Samson MIXPAD manuel d'utilisation

Produced by On The Right Wavelength for Samson Technologies Corp. Copyright 1996, 1997, 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 T ours 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 MIXP AD 19 Setting Up and Using the MIXP AD 22 Setting the Correct Gain Str ucture 23 Grounding T ech[...]

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 h[...]

MIXP AD F eatures 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 channel[...]

MIXP AD F eatures • 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 microph[...]

4 Guided T our - MIXP AD 12 /MIXP AD 9 Channels 1 LEVEL LINE TRIM -50 -10 0 +4 MIC L R MONO 3 4 5 6 8 2 7 Mono Channel LOW HIGH +15 -15 O +15 -15 O +10 O +10 O LR PAN AUX 2 AUX1 PRE O +10 +10 O +10 O LR BALANCE AUX 2 AUX1 PRE O +10 LEVEL LOW HIGH +15 -15 O +15 -15 O Stereo Channel[...]

5 Guided T our - MIXP AD 12 / MIXP AD 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[...]

6 Guided T our - MIXP AD 12 / MIXP AD 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 [...]

7 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 MI[...]

8 Guided T our - MIXP AD 12 / MIXP AD 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 [...]

9 Guided T our - MIXP AD 12 / MIXP AD 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)[...]

10 Guided T our - MIXP AD 12 / MIXP AD 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?[...]

The MIXPAD 4 is supplied with a handy carrying strap for easy portability. As shown in the illustration above, attach the strap to the MIXPAD 4 by placing the buckles in the connector slots and pressing them in firmly until they snap in place. Remove the carrying strap by gently squeezing together the outside buckle clips in order to extract them f[...]

12 Guided T our - MIXP AD 4 Channels HIGH +15 -15 O +12 -12 O LR PAN LINE MIC LR LEVEL BALANCE O +10 O +10 TRIM -50 -10 0 -6 -20 LINE 3L 4R +10 O AUX +10 O AUX LEVEL ∞∞ ∞ ∞ LOW +15 -15 O MID 1 2 3 4 5 6 8 7 HIGH +15 -15 O +12 -12 O LOW +15 -15 O MID[...]

13 Guided T our - MIXP AD 4 Channels 1: Mic inputs - Provided in monophonic channels only (channels 1 and 2). Use these electronically balanced XLR jacks to connect microphones to either of the MIXPAD 4’s two monophonic channels. These are intended to accept signal from low-level, low-impedance mics but can also be used for signal from other sour[...]

14 Guided T our - MIXP AD 4 Channels 4: Equalizer (violet) - These knobs determine the amount of boost or attenuation in each of three frequency areas. Each knob provides 15 dB of cut or boost at 12 kHz (High) and 80 Hz (Low) frequencies, and 12 dB of cut or boost at the Mid (2.5 kHz) frequency. The High and Low frequencies utilize shelving curves [...]

15 Guided T our - MIXP AD 4 Channels 7: Balance (brown) - Provided in the stereo channel (channels 3 - 4) only. When both inputs are connected to the stereo channel, the channel 3 input signal is automatically panned hard left and the channel 4 input signal is automatically panned hard right. In this case, the “Balance” knob controls the relati[...]

Guided T our - MIXP AD 4 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 4. Signal connected here appears at the stereo channel (channels 3 and 4) and is mixed at unity gain with any line input signal connected to channel 3/4. 2: Phantom Power switches (Ch 1, Ch 2) -[...]

Guided T our - MIXP AD 4 Main Section 3: 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 #8 below). See the “Se[...]

Guided T our - MIXP AD 4 Jackfield 1: Main out (L, R) - These are the MIXPAD 4’s main outputs. You’ll usually use these to connect the MIXPAD 4 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-[...]

19 Connecting the MIXP AD - General Suggestions The actual connections you’ll make to and from the MIXPAD will vary according to the environment you use it in and the particular equipment you have, but here are a few basic rules concerning MIXPAD connections that will apply in most situations: • In general, it’s best to make all connections w[...]

20 Connecting the MIXP AD - General Suggestions • Make one connection at a time and then monitor the incoming signal. If you hear a distinct hum or buzz, you may have a grounding problem with that particular device. See the section in this manual entitled “Grounding Techniques” (on page 26) for more information. • NEVER connect a microphone[...]

21 Connecting the MIXP AD - General Suggestions • In the MIXPAD 12 and MIXPAD 9, when connecting only one monophonic signal to a stereo channel, always use the upper input. When only the upper input is connected in a stereo channel, the MIXPAD 12/9 treats that channel as if it is a mono channel and the signal can then be panned (using the Balance[...]

22 Setting Up and Using the MIXP AD Setting up your MIXPAD is a simple procedure which takes only a few minutes: 1. Remove all packing materials (save them in case of need for future service) and decide where the unit is to be physically placed. 2. Begin by connecting the MIXPAD main left/right outputs to a tape recorder or power amp (and the amp i[...]

23 Setting the Cor rect Gain Str ucture You’re now ready to establish the correct gain structure—the key to getting the best performance from the MIXPAD, or from any mixer, for that matter. This is a simple procedure that ensures optimum input and output levels so that no unnecessary noise (caused by too low a signal) or overload distortion (ca[...]

24 Setting the Cor rect Gain Str ucture h. Once you’ve set the optimum level in step (g) above, continue playing the instrument and slowly raise the power amplifier volume until you reach the level you want to hear. i. Repeat step (g) above for each instrument connected to the MIXPAD channel line inputs. j. The procedure for setting optimum micro[...]

25 Setting the Cor rect Gain Str ucture l. The gain structure is now correctly set—you’ve optimized the level of all signals coming into and out of the MIXPAD, and the end result will be minimum noise and distortion and maximum clean sound. You’ll now find that the majority of your mixes can be accomplished with most channel Level controls at[...]

26 Grounding T echniques Hum and buzz are the biggest enemies you face when interconnecting a large number of different pieces of equipment to a central audio mixer. This is because each piece of equipment may operate at a marginally different voltage (this difference is called potential ) and, when two devices at slightly different potential are p[...]

27 Grounding T echniques We also recommend that you use balanced audio cabling and connectors wherever possible. The MIXPAD provides electronically balanced inputs for mono line channel inputs and for its main outputs. The wiring diagram in the “Connecting The MIXPAD” section of this manual (on page 19) shows how 1/4" TRS (Tip/Ring/Sleeve)[...]

28 Using P an/Balance The final Main output of the MIXPAD is stereo—that is, there are two discrete output jacks, labeled “left” and “right,” which will normally be routed to a stereo power amplifier and two discrete speakers.* Because of this, you will usually be working with a stereo field that ranges from hard left to hard right. The P[...]

29 Using P an/Balance In the MIXPAD 4 stereo channel (channels 3/4) and in MIXPAD 12 and MIXPAD 9 stereo channels (channels 7/8, 9/10, and 11/12 in the MIXPAD 12; channels 4/5, 6/7, and 8/9 in the MIXPAD 9) where both inputs are connected, the upper input signal is automatically panned hard left and the lower input signal is automatically panned ha[...]

30 One of the most exciting aspects of using a mixer such as the MIXPAD is the ability to shape a sound, using a process called equalization . But there are few areas of sound engineering more misunderstood than equalization, and, just as good EQ can really help a sound, bad EQ can really hurt it, so read on... Every naturally occurring sound consi[...]

31 Using Equalization In most instances, the best way to approach equalization is to think in terms of which frequency areas you need to attenuate, as opposed to which ones you need to boost (boosting a frequency area also has the effect of boosting the overall signal; too much EQ boost can actually cause overload—with the accompanying Left/Right[...]

32 Using Aux Sends and Retur ns The purpose of Auxiliary sends are to allow you to combine the signal from multiple channels and send the resulting mix to external devices such as effects processors. The MIXPAD 12 and MIXPAD 9 provide two such sends, while the MIXPAD 4 provides one. When a channel’s Aux send knob is at its “0” position, the s[...]

33 Using Aux Sends and Retur ns outboard devices (via Aux sends). In practice, you’ll probably want to use the Aux returns to bring in signal from connected effects processors. If the effects processors have stereo outputs, they should be connected to both the left and right Auxiliary return inputs so that their stereo integrity is retained. If t[...]

34 Appendix A: Operating the MIXP AD 12/9 off Batter y P ow er The MIXPAD 12 and MIXPAD 9 can optionally be battery powered. This requires the use of two 12 Volt rechargeable Lead-Acid (Gelcell) batteries, connected to the rear panel AC connector, wired as shown in the illustration below. These batteries will provide the necessary bi-polar voltages[...]

35 Appendix A: Operating the MIXP AD 12/9 off Batter y P ow er The current draw of the two models (without phantom power) are: MIXPAD9: 125mA (.125A) MIXPAD12: 160mA (.160A) Typical usage times for the two models: MIXPAD9 10 hours MIXPAD12 8 hours If you are using dynamic microphones, no phantom power is necessary. To power a condenser microphone, [...]

36 MIXP AD 12 / 9 Specifications Normal Limit Frequency Response (Trim @ Min, unity gain ± 3 dB) Mic to Main 5 Hz - 65 kHz 10 Hz - 50 kHz Line to Main 5 Hz - 65 kHz Aux Return to Main 5 Hz - 75 kHz Line to Aux Send 1/2 5 Hz - 75 kHz T.H.D. (Trim @ Min, +4dBu output, unity gain, 1 kHz w/30 Hz LPF) Mic/Line to Main (Mono Ch) 0.002% 0.01% Line to Mai[...]

37 MIXP AD 4 Specifications Normal Limit Frequency Response (Trim @ Min, unity gain ± 3 dB) Mic to Main 5 Hz - 54 kHz 10 Hz - 50 kHz Line to Main 5 Hz - 54 kHz Aux Return to Main 5 Hz - 98 kHz Line to Aux Send 5 Hz - 57 kHz T.H.D. (Trim @ Min, +4dBu output, unity gain, 1 kHz w/30 Hz LPF) Mic/Line to Main (Mono Ch) 0.02% 0.05% Line to Main (Stereo [...]

Notes[...]