MIXER SAMSON MPL 1204 ®
Introduction 3 MPL 1204 Features 3 Guided Tour 5 Overview 5 Channels 6 Main Section 8 Rear Panel 11 Connecting The MPL 1204 - General Suggestions 13 Setting Up and Using the MPL 1204 15 Setting the Correct Gain Structure 16 Grounding Techniques 18 Busing, Submixing, and Channel Muting 19 Using Pan 20 Using Equalization 21 Using Aux Sends and Returns 22 Using Inserts 23 PFL/AFL Soloing 24 Applications Notes 25 Using The MPL 1204 As A Recording Mixer 25 Using The MPL 1204 As A Main Live Mixer 26 Using The
Introduction / MPL 1204 Features Congratulations on purchasing the Samson MPL 1204 four-bus microphone/line mixer! The MPL 1204 is optimized for use in both live performance and recording applications, and it can be used wherever there are a number of microphone or line-level sources that need to mixed down to two or four outputs.
MPL 1204 Features • Electronically balanced XLR Main stereo outputs as well as an independent electronically balanced stereo Control Room output (with dedicated level control) for connection to a power amplifier and studio monitors. • A phantom power switch enables you to use the MPL 1204 with high-quality condenser microphones. When turned on, 48 volts of phantom power is provided to the mic connectors of all twelve input channels.
Guided Tour - Overview The following illustration shows an overview of the front panel of the MPL 1204: LIN LIN +4 -50 -30 HIGH 0 +4 E +4 E MID MID 0 +12 -12 LOW +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 MID 0 +12 -12 LOW 0 +15 -15 +12 -12 LOW
Guided Tour - Channels CH 1 +4 E M I C LIN TRIM 1 +4 -50 -30 +24 HIGH 0 +15 -15 MID 0 2 +12 -12 LOW 0 +15 -15 AUX 1 PRE 0 ∞ +10 AUX 2 POST 0 ∞ +10 4 SOLO ON 3 OFF 5 MUTE 3/4 6 1: Trim (black) - This knob determines the input level of the connected signal. Continuously adjustable from +4 dB to -50 dB (for mic inputs) or +24 to -30 dB (for line inputs), the input signal is boosted when the trim is turned clockwise and attenuated when turned counterclockwise.
Guided Tour - Channels 7: Level (white) - This knob (purposely made a little bigger than the others so you can find it easily in low-light situations) controls the volume of the channel input. In practice, you will use the Level controls to continuously adjust the loudnesses of the various signals being blended together by the MPL 1204. The “0” (2 o’clock) position of the knob indicates unity gain (no level attenuation or boost).
Guided Tour - Main Section AUX RETURNS STEREO SAMSON 0 MPL 1204 MIC MIXER ∞ +10 AUX RET.1/2 MUTE 3/4 -20 -15 -9 -6 -3 0 +2 +4 +6 +8 -20 -15 -9 -6 -3 0 +2 +4 +6 +8 LEFT RIGHT 1 2 R L BALANCE PHANTOM AFL PFL PHANTOM SOLO METER PFL AFL 0 POWER TAPE 1-2 3-4 11/12 ∞ +10 AUX RET.
Guided Tour - Main Section 3: Stereo Auxiliary Return Balance (brown) - These knobs determine the relative levels of the left and right input signals connected to the MPL 1204’s two stereo Auxiliary returns. When the knob is placed at its center (detented) position, both left and right input signals for that Aux return are at equal strength.
Guided Tour - Main Section certain that one or more connected mics require 48 volts phantom power, leave this switch off (its out position). 10: Meter switch - When out, the ten-segment MPL 1204 meter (see #6 on the previous page) shows the continuous output level of Bus 1-2; when pressed in, the meter shows the continuous output level of Bus 3-4.
Guided Tour - Rear Panel 7 4 9 MPL 1204 12 CHANNEL MIC MIXER TRS STEREO INPUT POWER 2 TIP = LEFT RING = RIGHT SLEEVE = COM SAMSON 2 1 3 2 1 2 1 3 2 1 2 1 3 3 3 10 9 8 2 1 3 2 1 3 2 1 3 2 1 2 1 2 1 1 3 3 3 3 4 3 2 1 ON 1 TRS BALANCED TIP = HI RING = LO SLEEVE = COM OFF 12 11 AUX RETURNS STEREO INPUTS UNBALANCED 10KΩ +4dBu TAPE IN 3/4 1/2 UNBALANCED 10KΩ -10dBu TRS INSERT UNBALANCED TIP = RETURN RING = SEND SLEEVE = COM 10 9 11 10 9 LINE INPUTS BALAN
Guided Tour - Rear Panel 7: Aux Returns (1/2, 3/4) - These unbalanced 1/4" TRS inputs allow you to route signal from external devices such as effects processors to either of the two stereo Aux Returns. These jacks accept 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 Aux Sends and Returns” section on page 20 in this manual for more information.
Connecting The MPL 1204 - General Suggestions The actual connections you’ll make to and from the MPL 1204 will vary according to the environment you use it in and the particular equipment you have. In the “MPL 1204 Applications” sections at the rear of this manual, you’ll find some suggested setups. Here are a few basic rules concerning MPL 1204 connections that will apply in most situations: • In general, it’s best to make all connections with the MPL 1204 and any connected power amplifiers turned off.
Connecting The MPL 1204 - General Suggestions • NEVER connect a microphone and line level input to the same channel simultaneously—use one or the other. You can have some channels connected to microphones and others to line level signals (for example, you might want to plug mics into channels 1 - 4 and line level signals into the remaining channels)—just don’t have both kinds of inputs connected to the same channel.
Setting Up and Using The MPL 1204 Setting up your MPL 1204 is a simple procedure which takes only a few minutes: LEFT RIGHT 1. Remove all packing materials (save them in case of need for future service) and decide where the unit is to be physically placed—it can be mounted in any standard 19" rack, requiring four rack spaces, or used on a tabletop. 2.
Setting the Correct Gain Structure You’re now ready to establish the correct gain structure—the key to getting the best performance from the MPL 1204, 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 (caused by too high a signal) is created. Here’s a step-by-step description of how to do so: a.
Setting the Correct Gain Structure h. Once you’ve set the optimum level in step (g) above, continue playing the instrument and slowly raise the level of your power amplifier until you reach the desired listening level. Repeat step (g) above for each instrument connected to the MPL 1204 channel line inputs. i.
Grounding Techniques Hum and buzz are the biggest enemies you face when interconnecting a large number of different pieces of equipment to a central audio mixer.
Busing, Submixing and Channel Muting As we’ve seen, the MPL 1204 uses a system of four buses—pathways through which signal can be routed. The four MPL 1204 bus faders control the overall level of the signal being output through the four buses. When the “L/R” switches above each bus fader are pressed in, the signal from that bus is also routed to the Main and Control Room outputs.
Using Pan R L PAN The final Main output of the MPL 1204 is stereo—that is, there are two discrete Main output jacks (and two discrete Control Room output jacks), labeled “left” and “right,” which will normally be routed to two discrete speakers.* Because of this, you will usually be working with a stereo field that ranges from hard left to hard right. The MPL 1204 provides twelve monophonic input channels, each with its own dedicated Pan control.
Using Equalization One of the most exciting aspects of using a mixer such as the MPL 1204 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... HIGH Every naturally occurring sound consists of a broad range of pitches, or frequencies, combined together in a unique way.
Using Aux Sends and Returns AUX 1 ∞ AUX 2 ∞ PRE 0 +10 POST 0 +10 AUX RETURNS STEREO The MPL 1204’s two Auxiliary sends allow you to combine the signal from multiple channels and send the resulting mix to external devices such as effects processors. When an Aux send knob is at its 2 o’clock “0” position, the signal is routed with unity gain (that is, no boost or attenuation).
Using Inserts In addition to using Auxiliary sends and returns to access outboard devices, the MPL 1204 also provides channel inserts for each of its twelve input channels. These should be used when you want to affect just one input signal, as opposed to signal from several inputs—most often, this will be for dynamic processing purposes (such as outboard equalization, compression/limiting, or noise gating).
PFL/AFL Soloing SOLO PFL AFL SOLO ON OFF The MPL 1204 provides two options for soloing input signals in headphones connected to the front panel headphone jack—Pre Fade Listen (PFL) and After-Fade Listen (AFL). The Solo switch in the main section (#8 on page 7) allows you to choose between these two modes of operation. Although they may at first glance appear similar (and although both are non-mix-destructive), there is in fact a significant difference between the two.
Applications Here are four suggested applications for the MPL 1204; bear in mind that your particular circumstance may dictate changes in these suggested signal connections and routings. Application 1 - Using The MPL 1204 As A Recording Mixer The MPL 1204 is optimized for use as a recording mixer with multitrack digital or analog recorders. As shown in the illustration below, microphones and line level signals are connected to various channel inputs.
Applications Application 2 - Using The MPL 1204 As A Main Live Mixer Here, the MPL 1204’s Main output is connected to the input of a power amplifier, and, from there, to PA speakers. Microphones and line level signals are connected to various channel inputs, and a two-track tape deck is connected to the Tape/CD inputs.
Applications Application 3 - Using The MPL 1204 As A Keyboard Submixer Here, various keyboards and MIDI tone generators are connected to the channel line inputs of the MPL 1204. Signal processors are connected to Aux sends and returns and to channel inserts as required. The Main output can then be routed to a stereo input channel of a live performance or recording mixing console, with the performer having complete control over the blend of signals being provided to the sound engineer.
Applications Application 4 - Linking The MPL 1204 With Other Mixers The provision of four rear-panel Bus inserts makes it easy to link multiple MPL 1204s or to link the MPL 1204 with other mixers, without the need to use up channel line inputs. As shown in this illustration, simply connect the main output of another mixer to one or two MPL 1204 Bus inserts (use two for stereo linking).
AUX RETURN 3/4 +4dBU AUX RETURN 1/2 +4dBU INSERT (CH11-12) +4dBU LINE (CH11-12 -30dBU MIC(CH11-12) BALANCED -50dBU --- +4dBU INSERT (CH1-10) +4dBU LINE (CH1-10) -30dBU MIC(CH1-10) BALANCED -50dBU --- +4dBU TRIM H.A AUX RETURN 3/4 H.A H.A AUX RETURN 1/2 H.A H.A H.
Specifications Normal 1. Frequency Response (±3 dB) Mic in to Main out Mic in to Aux Send Aux return to Main out Tape in to Main out Limit DC ~ 65 kHz DC ~ 65 kHz DC ~ 160 kHz DC ~ 65 kHz 20 Hz - 50 kHz 20 Hz - 50 kHz 20 Hz - 50 kHz 20 Hz - 50 kHz 2. Total Harmonic Distortion (20 Hz to 20 kHz, with 30 kHz LPF) Mic in to Main out (Trim max) 0.06% < 0.1 % Line in to Main out (Trim min) 0.009% < 0.03 % Aux return to Main out 0.07% < 0.03 % 3.
Produced by On The Right Wavelength for Samson Technologies Corp. Copyright 1997, Samson Technologies Corp. Printed March 1997 Samson Technologies Corp. 575 Underhill Blvd. P.O.
