MIXER / MICROPHONE PREAMPLIFIER REFERENCE MANUAL 2002
Important Safety Instructions
Important Safety Instructions Important Safety Instructions (English) Safety symbols used in this product This symbol alerts the user that there are important operating and maintenance instructions in the literature accompanying this unit. This symbol warns the user of uninsulated voltage within the unit that can cause dangerous electric shocks. This symbol warns the user that output connectors contain voltages that can cause dangerous electrical shock.
Important Safety Instructions 12. Use only with a cart, stand, bracket, or table designed for use with professional audio or music equipment. In any installation, make sure that injury or damage will not result from cables pulling on the apparatus and its mounting. If a cart is used, use caution when moving the cart/apparatus combination to avoid injury from tip-over. 13. Unplug this apparatus during lightning storms or when unused for long periods of time. 14.
Important Safety Instructions Instructions de Sécurité Importantes (French) Symboles utilisés dans ce produit Ce symbole alèrte l’utilisateur qu’il existe des instructions de fonctionnement et de maintenance dans la documentation jointe avec ce produit. Ce symbole avertit l’utilisateur de la présence d’une tension non isolée à l’intérieur de l’appareil pouvant engendrer des chocs électriques.
Important Safety Instructions Suite de la page suivante 12. N’utilisez qu’avec un stand, ou table conçus pour l’utilisation d’audio professionnel ou instruments de musique. Dans toute installation, veillez de ne rien endommager à cause de câbles qui tirent sur des appareils et leur support. 13. Débranchez l’appareil lors d’un orage ou lorsqu’il n’est pas utilisé pendant longtemps. 14. Faites réparer par un personnel qualifié.
Important Safety Instructions Lesen Sie bitte die folgende Sicherheitshinweise (German) Sicherheit Symbole verwendet in diesem Produkt Dieses Symbol alarmiert den Benutzer, daß es wichtige Funktionieren und Wartung Anweisungen in der Literatur gibt, die diese Maßeinheit begleitet. Dieses Symbol warnt den Benutzer der nicht isolierten Spannung innerhalb der Maßeinheit, die gefährliche elektrische Schläge verursachen kann.
Important Safety Instructions Fortsetzung auf nächster Seite 12. Verwenden Sie ausschließlich Wagen, Ständer, oder Tische, die speziell für professionelle Audio- und Musikinstrumente geeignet sind. Achten Sie immer darauf, daß die jeweiligen Geräte sicher installiert sind, um Schäden und Verletzungen zu vermeiden. Wenn Sie einen Rollwagen benutzen, achten Sie darauf, das dieser nicht umkippt, um Verletzungen auszuschließen. 13.
Important Safety Instructions CE Declaration Of Conformity See our website at: http://www.alesis.com FCC Compliance Statement This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference and (2) this device must accept any interference received, including interference that may cause undesired operation.
Power In Power Switch Aux Send 2 (Post Fader) Aux Send 1 (Pre Fader) Low Frequency EQ High Frequency EQ Tape Monitor In Phantom Power Switch 120 50-60 5 HZ 2 3W MAX REAR PANEL Monitor Out Channel Fader Line In Aux Sends Main Out Stereo Aux Return Main Out Channel Pan/Balance FRONT PANEL Gain Channel Insert Headphone Jack Master Level Microphone In Master Fader Phantom Power Indicator Monitor Select Switch Phones/Monitor Level Stereo Aux Return Level
Introduction TABLE OF CONTENTS AUX System: Effects Send/Receive............................................................30 How to Set Aux Send and Return Levels .......................................30 Using the meter..............................................................................................32 Avoiding noise................................................................................................33 System noise (ground loops, hum, induced noise).......................
Introduction TABLE OF CONTENTS AUX System: Effects Send/Receive............................................................30 How to Set Aux Send and Return Levels .......................................30 Using the meter..............................................................................................32 Avoiding noise................................................................................................33 System noise (ground loops, hum, induced noise).......................
Introduction INTRODUCTION Grounding Instructions The Alesis Multimix 12R Microphone Preamplifier/Mixer The Alesis Multimix 12R is a high-quality, rack-mountable 12-input, stereo output audio mixer. It is designed to handle eight microphones, two stereo line inputs, and to route signal to and from external effect processing devices. As a basic, easy-to-understand mixer, it can be used in a wide variety of applications from sound reinforcement to multitrack recording.
Introduction INTRODUCTION Grounding Instructions The Alesis Multimix 12R Microphone Preamplifier/Mixer The Alesis Multimix 12R is a high-quality, rack-mountable 12-input, stereo output audio mixer. It is designed to handle eight microphones, two stereo line inputs, and to route signal to and from external effect processing devices. As a basic, easy-to-understand mixer, it can be used in a wide variety of applications from sound reinforcement to multitrack recording.
Installation INSTALLATION Use clean power The Multimix 12R's internal power supply is designed to filter out most AC line noise. However, it is still good practice to plug your sound equipment into an AC circuit that is not shared with lighting dimmers, refrigerators, air conditioning units, or other appliances that may induce noise into the power system. Unpacking The Multimix 12R box should contain: 1. The mixer itself 2. A packet of literature along with this manual 3.
Installation INSTALLATION Use clean power The Multimix 12R's internal power supply is designed to filter out most AC line noise. However, it is still good practice to plug your sound equipment into an AC circuit that is not shared with lighting dimmers, refrigerators, air conditioning units, or other appliances that may induce noise into the power system. Unpacking The Multimix 12R box should contain: 1. The mixer itself 2. A packet of literature along with this manual 3.
Connections Connections CONNECTIONS Microphone Inputs The Alesis Multimix 12R features eight studio-grade, low-noise hybrid microphone preamplifiers. These [MIC] jacks are designed to work with almost any low-impedance microphone using standard 3conductor XLR connectors. The [MIC] jacks also feature 48 volt phantom power, which may be turned on and off by the [PHANTOM] switch on the back panel, for condenser microphones which require external powering.
Connections Connections CONNECTIONS Microphone Inputs The Alesis Multimix 12R features eight studio-grade, low-noise hybrid microphone preamplifiers. These [MIC] jacks are designed to work with almost any low-impedance microphone using standard 3conductor XLR connectors. The [MIC] jacks also feature 48 volt phantom power, which may be turned on and off by the [PHANTOM] switch on the back panel, for condenser microphones which require external powering.
Connections Phantom power Certain types of microphones (called condenser microphones) require a DC power supply from the mixer. “Phantom power” sends 48 volts of DC through the microphone cable. If any of your microphones need phantom power, turn on the [PHANTOM POWER] switch on the Multimix 12R’s back panel to connect all the XLR MIC IN jacks to the Multimix 12R’s internal 48 volt phantom power source.
Connections Phantom power Certain types of microphones (called condenser microphones) require a DC power supply from the mixer. “Phantom power” sends 48 volts of DC through the microphone cable. If any of your microphones need phantom power, turn on the [PHANTOM POWER] switch on the Multimix 12R’s back panel to connect all the XLR MIC IN jacks to the Multimix 12R’s internal 48 volt phantom power source.
Connections Balanced +4 dBu line level sources: Professional recording and processing equipment typically provides a balanced, 3-conductor signal output that is a higher voltage (1.24 volts nominal level) than most synthesizers and stereo equipment. The Multimix 12R’s [LINE IN] jacks are designed to handle these balanced inputs.
Connections Balanced +4 dBu line level sources: Professional recording and processing equipment typically provides a balanced, 3-conductor signal output that is a higher voltage (1.24 volts nominal level) than most synthesizers and stereo equipment. The Multimix 12R’s [LINE IN] jacks are designed to handle these balanced inputs.
Connections Phonograph turntables If you're using a record turntable, you may not plug it directly into the line inputs of the Multimix 12R (well, you can, but it will sound very thin and noisy). Obtain a phono preamp from your dealer or an electronics specialty store. Connections How to connect effect devices and signal processors Alesis and other companies make many different types of signal processors which may be connected to the Multimix 12R mixer.
Connections Phonograph turntables If you're using a record turntable, you may not plug it directly into the line inputs of the Multimix 12R (well, you can, but it will sound very thin and noisy). Obtain a phono preamp from your dealer or an electronics specialty store. Connections How to connect effect devices and signal processors Alesis and other companies make many different types of signal processors which may be connected to the Multimix 12R mixer.
Connections Connections You don’t need to connect anything to the other input of the effect, because most effect units use the stereo inputs only to provide a path for the “dry” stereo signal when the effect is connected directly between an instrument and an amplifier. In mixing applications such as with the Multimix 12R, you will set the effect’s wet/dry balance all the way to “wet” (effects only, no direct signal). The effect device will generate an artificial stereo output from the signal input.
Connections Connections You don’t need to connect anything to the other input of the effect, because most effect units use the stereo inputs only to provide a path for the “dry” stereo signal when the effect is connected directly between an instrument and an amplifier. In mixing applications such as with the Multimix 12R, you will set the effect’s wet/dry balance all the way to “wet” (effects only, no direct signal). The effect device will generate an artificial stereo output from the signal input.
Connections providing a direct output. Or, put the recorder into INPUT mode and insert the plug all the way, connecting the input and output of each track of the recorder into each channel path of the mixer. This will allow playback monitoring of the recorder. See the Applications chapter for more information. For more information on using the AUX and INSERT systems, see the “Operating Instructions” chapter of this manual.
Connections providing a direct output. Or, put the recorder into INPUT mode and insert the plug all the way, connecting the input and output of each track of the recorder into each channel path of the mixer. This will allow playback monitoring of the recorder. See the Applications chapter for more information. For more information on using the AUX and INSERT systems, see the “Operating Instructions” chapter of this manual.
Connections Connections To another mixer To an ADAT multitrack recorder The main or monitor outputs of the Multimix 12R may be connected to a larger mixing console. Consult the manual for the other mixer for more information. If the mixer has "SUB IN" jacks, connect to those. Alternatively, you may simply connect the MAIN OUT or MONITOR OUT jacks of the Multimix 12R to two line-level inputs on the other mixer. If you do, check to see what level those inputs are designed for.
Connections Connections To another mixer To an ADAT multitrack recorder The main or monitor outputs of the Multimix 12R may be connected to a larger mixing console. Consult the manual for the other mixer for more information. If the mixer has "SUB IN" jacks, connect to those. Alternatively, you may simply connect the MAIN OUT or MONITOR OUT jacks of the Multimix 12R to two line-level inputs on the other mixer. If you do, check to see what level those inputs are designed for.
Connections 2. Connect the stereo/TRS end to the INSERT jack of channel 1 of the Multimix 12R. 3. Connect the mono plug from the tip connector to the input of the ADAT. NOTE: the ADAT’s tracks are arranged from left to right on the back panel, and the mixer’s channels are from right to left, so the wires will have to cross over. If you're not sure which mono plug is from the tip and which is from the ring, check to see if the cable box has that information.
Connections 2. Connect the stereo/TRS end to the INSERT jack of channel 1 of the Multimix 12R. 3. Connect the mono plug from the tip connector to the input of the ADAT. NOTE: the ADAT’s tracks are arranged from left to right on the back panel, and the mixer’s channels are from right to left, so the wires will have to cross over. If you're not sure which mono plug is from the tip and which is from the ring, check to see if the cable box has that information.
Connections Phones The [PHONES] jack on the front panel is designed for most stereo headphones. The internal headphone amplifier outputs the maximum power allowed by safety standards. The impedance and efficiency of the headphones will determine the maximum volume available. Eightohm headphones may be louder at a given setting than 150-ohm or 600-ohm headphones; however, there should be enough gain to drive any dynamic headphone to reasonable levels, if the mixer is being run properly.
Connections Phones The [PHONES] jack on the front panel is designed for most stereo headphones. The internal headphone amplifier outputs the maximum power allowed by safety standards. The impedance and efficiency of the headphones will determine the maximum volume available. Eightohm headphones may be louder at a given setting than 150-ohm or 600-ohm headphones; however, there should be enough gain to drive any dynamic headphone to reasonable levels, if the mixer is being run properly.
Operating Instructions OPERATING Operating Instructions Setting input trim levels INSTRUCTIONS ✪ Proper setting of the [TRIM] controls is crucial to low-noise, distortionfree operation. If the trim is set too high, there will be distortion even if the channel faders are low. If the trim is set too low and the channel faders are raised to get the signal loud enough, you will be amplifying the noise of the mixer.
Operating Instructions OPERATING Operating Instructions Setting input trim levels INSTRUCTIONS ✪ Proper setting of the [TRIM] controls is crucial to low-noise, distortionfree operation. If the trim is set too high, there will be distortion even if the channel faders are low. If the trim is set too low and the channel faders are raised to get the signal loud enough, you will be amplifying the noise of the mixer.
Operating Instructions Metering/Unity Gain method Operating Instructions Typical Fader and Control Levels This method gives you more headroom than the peak method, while maintaining a low noise floor which will be well below the noise of most PA or live recording environments. 2. Set the CHANNEL FADER to 0 (about 2/3 up). Set all other channel faders to minimum (off).
Operating Instructions Metering/Unity Gain method Operating Instructions Typical Fader and Control Levels This method gives you more headroom than the peak method, while maintaining a low noise floor which will be well below the noise of most PA or live recording environments. 2. Set the CHANNEL FADER to 0 (about 2/3 up). Set all other channel faders to minimum (off).
Operating Instructions Proper gain staging of other equipment Operating Instructions AUX System: The total noise performance of your system depends on proper gain control of all the elements. A "noisy mixer" is usually a quiet mixer in a system whose gain structure is incorrect. As a good starting point, set most volume level controls of other equipment at 3/4 or 75% of full. This will decrease the possibility of overload distortion and keep the amount of background noise to a minimum.
Operating Instructions Proper gain staging of other equipment Operating Instructions AUX System: The total noise performance of your system depends on proper gain control of all the elements. A "noisy mixer" is usually a quiet mixer in a system whose gain structure is incorrect. As a good starting point, set most volume level controls of other equipment at 3/4 or 75% of full. This will decrease the possibility of overload distortion and keep the amount of background noise to a minimum.
Operating Instructions By having the correct level at every point in the send/return chain, you avoid distortion by overloading and avoid noise. The most common mistake with effect units is to have too low a level at the send or input, then crank up the output of the processor or the Aux return to get the effects level desired. This amplifies the noise and wastes headroom.
Operating Instructions By having the correct level at every point in the send/return chain, you avoid distortion by overloading and avoid noise. The most common mistake with effect units is to have too low a level at the send or input, then crank up the output of the processor or the Aux return to get the effects level desired. This amplifies the noise and wastes headroom.
Operating Instructions Avoiding noise If the Multimix 12R is being run as suggested above, the noise of the mixer itself will not be a significant factor in the noise level of your system, since the Multimix 12R generates much less noise than the typical source does. Noise is present in every system, analog or digital; as operator it's your job to run the system (and particularly the mixer) so that the noise isn't amplified unnecessarily. But the Multimix 12R cannot remove noise that is already there.
Operating Instructions Avoiding noise If the Multimix 12R is being run as suggested above, the noise of the mixer itself will not be a significant factor in the noise level of your system, since the Multimix 12R generates much less noise than the typical source does. Noise is present in every system, analog or digital; as operator it's your job to run the system (and particularly the mixer) so that the noise isn't amplified unnecessarily. But the Multimix 12R cannot remove noise that is already there.
Operating Instructions rack from being conducted back to the mixer. Even though the mixerto-amp connection is balanced, any unbalanced sources or effects plugged into the mixer may exhibit a hum when the amp's ground is carried back to the mixer.
Operating Instructions rack from being conducted back to the mixer. Even though the mixerto-amp connection is balanced, any unbalanced sources or effects plugged into the mixer may exhibit a hum when the amp's ground is carried back to the mixer.
Applications APPLICATIONS Applications Mixdown You may leave the ADAT connected to the INSERT jacks for mixdown; there's no need to repatch to the LINE IN jacks. Multitrack recording See the "Connections" chapter for information on how to connect the Multimix 12R to an ADAT or other multitrack recorder. Make the connections according to the procedure in the "Connections" chapter. In the most common setup, the ADAT is patched into the INSERT points of each channel.
Applications APPLICATIONS Applications Mixdown You may leave the ADAT connected to the INSERT jacks for mixdown; there's no need to repatch to the LINE IN jacks. Multitrack recording See the "Connections" chapter for information on how to connect the Multimix 12R to an ADAT or other multitrack recorder. Make the connections according to the procedure in the "Connections" chapter. In the most common setup, the ADAT is patched into the INSERT points of each channel.
Applications Using the HIGH and LOW EQ controls Monitoring AUX 1 in the PHONES jack The Multimix 12R provides standard shelving EQ controls on each channel. The HIGH knob range is +/- 15 dB with a shelving frequency of 12 kHz. "Shelving" means that all frequencies above 12 kHz will be boost or cut by the same amount , and frequency response between 1 kHz and 12 kHz will gradually rise or fall to the shelving point. The LOW knob range is +/- 15 dB at a shelving frequency of 80 Hz.
Applications Using the HIGH and LOW EQ controls Monitoring AUX 1 in the PHONES jack The Multimix 12R provides standard shelving EQ controls on each channel. The HIGH knob range is +/- 15 dB with a shelving frequency of 12 kHz. "Shelving" means that all frequencies above 12 kHz will be boost or cut by the same amount , and frequency response between 1 kHz and 12 kHz will gradually rise or fall to the shelving point. The LOW knob range is +/- 15 dB at a shelving frequency of 80 Hz.
Specifications TROUBLESHOOTING Hum or noise from output. Troubleshooting Index If you experience problems while operating the Multimix 12R, please use the following table to locate possible causes and solutions before contacting Alesis Product Support or your dealer for assistance. Symptom Cause The Power LED does No power. not light when the unit is powered on. Sound is distorted, red Input level is too “PEAK” LED is lit. high. Sound is excessively noisy, faders must be raised to full to hear.
Specifications TROUBLESHOOTING Hum or noise from output. Troubleshooting Index If you experience problems while operating the Multimix 12R, please use the following table to locate possible causes and solutions before contacting Alesis Product Support or your dealer for assistance. Symptom Cause The Power LED does No power. not light when the unit is powered on. Sound is distorted, red Input level is too “PEAK” LED is lit. high. Sound is excessively noisy, faders must be raised to full to hear.
Specifications Maintenance/Service Exterior cleaning Disconnect the AC cord, then use a damp cloth to clean the mixer’s metal and plastic surfaces. For heavy dirt, use a non-abrasive household cleaner such as Formula 409 or Fantastik. DO NOT SPRAY THE CLEANER DIRECTLY ONTO THE FRONT OF THE UNIT AS IT MAY DESTROY THE LUBRICANTS USED IN THE SWITCHES AND CONTROLS! Spray onto a cloth, then use cloth to clean the unit. Never spray any kind of cleaner into the faders, even if it claims to be safe for such use.
Specifications SPECIFICATIONS Levels MIC IN All measurements taken with an Audio Precision System One. All noise measurements taken with trim at minimum and faders at unity gain with 22 Hz to 22 kHz bandwidth unless otherwise specified. All In & Out measurements made on balanced +4 dBu connectors. (+4 dBu into a line input with faders at unity and the meter reading “0” will yield +4 dBu into a balanced load or -2 dBu into an unbalanced load.
Specifications SPECIFICATIONS Levels MIC IN All measurements taken with an Audio Precision System One. All noise measurements taken with trim at minimum and faders at unity gain with 22 Hz to 22 kHz bandwidth unless otherwise specified. All In & Out measurements made on balanced +4 dBu connectors. (+4 dBu into a line input with faders at unity and the meter reading “0” will yield +4 dBu into a balanced load or -2 dBu into an unbalanced load.
Specifications Noise performance (typical) Measured at MAIN OUT +4 dBu jacks, unbalanced load, 22 Hz to 22 kHz, all channels panned to center. MIC IN to INSERT OUT: -128.
Specifications Noise performance (typical) Measured at MAIN OUT +4 dBu jacks, unbalanced load, 22 Hz to 22 kHz, all channels panned to center. MIC IN to INSERT OUT: -128.
Specifications B LOCK Multimix 12R Reference Manual Specifications Level diagram DIAGRAM 49
Specifications B LOCK Multimix 12R Reference Manual Specifications Level diagram DIAGRAM 49
Index INDEX ADAT, 18, 22, 34, 39 amplifier, 20, 31 Aux 1, 17, 20 AUX 2, 16, 32 AUX SEND, 16, 20 balanced, 12, 20 cable, 9 clipping, 13 compressor, 17 direct output using INSERT jack, 18 distortion, 28, 31 effect, 16 EQ, 31 Fader, 30 feedback, 20, 21 gain, 30 ground loop, 35 isolating from rack, 8 grounding, 6, 7 guitars, 12 Headphone, 20, 25 headroom, 13, 34, 48 HIGH, 41 Impedance, 10, 48 INSERT cables, 22 INSERT jack, 17, 24 PHONES, 25 PHONES/MONITOR, 14, 34 phonograph, 15 post-fader, 32 pre-fader, 17
Warranty / Contact Alesis Limited Warranty ALESIS CORPORATION ("ALESIS") warrants this product to be free of defects in material and workmanship for a period of one (1) year for parts and for a period of one (1) year for labor from the date of original retail purchase. This warranty is enforceable only by the original retail purchaser and cannot be transferred or assigned. For the most effective service, the purchaser should register the purchase on the ALESIS website at http://www.alesis.
Alesis Contact Information Alesis Distribution, LLC Los Angeles, CA USA E-mail: Website: support@alesis.com http://www.alesis.com Alesis Multimix 12R Reference Manual Revision 1.0 by Brooks Bruner Copyright 2002, Alesis Distribution, LLC. All rights reserved Reproduction in whole or in part is prohibited. “Multimix 12R” is a trademark of Alesis Distribution, LLC. Specifications subject to change without notice.
