Samson MIXPAD User Manual

Produced by

On The Right Wavelength

for Samson Technologies Corp.

Printed February, 1997

Samson Technologies Corp. 575 Underhill Blvd. P.O. Box 9031 Syosset, NY 11791-9031 Phone: 1-800-3-SAMSON (1-800-372-6766) Fax: 516-364-3888

Introduction 1

MIXPAD Features 2

Guided Tours 4

MIXPAD 12/9 Channels 4 MIXPAD 12/9 Main Section 8 MIXPAD 12/9 Jackfield 10 Connecting the MIXPAD 4 Carrying Strap 11 MIXPAD 4 Channels 12 MIXPAD 4 Main Section 16 MIXPAD 4 Jackfield 18

Connecting the MIXPAD 19 Setting Up and Using the MIXPAD 22 Setting the Correct Gain Structure 23 Grounding Techniques 26 Using Pan/Balance 28 Using Equalization 30 Using Aux Sends and Returns 32 Appendix A: Operating the

MIXPAD 12/9 off Battery Power 34 MIXPAD 12/9 Specifications 36 MIXPAD 4 Specifications 37

Table of Contents

Introduction

Congratulations on your purchase of the Samson MIXPAD! One of the smallest mixers ever made, the MIXPAD provides excellent sound quality and a wealth of features normally found only in full-size units. Although it has been designed for easy operation, we suggest you take some time to go through these pages so you can fully understand how we’ve implemented a number of unique functions.

This manual covers three models: the MIXPAD 12, MIXPAD 9, and MIXPAD 4. The first two of these are identical apart from the fact that the MIXPAD 12 provides six monophonic and three stereo input channels (for a total of twelve channels), while the MIXPAD 9 provides three monophonic and three stereo input channels (for a total of nine channels). The MIXPAD 4 provides two monophonic input channels and one stereo input channel (for a total of four channels) and offers a slightly different feature set (such as three-band equalization and independent channel phantom power switches). Because of their unusually small size and portability, all three models are well-suited for specialized applications such as videography, remote site recording, ENG (Electronic News Gathering), or audio coverage of fast-paced outdoor events such as sports shows.

In these pages, we’ll provide you with an overview of the unit’s features, followed by a guided tour of the MIXPAD channels, main section and jackfield. Then we’ll describe how to set up your MIXPAD, including instructions on how to set the optimum gain structure. Next, we’ll cover a number of specific MIXPAD functions (such as panning, equalization, and auxiliary sends and returns) in detail. Finally, we’ll wrap things up with full specifications. You’ll also find a warranty card enclosed— please don’t forget to fill it out and mail it so that you can receive online technical support and so we can send you updated information about these and other Samson products in the future.

SPECIAL NOTE: Should your MIXPAD ever require servicing, a

Return

Authorization

(RA) number is necessary. Without this number, the unit will not be accepted. Please call Samson at 1-800-372-6766 for a Return Authorization number prior to shipping your unit. Please retain the original packing materials and, if possible, return the unit in its original carton and packing materials.

MIXPAD Features

The compact design of the MIXPAD belies an extraordinary versatility. Add excellent sound quality to the equation, and you’ve got a product which is equally useful as a live performance mixer and for field recording applications. Here are some of the MIXPAD’s main features:

• In the MIXPAD 12, a total of twelve input channels (including three stereo channels); in the MIXPAD 9, a total of nine input channels (including three stereo channels); in the MIXPAD 4, a total of four input channels (including one stereo channel). Monophonic channels provide electronically balanced inputs that can be used for microphone or line-level input, while stereo channels are ideal for line-level sources such as outboard signal processors; CD players; tape or cassette recorders; stereo drum machines; and keyboards and MIDI tone modules.

• An electronically balanced main stereo output for connection to a power amplifier or tape recorder.

• A dedicated Tape/CD input for playback of prerecorded material.

• In the MIXPAD 12 and MIXPAD 9, two auxiliary sends and two stereo auxiliary returns (which can be used as four monophonic returns). Aux send 1 is pre-fader (but post-equalizer), making it ideal for use as a headphone or monitor cue mix, while Aux send 2 is post-fader and post-equalizer.

• In the MIXPAD 4, one auxiliary send and one stereo auxiliary return (which can be used as two monophonic returns), with the aux send post-fader and post-equalizer.

• In the MIXPAD 12 and MIXPAD 9, independent 2-band equalization for each channel, with 15 dB of cut or boost for low (100 Hz) and high (10 kHz) frequencies.

• In the MIXPAD 4, independent 3-band equalization for each channel, with 15 dB of cut or boost for low (80 Hz) and high (12 kHz) frequencies, and 12 dB of cut or boost for the mid (2.5 kHz) frequency.

MIXPAD Features

• Constant level pan controls for placing each monophonic channel in the left-right stereo spectrum, as well as balance controls that allow you to blend the relative levels of stereo inputs.

• Mic input trims that are continuously adjustable from +4 to -50 dB, making it possible to use the MIXPAD with a wide variety of microphones.

• The MIXPAD 12 and MIXPAD 9 provide 36 volts of phantom power to all mic inputs, while the MIXPAD 4 provides 18 volts of phantom power (with independent switches for each of its two mic input channels), making it possible to use most condenser and dynamic mics, as well as active DI (Direct Injection) boxes.

• Peak LEDs for the left and right main outputs, showing you when signal is overloading or near overloading.

• Center detents for all pan, balance, and EQ controls, making it easy to access them in low-light situations such as live performance.

• Convenient front-panel Power switch, Power LED and dedicated headphone jack.

• The MIXPAD 4 runs on either AC or battery power (requiring just two standard 9 volt batteries—three if you need phantom power), with optional battery power available for the MIXPAD 12 and MIXPAD 9 (see Appendix A on page 34), enabling the unit to be used for ENG (Electronic News Gathering), field broadcast and recording purposes. In the MIXPAD 4, the front-panel Power LED also indicates battery strength.

• The MIXPAD 4 includes a handy carrying strap for easy portability.

• Last but certainly not least, affordability. The Samson MIXPAD has been designed from the ground up to provide versatility and excellent sound quality at a cost-conscious price.

Guided Tour MIXPAD 12 /MIXPAD 9 Channels

LEVEL

LINE

TRIM

-50

-10

MIC

MONO

Mono Channel

LOW

HIGH

+15-15

+10

PAN

AUX 2

AUX1

PRE

+10

BALANCE

AUX 2

AUX1

PRE

+10

LEVEL

LOW

HIGH

+15-15

Stereo Channel

Guided Tour -

MIXPAD 12 / MIXPAD 9 Channels

1: Mic inputs - Provided in monophonic channels only (channels 1 - 6 in the MIXPAD 12 and channels 1 - 3 in the MIXPAD 9). Use these electronically balanced XLR jacks to connect microphones to any of the MIXPAD’s monophonic channels. These are intended to accept signal from low-level, low-impedance mics but can also be used for signal from other sources (such as direct injection boxes) if the channel’s Trim control is turned down (see #2 below). All MIXPAD 12 and MIXPAD 9 XLR mic connectors are 36 volt phantom powered, enabling you to connect a wide variety of condenser or dynamic microphones. WARNING: Do not connect a channel’s microphone input if you already have something connected to its line input; each channel is designed to accept only one source or the other.

2: Trim - Provided in monophonic channels only (channels 1 - 6 in the MIXPAD 12 and channels 1 - 3 in the MIXPAD 9). This knob determines the input level of the connected mic or line signal. Continuously adjustable from +4 dB to -50 dB, the input trim is at unity gain (no boost or cut) when set to the “0” (9 o’clock) position. The input signal is boosted when the trim is turned to the right of “0” and attenuated when turned to the left of “0.” For information on how to properly set this for each channel, see the section on page 23 entitled “Setting The Correct Gain Structure.”

3: Line inputs - Use these standard 1/4" jacks to connect line-level sources such as synthesizers, drum machines, CD players, tape decks, or effects processors to any of the MIXPAD’s mono or stereo channels. The line input jacks for monophonic channels (channels 1 - 6 in the MIXPAD 12 and channels 1 - 3 in the MIXPAD 9) are electronically balanced, so you should use balanced three-conductor cabling and Tip/Ring/Sleeve (TRS) plugs wherever possible (unbalanced twoconductor plugs can also be inserted into these inputs, but you’ll get better signal quality and less outside noise and hum if you use balanced lines). WARNING: Do not connect a channel’s line input if you already have something connected to its microphone input; each channel is designed to accept only one source or the other.

The line input jacks for stereo channels (channels 7 - 12 in the MIXPAD 12 and channels 4 - 9 in the MIXPAD 9) are unbalanced. When connecting only one monophonic signal to stereo channels, use the left (even-numbered) input; the MIXPAD will then treat that channel as if it is a mono channel, allowing the signal to be panned (using the

Guided Tour MIXPAD 12 / MIXPAD 9 Channels

Balance control)—see the “Using Pan/Balance” section on page 28 for more information. See the “Connecting The MIXPAD” section on page 19 for additional information on how best to use channel inputs.

4: Equalizer (violet) - These knobs determine the amount of boost or attenuation in each of two frequency areas. The high and low frequency knobs provide 15 dB of cut or boost at 10 kHz and 100 Hz, respectively. Both frequency controls utilize a shelving curve. In stereo channels, EQ settings affect both the left and right inputs, although the signals remain separate. A center detent in each knob (at the “0” position) indicates no boost or attenuation (that is, flat response). As each knob is turned clockwise from the “0” position, the frequency area is boosted; as it is turned counterclockwise from the “0” position, the frequency area is attenuated. For more information on the application of EQ, see the “Using Equalization” section on page 30.

5: Auxiliary sends (blue) - These knobs allow you to route signal to either or both of the MIXPAD’s two monophonic Auxiliary outputs. These are typically used to create submixes (for example, a headphone cue mix) and to feed signal from single or multiple channels to outboard effects devices. At the “0” (2 o’clock) position, the signal is routed with unity gain (that is, no boost or attenuation). As each knob is turned clockwise from the “0” position, the signal is boosted; as it is turned counterclockwise from the “0” position, it is attenuated. Aux send 1 is post-eq but

pre-fade

; that is, the level of the signal is determined solely by its EQ settings and by its Trim control; see #2 on the previous page. Aux send 2 is post-eq and

post-fade

; that is, the level of the signal is determined by the channel’s Trim control, its EQ settings, and the position of its Level control. See the “Using Aux Sends and Returns” section on page 32 for more information.

6: Pan (green) - Provided in monophonic channels only. This knob allows you to place the input signal anywhere in the left-right stereo spectrum, while keeping the overall signal level constant. When the knob is placed at its center (detented) position, the signal is sent equally to both left and right outputs. When moved left of center, less signal is sent to the right output and more signal is sent to the left output (making the sound appear left of center) and when moved right of center, less signal is sent to the left output and more signal is sent to the right output (making the sound appear right of center). To route a signal hard left or right, place the pan knob either fully counterclockwise or fully clockwise.

7: Balance (brown) - Provided in stereo channels only. When both inputs are connected to a stereo channel, the upper input signal (channels 7, 9, and 11 in the MIXPAD 12 and channels 4, 6, and 8 in the MIXPAD 9) is automatically panned hard left and the lower input signal (channels 8, 10, and 12 in the MIXPAD 12 and channels 5, 7, and 9 in the MIXPAD 9) is automatically panned hard right. In this case, the “Balance” knob controls the relative levels of the paired input signals. When the knob is placed at its center (detented) position, both signals are at equal strength. When moved left of center, the upper input remains at the same strength but the lower input is attenuated; when the knob is moved right of center, the lower input remains at the same strength but the upper input is attenuated. When placed fully counter-clockwise, only the upper input is heard (panned hard left); when placed fully clockwise, only the lower input is heard (panned hard right). In stereo channels where only the upper input is connected, the Balance knob works like a mono channel Pan control; see #6 on the previous page for details. For more information, see the “Using Pan/Balance” section on page 28 in this manual.

8: Level (white) - In mono channels (or in stereo channels where only the upper input is connected), this knob determines the signal level being sent to the main output as well as affecting the signal level being sent to Aux send 2. In stereo channels, this knob simultaneously controls the level of both the upper and lower inputs (the

relative

levels of the two can be adjusted with the Balance knob, as described above) as well as the signal level being sent to Aux send 2. In practice, you will use the channel Level controls to continuously adjust the levels of the various signals being blended together by the MIXPAD. The “0” position of the knob indicates unity gain (no level attenuation or boost). Moving the knob counterclockwise from the “0” position causes the signal to be attenuated (at the very bottom, it is attenuated infinitely— in other words, there is no sound); moving it clockwise from the “0” position causes the signal to be boosted by as much as 10 dB.

For best signal-to-noise ratio, all Level controls for channels carrying signal should generally be kept at or near the “0” position. Channels that are unused should have their gain controls kept fully counterclockwise at their (minimum) level. See the “Setting the Correct Gain Structure” section on page 23 in this manual for more information.

Guided Tour -

MIXPAD 12 / MIXPAD 9 Channels

Guided Tour - MIXPAD 12 / MIXPAD 9 Main Section

1: Tape/CD inputs (L, R) - Use this set of dual RCA jacks to connect the outputs of a tape or CD player to the MIXPAD. In the MIXPAD 12, signal connected here appears at stereo channel 11/12 and is mixed at unity gain with any line input signal connected to channel 11/12. In the MIXPAD 9, signal connected here appears at stereo channel 8/9 and is mixed at unity gain with any line input signal connected to channel 8/9.

POWER

LEFT RIGHT

TAPE/CD

MAIN LEVEL

LEFT RIGHT

+10

AUX RET. 3/4

AUX RET.1/2

Guided Tour - MIXPAD 12 /

MIXPAD 9 Main Section

2: Left/Right Peak LEDs (red) - These warning lights indicate an overload situation. They light whenever the main left or right output signal is 5 dB short of clipping. To stop them from lighting (and to eliminate the accompanying sonic distortion), turn down the Main Level control (see #7 below). See the “Setting the Correct Gain Structure” section on page 23 in this manual for more information.

3: Power LED - This LED lights steadily red whenever the MIXPAD is powered on.

4: Power on-off switch - As you may have guessed, this is what you use to turn the MIXPAD on and off. To avoid potential damage to your speakers, turn the unit on

before

you turn on any connected power

amps—and turn it off

after

the power amps are turned off.

5: Stereo Auxiliary Return Level (tan) - These knobs determine the input level of signal arriving via the MIXPAD’s two stereo Auxiliary returns (1/2 and 3/4). Each return is at unity gain (no boost or attenuation) when set to the “0” (2 o’clock) position. The input signal is boosted when the knob is turned to the right of “0” and attenuated when turned to the left of “0.” For information on how to properly set these, see the sections in this manual entitled “Setting the Correct Gain Structure” and “Using the Aux Sends and Returns” (pages 23 and 32). Auxiliary return signal is automatically routed to the Main L/R output.

6: Headphone jack - Connect any standard stereo headphones to this jack (via a standard 1/4" TRS plug) for private monitoring of the main stereo output. The built-in MIXPAD headphone preamp delivers 100 mw at 600 ohms.

7: Main Level (white) - This knob determines the final output signal level—you can think of this as being the “master fader.” Signals from all channels and Auxiliary returns, as well as the Tape/CD input are routed here just before leaving the MIXPAD via its left and right main output jacks. The “0” position of the knob indicates unity gain (no level attenuation or boost). Moving the knob counterclockwise from the “0” position causes the signal to be attenuated (at the very bottom, it is attenuated infinitely—in other words, there is no sound). Moving it clockwise from the “0” position causes the signal to be boosted by as much as 10 dB. For more information, see the “Setting The Correct Gain Structure” section on page 23 in this manual.

Guided Tour MIXPAD 12 / MIXPAD 9 Jackfield

1: Aux Sends (1, 2) - These unbalanced 1/4" outputs allow you to route signal from each of the two discrete Aux Sends to external devices such as effects processors. Aux send 1 is pre-fade but post-EQ, while Aux send 2 is both post-fade and post-EQ. See the “Using the Aux Sends and Returns” section on page 32 in this manual for more information.

2: Main out (L, R) - These are the MIXPAD’s main outputs. You’ll usually use these to connect the MIXPAD to a tape recorder or to a power amp and loudspeakers. The Main out jacks are electronically balanced, so you should use balanced three-conductor cabling and TRS plugs wherever possible (unbalanced two-conductor plugs can also be inserted into these outputs, but you’ll get better signal quality and less outside noise and hum if you use balanced lines). See the “Connecting the MIXPAD” section on page 19 in this manual for more information.

3: Aux Returns (1/2, 3/4) - These inputs allow you to route signal from external devices such as effects processors to either of the MIXPAD's two stereo Aux Returns. These jacks accept unbalanced 1/4" TRS plugs, with the tip carrying the left signal and the ring carrying the right signal (sleeve is common ground). See the “Using the Aux Sends and Returns” section on page 32 in this manual for more information.

AUX

SEND 1

AUX

SEND 2

RIGHT

OUTPUT

BALANCED

+4dBu

AUX

RETURN

1/2

AUX

RETURN

3/4

LEFT

+ 28 hidden pages