWN must be connected to the terminal which is marked with the letter L or coloured RED. Making sure that neither core is connected to the earth terminal of the three pin plug.

•This applies only to products distributed by Yamaha-Kemble Music (U.K.) Ltd. (2 wires)

FCC INFORMATION (U.S.A.)

1. IMPORTANT NOTICE: DO NOT MODIFY THIS UNIT!

This product, when installed as indicated in the instructions contained in this manual, meets FCC requirements. Modiﬁcations not expressly approved by Yamaha may void your authority, granted by the FCC, to use the product.

2. IMPORTANT: When connecting this product to accessories

and/or another product use only high quality shielded cables. Cable/s supplied with this product MUST be used. Follow all installation instructions. Failure to follow instructions could void your FCC authorization to use this product in the USA.

3. NOTE: This product has been tested and found to comply with

the requirements listed in FCC Regulations, Part 15 for Class “B” digital devices. Compliance with these requirements provides a reasonable level of assurance that your use of this product in a residential environment will not result in harmful interference with other electronic devices. This equipment generates/uses radio frequencies and, if not installed and used according to the instructions found in the users manual, may cause interference harmful to the operation of other electronic devices. Compliance with FCC regulations does not guarantee

that interference will not occur in all installations. If this product is found to be the source of interference, which can be determined by turning the unit “OFF” and “ON”, please try to eliminate the problem by using one of the following measures: Relocate either this product or the device that is being affected by the interference. Utilize power outlets that are on different branch (circuit breaker or fuse) circuits or install AC line ﬁlter/s. In the case of radio or TV interference, relocate/reorient the antenna. If the antenna lead-in is 300 ohm ribbon lead, change the lead-in to co-axial type cable. If these corrective measures do not produce satisfactory results, please contact the local retailer authorized to distribute this type of product. If you can not locate the appropriate retailer, please contact Yamaha Corporation of America, Electronic Service Division, 6600 Orangethorpe Ave, Buena Park, CA90620 The above statements apply ONLY to those products distributed by Yamaha Corporation of America or its subsidiaries.

* This applies only to products distributed by YAMAHA CORPORATION OF AMERICA. (class B)

MG12/4FX

Introduction

Thank you for your purchase of the YAMAHA MG12/4FX mixing console. The MG12/4FX features input channels suitable for a wide range of usage environments, and includes high-quality built-in digital effects that can provide some very serious sound. The mixer combines ease of operation with support for multiple usage environments.

Please read through this manual carefully before beginning use, so that you will be able to take full advantage of this mixer’s superlative features and enjoy trouble-free operation for years to come.

Introduction 4

Contents .............................................................. 4

Features ............................................................... 4

Before Turning on the Mixer ................................. 5

Tu r ning the Power On .......................................... 5

Making the Most Of Your Mixer 6

1. A Place For Everything and

Everything In Its Place.................................... 6

2. Where Your Signal Goes Once

It’s Inside the Box ........................................... 9

3. The First Steps in Achieving

Great Sound ................................................. 10

4. External Effects, Monitor Mixes,

and Groups ................................................... 12

5. Making Better Mixes..................................... 15

Front & Rear Panels 17

Channel Control Section .................................... 17

Master Control Section ...................................... 19

Rear Input/Output Section ................................. 21

Setting Up 23

Setup Procedure ................................................ 23

Setup Examples ................................................. 23

Rack Mounting ................................................... 25

Appendix 26

Speciﬁcations ..................................................... 26

Dimensional Diagrams ....................................... 28

Block Diagram and Level Diagram .................... 29

Features

Input Channels................................ page 21

With up to six mic/line inputs or up to four stereo inputs, the MG12/4FX can simultaneously connect to a wide range of devices: microphones, line-level devices, stereo synthesizers, and more. For example, you can connect four microphones and four stereo devices, or six microphones and two stereo devices.

Phantom Power (+48 V).................. page 19

A single switch turns phantom power on or off for all six mic inputs. Phantom power enables easy connection to condenser microphones that require external power.

High-quality digital effects............. page 20

With digital effects built in, the MG12/4FX can deliver a wide range of sound variations all by itself. The unit also includes an EFFECT SEND jack that can be used to connect an external effector.

AUX Sends and Stereo

AUX Return................................ page 17, 19

You can use the AUX SEND jack to feed the post-fader signal to an external signal processor, and then return the processed stereo signal through the RETURN jack. Alternatively, you can use the PRE switch on each channel to send that channel’s pre-fader signal out through the AUX SEND jack for monitoring.

Rack Mounting................................ page 25

The mixer provides two metal rack-mount supports, and integrates easily into a wide variety of setups.

MG12/4FX

Introduction

Before Turning on the Mixer

Be sure that the mixer’s power switch is in the

STANDBY position.

Use only the PA-20 adaptor included with this mixer. Use of a different adaptor may result in equipment damage, overheating, or ﬁre.

Connect the power adaptor to the AC ADAPTOR IN

connector (

the fastening ring clockwise (2) to secure the connec-

tion.

) on the rear of the mixer, and then turn

Turning the Power On

Press the mixer’s power switch to the ON position. When

you are ready to turn the power off, press the power switch to

the STANDBY position.

Note that trace current continues to ﬂow while the switch is in the STANDBY position. If you do not plan to use the mixer again for a long while, please be sure to unplug the adaptor from the wall outlet.

Plug the power adaptor into a standard household

power outlet.

• Be sure to unplug the adaptor from the outlet

when not using the mixer, or when there are lightning storms in the area.

• To avoid generating unwanted noise, make sure

there is 50 cm or more between the power adaptor and the mixer.

MG12/4FX

Making the Most Of Your Mixer

■ An Introduction

You’ve got yourself a mixer and now you’re ready to use it. Just plug everything in, twiddle the controls, and away you go … right? Well, if you’ve done this before you won’t have any problems, but if this is the ﬁrst time you’ve ever used a mixer you might want to read through this little tutorial and pick up a few basics that will help you get better performance and make better mixes.

1. A Place For Everything and Everything In Its Place

1-1. A Plethora Of Connectors—What Goes Where?

Questions you’re likely to encounter when setting up a system for the ﬁrst time might include “Why all these different types of connectors on the back of my mixer?” and “What’s the difference?”.

Let’s start by taking a look at the most common connector types.

■ The Venerable RCA Pin Jack

White

Red

This is the “consumer connector,” and the one that has been most commonly used on home audio gear for many years. Also known as “phono” jacks (short for “phonogram”), but the term isn’t used much these days—besides, it’s too easily confusable with “phone” jacks, below. RCA pin jacks are always unbalanced, and generally carry a line-level signal at –10 dB, nominal. You’re most likely to use this type of connector when connecting a CD player or other home audio type source to your mixer, or when connecting the output of your mixer to a cassette recorder or similar gear.

■ The Versatile Phone Jack

The name “phone jack” arose simply because this conﬁguration was ﬁrst used in telephone switchboards. Phone jacks can be tricky because you can’t always tell what

Stereo/TRS phone plug

Mono phone plug

type of signal they’re designed to handle just by looking at them. It could be unbalanced mono, unbalanced stereo, balanced mono, or an insert patch point. The connector’s label will usually tell you what type of signal it handles, as will the owner’s manual (you do keep your manuals in a safe place, don’t you?). A phone jack that is set up to handle balanced signals is also often referred to as a “TRS” phone jack. “TRS” stands for Tip-Ring-Sleeve, which describes the conﬁguration of the phone plug used.

MG12/4FX

Making the Most Of Your Mixer

■ The Sturdy XLR

This type of connector is generally referred to as “XLR-type,” and almost always carries a balanced signal. If the corresponding circuitry is designed properly, however, XLR-type connectors will also handle unbalanced signals with no problem. Microphone

Male

Female

cables usually have this type of connector, as do the inputs and outputs of most professional audio gear.

1-2. Balanced, Unbalanced—What’s the Difference?

In a word: “noise.” The whole point of balanced lines is noise rejection, and it’s something they’re very good at. Any length of wire will act as an antenna to pick up the random electromagnetic radiation we’re constantly surrounded by: radio and TV signals as well as spurious electromagnetic noise generated by power lines, motors, electric appliances, computer monitors, and a variety of other sources. The longer the wire, the more noise it is likely to pick up. That’s why balanced lines are the best choice for long cable runs. If your “studio” is basically conﬁned to your desktop and all connections are no more than a meter or two in length, then unbalanced lines are ﬁne—unless you’re surrounded by extremely high levels of electromagnetic noise. Another place balanced lines are almost always used is in microphone cables. The reason for this is that the output signal from most microphones is very small, so even a tiny amount of noise will be relatively large, and will be ampliﬁed to an alarming degree in the mixer’s high-gain head ampliﬁer.

To summarize:

Microphones: Use balanced lines. Short line-level runs: Unbalanced lines are ﬁne if you’re in a relatively noise-free environment. Long line-level runs: The ambient electromagnetic noise level will be the ultimate deciding factor, but balanced is

best.

■ How Do Balanced Lines Reject Noise?

** Skip this section if technical details make you queasy. **

Balanced lines work on the principle of “phase cancellation”: if you add two identical signals out of phase (i.e. one signal is inverted so its peaks coincide with the troughs in the other signal), the result is … nothing. A ﬂat line. The signals cancel each other out.

Normal-phase signal.

No signal.

(Phase cancellation)

Reverse-phase signal.

MG12/4FX

Making the Most Of Your Mixer

A balanced cable has three conductors:

1) A ground conductor which carries no signal, just the “ground” or “0” reference against which the signal in the other conductors ﬂuctuates.

2) A “hot” or “+” conductor which carries the normal-phase audio signal.

3) A “cold” or “–” conductor which carries the reverse-phase audio signal.

While the desired audio signals in the hot and cold conductors are out of phase, any noise induced in the line will be exactly the same in both conductors, and thus in phase. The trick is that the phase of one signal is reversed at the receiving end of the line so that the desired audio signals become in-phase, and the induced noise suddenly ﬁnds itself out of phase. The out-of-phase noise signal is effectively canceled while the audio signal is left intact. Clever, eh?

Normal-phase signal

+ normal-phase noise.

Desired signal

with no noise.

Normal-phase signal

+ reverse-phase noise.

1-3. Signal Levels—Decibel Do’s and Don’ts

From the moment you start dealing with things audio, you’ll have to deal with the term “decibel” and its abbreviation, “dB”. Things can get confusing because decibels are a very versatile unit of measure used to describe acoustic sound pressure levels as well as electronic signal levels. To make matters worse there are a number of variations: dBu, dBV, dBm. Fortunately, you don’t need to be an expert to make things work. Here are a few basics you should keep in mind:

● “Consumer” gear (such as home audio equipment) usually has line inputs and outputs with a nominal (average) level of

–10 dB.

● Professional audio gear usually has line inputs and outputs with a nominal level of +4 dB.

● You should always feed –10 dB inputs with a –10 dB signal. If you feed a +4 dB signal into a –10 dB input you are likely to

overload the input.

● You should always feed +4 dB inputs with a +4 dB signal. A –10 dB signal is too small for a +4 dB input, and will result in

less-than-optimum performance.

● Many professional and semi-professional devices have level switches on the inputs and/or outputs that let you select –10 or

+4 dB. Be sure to set these switches to match the level of the connected equipment.

● Inputs that feature a “Gain” control—such as the mono-channel inputs on your Yamaha mixer—will accept a very wide range

of input levels because the control can be used to match the input’s sensitivity to the signal. More on this later.

MG12/4FX

Making the Most Of Your Mixer

2. Where Your Signal Goes Once It’s Inside the Box

At first glance the block diagram of even a modest mixer can look like a space-station schematic. In reality, block diagrams are a great aid in understanding how the signal flows in any mixer. Here’s a greatly simplified block diagram of a generic mixer to help you become familiar with the way these things work.

2-1. Greatly Simpliﬁed Mixer Block Diagram

Input Channel Master Section

1234 5

■ Input Channel

1 Head Amp

The very ﬁrst stage in any mixer, and usually the only stage with signiﬁcant “gain” or “ampliﬁcation.” The head amp has a “gain” control that adjusts the mixer’s input sensitivity to match the level of the source. Small signals (e.g. mics) are ampliﬁed, and large signals are attenuated.

2 Equalizer

Could be simple bass and treble controls or a full-blown 4-band parametric EQ. When boost is applied the EQ stage also has gain. You can actually overload the input channel by applying too much EQ boost. It’s usually better to cut than boost.

Signals from the mixer’s other input channels (if they are assigned to this master output or “bus”).

■ Master Section

4 Summing Ampliﬁer

This is where the actual “mixing” takes place. Signals from all of the mixer’s input channels are “summed” (mixed) together here.

5 Master Fader & Level Meter

A stereo, mono, or bus master fader and the mixer’s main output level meter. There could be several master faders depending on the design of the mixer—i.e. the number of buses or outputs it provides.

3 Channel Peak LED & Fader

The channel peak LED is your most valuable tool for setting the input “gain” control for optimum performance. Note that it is located after the head amp and EQ stage.

MG12/4FX

Making the Most Of Your Mixer

3. The First Steps in Achieving Great Sound

Before you even consider EQ and effects, or even the overall mix, it is important to make sure that levels are properly set for each individual source. This can’t be stressed enough—initial level setup is vitally important for achieving optimum performance from your mixer! Here’s why … and how.

3-1. The Head Ampliﬁer “Gain” Control Is the Key!

Let’s review our simpliﬁed mixer block diagram:

Each and every “stage” in the mixer’s signal path will add a certain amount of noise to the signal: the head amp, the EQ stage, the summing ampliﬁer, and the other buffer and gain stages that exist in the actual mixer circuit (this applies to analog mixers in particular). The thing to keep in mind is that the amount of noise added by each stage is usually not dependent to any signiﬁcant degree on the level of the audio signal passing through the circuit. This means that the bigger the desired signal, the smaller the added noise will be in relation to it. In tech-speak this gives us a better “signal-to-noise ratio”—often abbreviated as “S/N ratio.” All of this leads to the following basic rule:

To achieve the best overall system S/N ratio, amplify the input to the desired average level as early as possible in the signal path.

In our mixer, that means the head ampliﬁer. If you don’t get the signal up to the desired level at the head ampliﬁer stage, you will need to apply more gain at later stages, which will only amplify the noise contributed by the preceding stages. Just remember that too much initial gain is bad too, because it will overload our channel circuitry and cause clipping.

MG12/4FX

+ 23 hidden pages