Compressor / Limiter / Expander

Reference Manual

CLX-440 Reference Manual

CLX-440 Manual

Contents

Contents....3

Welcome!....6 How to Use This Manual...7 Important Safety Instructions...8 CE Declaration of Conformity...10 Instructions to the User (FCC Notice)..14

Quick Start Guide....15

If you can't wait to get started:..15 Step 1: Hook it up to a mixer...15 Step 2: Try some compression..16 Step 3: Try some gating...17

Connections....19

Unpacking and Inspection...19 Installing in a Rack....19 Power....20 Connecting inputs and outputs..22 Connecting to the Channel Inserts of a mixing console:.22 Connecting to the Main Inserts of a mixing console:..23 Connecting to the inserts on an instrument amplifier:.24 Connecting to equipment with XLR inputs and outputs:.24 About Audio Cables...25 Dual Channel Operation..26
Basics of Compression....27
What is compression?....27 Description of Controls...28 Threshold....28 Ratio...29 Attack....29 Release....29 Detect....29 Knee...30 Compression Artifiacts...31 Pumping and Breathing..31 Clicking or "Zipper Noise"..31 Reduced Gain Structure..31
CLX-440 Manual Limiting....32 Limiter Threshold...32 Stereo Detection....33 Look Ahead Compression...33 Sidechain....34
Basics of Expansion....35
What is expansion?....35 Description of Controls...36 Threshold....36 Ratio...36 Knee...37 Attack....37 Hold...37 Release....38 Keyed Expansion...39

Applications....41

Compressor Applications...41 Vocal Limiting...41 Vocal Compression...42 Drums...42 Bass...43 Electric Guitar...43 Compressor Applications using the Sidechain..44 De-essing...44 Ducking...45 Expander Applications...46 Gating a Noisy Guitar Amp..46 Expanding Live Vocal Tracks..46 Expander Applications using the Key..47 Gated Reverb...47 Key Filtering for a Tom Mic gate..48 Staccato Gating a Synth Pad..49

Troubleshooting...51

Troubleshooting Index...51 Avoiding ground loop noise..52 Line Conditioners and Protectors..53 Care and Maintenance...54 Cleaning....54 Refer All Servicing to Alesis..54 Obtaining Repair Service..55 Specifications....57
CLX-440 Manual Audio Input...57 Sidechain/ Key Inputs...57 Direct Output...57 Audio Output...57 Audio Performance...57 Mechanical...58
Alesis Limited Warranty....59

Welcome!

Thank you for making the Alesis CLX-440 a part of your studio. Since 1984, we've been designing and building creative tools for the audio community. We believe in our products, because we've heard the results that creative people like you have achieved with them. One of Alesis' goals is to make highquality studio equipment available to everyone, and this Reference Manual is an important part of that. After all, there's no point in making equipment with all kinds of capabilities if no one explains how to use them. So, we try to write our manuals as carefully as we build our products. The goal of this manual is to get you the information you need as quickly as possible, with a minimum of hassle. We hope we've achieved that. If not, please drop us an email and give us your suggestions on how we could improve future editions of this manual. We hope your investment will bring you many years of creative enjoyment and help you achieve your goals. Sincerely, The people of Alesis Studio Electronics

How to Use This Manual

This manual is divided into the following sections describing the various functions and applications for the CLX-440. While it's a good idea to read through the entire manual once carefully, those having general knowledge about studio equipment should use the table of contents to look up specific functions. Chapter 1: Quick Start. If you're already familiar with recording, this will get you started using the CLX-440 right away. It's a short guide to the essential elements of connections and operation. Chapter 2: Connections. This section gives detailed instructions for connecting the CLX-440 to a variety of typical audio systems. Chapter 3: Basics of Compression. This section explains what a compressor does and explains the function of each of the controls. Chapter 4: Basics of Expansion. This chapter explains the other major feature of the CLX-440, expansion, and each of the front panel controls dedicated to this function. Chapter 5: Applications. Skip to this section for tips on using the CLX-440 with a variety of audio sources. Chapter 6: Troubleshooting. Refer to this chapter if you experience any problems while using the CLX-440. Helpful tips and advice are highlighted in a shaded box like this.
The names of specific controls or connectors on the CLX-440 are printed in a special font, i.e., the BYPASS button.
When something important appears in the manual, an icon (like the one on the left) will appear in the left margin. This symbol indicates that this information is vital when operating the CLX-440.
Important Safety Instructions
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.
Please follow these precautions when using this product:
1. Read these instructions. 2. 3. 4. 5. 6. Keep these instructions. Heed all warnings. Follow all instructions. Do not use this apparatus near water. Clean only with a damp cloth. Do not spray any liquid cleaner onto the faceplate, as this may damage the front panel controls or cause a dangerous condition. Install in accordance with the manufacturer's instructions. Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat. 9. Do not defeat the safety purpose of the polarized or groundingtype plug. A polarized plug has two blades with one wider than the other. A grounding-type plug has two blades and a third grounding prong. The wide blade or the third prong are provided for your safety. When the provided plug does not fit

Insert Send: To Compressor Input

Ring: Insert Return

Tip: Insert Send

Sleeve: Insert Ground

Insert Return: From Compressor Output
This cable splits the TRS insert jack into two unbalanced mono connectors. Usually, the tip is connected to the INPUT of the compressor and the ring is connected to the OUTPUT of the compressor. However, this may be reversed on some recording consoles. Check your mixers Reference Manual to be sure or just try it both ways this wont damage the CLX-400.
Channel Insert Compressor Out Compressor In
chapter 2 connections This example shows you how to connect the CLX-440 to one mono source. You can use this method to connect two mono or stereo sources to the CLX-440. You would need up to four insert cables to make these connections. Balanced I/O Some recording consoles have balanced sends and returns for each channel. If your recording console has these connections, use a balanced TRS cable to connect the insert send to the INPUT of the compressor, and another balanced TRS cable to connect the compressor OUTPUT to the insert return.
Connecting to the Main Inserts of a mixing console:
Unbalanced I/O In addition to channel inserts, most mixing consoles have main insert jacks near the main outputs. You can use insert cables to connect the CLX-440 to the main L/R bus the same way you connect it to a pair of channels. Simply connect one insert cable to the left main insert of the mixer, and connect the two mono jacks to the left INPUT and OUTPUT of the CLX-440. Use another insert cable to connect the right main insert to the right INPUT and OUTPUT of the CLX-440. Tip: Use both channels Since the CLX-440 has two stereo channels, A and B, you can connect two independent stereo sources. Try using channel A to compress the bass guitar, and channel B to compress the main output bus. Or use channel A on the drum room mics and channel B for the snare drum.
Balanced I/O Some recording consoles have balanced sends and returns for the main output bus. If your recording console has these connections, use a balanced TRS cable to connect the left main insert send to the left I N P U T of the compressor, and another balanced TRS cable to connect the compressors left OUTPUT to the left insert return. Repeat these steps for the right main insert. You can also simply connect the balanced main outputs of the mixer to the inputs of the CLX-440, then connect the outputs of

connections chapter 2 And most importantly, keep connectors clean. Every few months, unplug them and wipe off oxidation with a clean cloth soaked in alcohol or contact cleaner. Insert the plugs in the jacks a few times, to clean the internal jack contacts. Although Alesis does not endorse any specific product, chemicals such as Tweek and Cramolin, when applied to electrical connectors, are claimed to improve the electrical contact between connectors.
The CLX-440 is wired according to the modern standard of "Pin 2 (tip) = Hot". Some older equipment was wired with Pin 3 hot; check to make sure correct polarity is maintained throughout your system.

Dual Channel Operation

Remember that the CLX-440 is a dual-channel stereo compressor. That means that channels A and B can be used as two independent stereo compressors. It also means that audio from one channel does not affect the other unless you use the sidechain (discussed in Chapter 3). Remember to plug audio into the Left or Right input of the channel you are using.

Chapter 3

Basics of Compression
This section will explain how compression works, and explain the functions of the CLX-440s controls.

What is compression?

A compressor essentially turns down the volume of any audio which is louder that a set level. This level is called the compressor threshold level. If the input signal stays below the setting of the threshold level, nothing will happen. When the input signal is louder than the compressor threshold, this signal is reduced in volume. The amount of reduction is determined by the compression ratio. A ratio of 2:1 means that for every 2 dB above the threshold level, the output will only get 1 dB louder. If the ratio is 8:1, the input signal will have to be 8 dB louder than the threshold to get 1 dB louder after compression. If the ratio is infinity to one (:1), this is referred to as limiting. Limiting means that the output will never get any higher than the threshold setting. Compression is used for: Keeping recording levels under control so that the recorder doesnt distort Keeping vocal or instrument performances in the same general level range so that theyre easier to mix with other instruments Compressing the mix output so that it doesnt exceed a certain technical maximum in broadcast or post production In live sound reinforcement, keeping the volumes under control so that they dont distort Making tracks sound "punchy"
Compressors can make your recorded tracks sound polished and professional. Chapter 5 will give specific example settings for various instruments.

Clicking or "Zipper Noise"
You may also hear clicking if you are doing a lot of compression with a very short attack or release time. If this is the case, try raising the attack or release time to stop the clicking.

Reduced Gain Structure

As you compress the signal more and more, the output level will be lower as a result. Use the OUTPUT knob to make up for the gain youve lost during compression. By watching the INPUT, OUTPUT and GAIN REDUCTION meters, you should be able to set the OUTPUT knob so that the input and output levels roughly match.

Limiting

Limiting is compression with a very high Ratio setting (10:1 or more). It is typically used for stopping peaks in the signal from distorting the rest of the chain without affecting the dynamic range of the signal. When you are using the CLX-440 as a limiter, the threshold should be set high enough so that it only effects the highest momentary peaks in the signal. There are two ways to use the CLX-440 as a limiter. The first is to set the compression RATIO control to 10:1 or higher (about 3 oclock). If you set the ratio to :1, the output signal will not go any higher than the threshold level.

Limiter Threshold

The other way to use the CLX-440 as a limiter is to use the dedicated limiter on the output. In addition to the compression and expansion circuits in the CLX-440, there is a dedicated limiter on the output. This limiter has only one setting: THRESHOLD. You can use this limiter in addition to the compressor. An example would be compressing a vocal performance at 4:1 to keep the dynamic range narrow while setting the limiter threshold to 3 dBfs to avoid distorting the recorder. If you need more control over the limiter, such as adjustable attack and release time, knee or detection, you should use the compression circuit as a limiter with a high ratio setting.

Stereo Detection

The CLX-440 takes the greater of both left and right sides of each channel before they are detected for compression or expansion. The reason for this is so the two sides of a stereo signal are not gain reduced differently. For example, if a guitar was panned to the right and went above the threshold level, and the left and right sides were not linked, only the right side would be gain reduced. In this case, the stereo image of anything panned center would shift to the left. To keep this from happening, the left and right detectors of a channel are always simultaneously checked. This is why you should use the left and right sides of a channel - rather that sending the left side of a signal to compressor channel A and the right side to channel B. In addition to wasting a compressor channel, you may cause the center imaging of your signal to wander.

Look Ahead Compression

The CLX-440 has a feature called LOOK AHEAD. This feature uses an audio delay to provide immediate compression. When a signal is input, the detector takes 0.02ms to determine its level and apply gain reduction at its fastest attack setting. In some applications, this allows a quick transient to be passed through the compressor before gain reduction is applied. Look Ahead Compression delays the signal by 2ms to give the detector time to apply compression. In most applications, this delay is not noticeable and the gain reduction will appear to be instantaneous. This feature is especially useful as a mix compressor, making sure that the stereo mix does not overload the mixdown recorder.

Sidechain

There are a pair of balanced jacks on the rear panel which can alter the way the compressor functions, Direct Out and Sidechain. The DIRECT OUT jack sums the signal from the input and sends it out without compression. Using this jack by itself does not affect the rest of the compressor circuit. The input signal is sent both to the direct out and the rest of the compression circuit. This jack is designed for use with the sidechain, but may also be useful for recording a performance both with and without compression. The SIDECHAIN input is connected to the detector. It is provided so that a modified version of the signal, or a different signal altogether, can affect the compression. The most common uses for the direct out and sidechain features are de-essing and ducking.
Direct Out Sidechain In Detection

Output

In the diagram above, you can see that the input signal goes both to the DCA (Digitally Controlled Amplifier) and the Direct Out. The Sidechain In and Input signal both feed into the detector. The Front Panel SIDECHAIN button determines which of these sources is sent to the detector, which controls the DCA. For more information on De-essing and Ducking, see "Compressor Applications using the Sidechain".

Chapter 5,

Chapter 4

Basics of Expansion

This section explains the expansion features of the CLX-440.

What is expansion?

An expander reduces gain the opposite way a compressor does. When the input signal level is below the threshold level, that audio will be attenuated according to the ratio setting. If the expansion ratio is 4:1, then audio that is 1dB under the threshold will be attenuated so that it is 4dB below the threshold. When the ratio is set to :1, this is referred to as gating. This is the most common use for an expander. In many recordings, there is an unacceptable amount of noise in the recording. This may be tape hiss, AC hum, chair squeaks, or anything else which is distracting to the signal. A noise gate can be used to silence the source when it is not actually playing. The threshold should be set so that it opens when the instrument plays then closes when it is finished playing. Gating is most effective on signals with a quick attack and a strong signal level. Some examples are electric guitar, snare drum, piano or voice. Some instruments that may be more challenging to effectively gate would be strings, flute, synth pads and cymbal rolls.

Noise Gate

Silence
basics of expansion chapter 4
There are six knobs on the bottom row of each channel of the CLX-440, labeled EXPANDER. Their function is as follows:
The THRESHOLD knob sets the level where expansion will begin. As long as the input signal level is above the Threshold level, the CLX-440 will do nothing to the signal. Once the input signal crosses below the Threshold, the CLX-440 will begin expanding at an intensity set by the RATIO control. For example, if the threshold level is set to 30dBfs, the ratio is set to 2:1 and the input is 35dBfs, the output signal will be 40dBfs. Since the input level is 5dB below the threshold, the 2:1 ratio doubles this gap to 10dB.
The RATIO knob controls the amount of expansion that will happen once the input signal crosses the T H R E S H O L D level, described above. Ratio controls how much the input signal will be reduced as a ratio of the input signal level. For example, if the threshold level is set to 30dBfs, the ratio is set to 2:1 and the input is 35dBfs, the output signal will be 40dBfs. Since the input level is 5dB below the threshold, the 2:1 ratio doubles this gap to 10dB. The far right setting of the Ratio control, GATE is used for gating. This means that there will be no output signal when the input is below the threshold.
chapter 4 basics of expansion
The KNEE knob is used to vary between Hard and Soft knee expansion styles. When the CLX-440 is set for Hard knee, the expansion ratio applies only to signals below the threshold level. If the CLX-440 is set for Soft knee, the expansion ratio gradually increases from 1:1 to the currently selected ratio over a range of approximately 5 dB, so that the transition from unexpanded to expanded is more gradual. The difference between Hard Knee and Soft Knee is more obvious at high expansion ratios (gating). Once the input signal crosses the Threshold, the unit will compress the signal at the full ratio level.
In most cases, you will want to use the Hard Knee setting for Gating. This gives you a punchy sound on percussion and other transient sounds. Soft knee expansion can be useful if the gate is too noticeable. Softening the knee lets the gate gradually fade in, instead of cutting in and out.

Electric Guitar

Funky rhythm guitar parts love compression. Not only does it make the part punch out the mix better, it evens out the volume of the muted strums. The following setting, with its low threshold and high ratio, gives you lots of compression for punching up a funky rhythm guitar part: Threshold set for constant compression (around -3dB) Ratio set for 6:1 Knee set for Soft Peak/RMS set for RMS
Experiment with turning the Threshold up or down for a thinner or chunkier tone.
Compressor Applications using the Sidechain

De-essing

Occasionally when recording vocals, the letter "s" seems to jump out louder than the rest of the part. This is because sibilant letters, especially the letter s, have more high frequency energy than other letters. This can cause tape recorders or other components to distort, even though the level may not seem very loud. This "sibilance" can sometimes be eliminated by moving the microphone, but often a de-esser is required.

Input Output To Recorder

Mic Pre

Compressor

Direct Out

Microphone

Sidechai n Input Output
The CLX-440 allows you to perform de-essing on a track by using a sidechain. By placing an equalizer, such as the PEQ-450, in the sidechain, you can set the CLX-440 so that only certain frequency ranges trigger the unit to start compressing. The trick is to set the EQ to cut all frequencies except for the sibilant range, between 3-6kHz. Then set the CLX-440 like this: Threshold set around 0dB Ratio set for 6:1 Attack set at minimum (0.2ms) Release set around 8 oclock Knee set for Hard Detection set for Peak
The Threshold should be set so that an "s" triggers about -3 to -6 dB of compression. If other sounds are triggering the compressor, you might need to adjust the EQ cutoff frequencies.

chapter 5 applications

Ducking
Ducking is often used when doing voiceovers. It allows background music to automatically be turned down whenever a external source, such as an announcers voice, begins to speak. You can also use ducking to have one instrument push the other out of the way, such as the bass guitar ducking every time the kick drum hits.

Music Input Input

Microphone CD Player

Mic Input

Sidechain Mic Direct Out
To make the CLX-440 into a ducker, plug the source into the inputs and plug the trigger into the SIDECHAIN input. The DIRECT OUT isnt used in this example. In the example below, the sound of a radio announcers voice will automatically turn the music down when he speaks and it will slowly fade back in when he stops: Set the CLX-440 controls like this: Threshold set for +3dB (around 3 oclock) Ratio set for 6:1 Knee set for Soft Peak/RMS set for Peak Attack set around 9 oclock Release set around 2 oclock
Plug the announcers mic into the mixer, and feed that mic to the CLX-440s Sidechain in. When the announcer speaks, the music will duck down (turn the ratio up to duck it even lower). When he finishes speaking, the music will fade back up at a rate set by the Release knob.

Expander Applications

Gating a Noisy Guitar Amp
When a rock guitar amp is set loud enough to sound good it usually creates quite a bit of hiss. These settings will mute the guitar when it isnt playing. Ratio set to Gate Attack set to minimum (.02ms) Hold set to minimum (0ms) Release set around 2 oclock (1 second) Knee set to Hard
The Threshold should be set so that the Gate opens when the guitar is playing and closes when the guitar stops. Try turning the threshold all the way down when the guitar is not playing, turn it up until it opens then turn it back down a bit. Experiment with the release time to make a smooth transition from open to closed.
Expanding Live Vocal Tracks
In some cases, it may be better to use expansion than gating. For example, imagine that a band was recorded in concert. The vocal track will probably have "bleed" from the rest of the instruments on stage. If you gate the vocal, you will still hear the other instruments when the vocalist is singing. When the gate closes, the listener will be distracted by the change in tone when those instruments are no longer playing through the vocal channel. So, to expand the vocal, we will use these settings: Ratio set to 2:1 Attack set to minimum (.01ms) Hold set to minimum (0ms) Release set around 2 oclock (1 second) Knee set to Hard
Adjust the Threshold so that the rest of the band is attenuated when the vocalist isnt singing.
Expander Applications using the Key

Gated Reverb

A popular effect for drums is to use distant room mics or a digital reverb set to a long decay, then gate them so that the reverb suddenly cuts off. To do this we will use the snare drum as a key to open the reverb gate. 1. 2. Plug the output of the room mics or reverb into the input of the CLX-440 Plug the snare drum signal into the Key input of the CLX440 You may need to bus the snare drum signal using a direct out or effects send so you can use it in the mix and for the key signal. 3. 4. 5. Set the controls this way: Ratio set to Gate Attack set to minimum (.02ms) Hold set to 12 oclock (100ms) Release set to minimum (1ms) Knee set to Hard Set the Threshold so that the snare drum makes the room sound open up for a moment, then close. Use the Hold setting to control the length of the reverb sound.

Tip: While youre at it, try compressing the room mics a bit. On second thought, compress the living daylights out of the room mics. The more the better.
Key Filtering for a Tom Mic gate
It is often useful to filter the input before it is detected. It keeps other sounds from crossing the threshold and opening the gate. For this example, we will gate a floor tom mic. When the floor tom channel is constantly open, we hear too much of the rest of the kit. This effects the definition and imaging of the drum kit recording. The solution is to gate the floor tom and pan it hard right. However, when we try this, the snare drum is loud enough that it occasionally opens the floor tom gate. This means we need to filter the signal before it reaches the detector. 1. 2. 3. Plug the DIRECT OUT of the CLX-440 into the input of an equalizer, such as the Alesis PEQ-450. Plug the EQ output into a mixer input for now so that you can hear the effects of the EQ. A floor tom has a lower resonant frequency than a snare drum. Use the EQ filters to cut all frequencies except for the resonant frequency of the floor tom. This is probably around 250Hz. Dont worry if this signal sounds ugly. This is not what the finished result will sound like. This filter is simply helping the detector ignore the snare drum. 4. 5. Plug the output of the EQ into the KEY input on the rear panel of the CLX-440. Press the KEY button for the channel you are using on the CLX-440.
The gate should now only open when the floor tom is hit, and should ignore the snare drum hits. Tip: You can compress the signal in addition to gating it. Try adding a bit of punchy compression to the drum tracks.
Staccato Gating a Synth Pad
An interesting effect using the KEY input is to key a sustained sound from another, completely unrelated sound. This works well when the signal being keyed is a legato part that doesnt change much and the key input signal is a percussive sound. This example will combine a simple string pad performance, playing whole notes, with a 16th note drum machine hi-hat to create a staccato synth effect. 1. 2. 3. 4. Plug the synth pad track into the channel INPUT of the CLX440. Plug the hi-hat signal into the KEY input of the same channel. Press the KEY button for the channel you are using on the CLX-440. Adjust the gate controls so that the string part plays at the same staccato rhythm as the hi-hat.

String Pad

Key Input

Gated String Pad

Hi Hat

Chapter 6

Troubleshooting

Troubleshooting Index

If you experience problems while operating your CLX-440, please use the following table to locate possible causes and solutions before contacting Alesis Product Support for assistance.
Symptom No audio from outputs Cause No input audio Bad cables Destination is turned down Solution Test with a known good input. Replace the cables. Check the connections and the level of the mixer or amp that the CLX-440 is connected to. Turn them up Decrease the Expander Threshold and Ratio until Gain Reduction lights go away Press the Sidechain button so that it is off (not lit). Go take a walk

Input or output control is turned down Gate is on
Sidechain is on Power is not connected Cables are crossing a power cable Make sure that the CLX-440 and its audio cables are kept away from power cables, and wall warts.

Buzz from outputs

troubleshooting chapter 6
Bad cables Problem with the source

AC hum

Ground loop
Replace the cable with a new, highquality cable. Try bypassing the CLX-440 by connecting the input cables to the output cables and see if the problem remains. Use only balanced connections in the studio Place all equipment in the studio on a common ground (see next page)
Avoiding ground loop noise
In todays studio, where it seems every piece of equipment has its own computer chip inside, there are many opportunities for ground loop problems to occur. These show up as hums, buzzes or sometimes radio reception and can occur if a piece of equipment "sees" two or more different paths to ground. While there are methods to virtually eliminate ground loops and stray radio frequency interference, most of the professional methods are expensive and involve installing a separate power source just for the sound system. Alternatively, here are some helpful hints that professional studio installers use to keep those stray hums and buzzes to a minimum. KEEP ALL ELECTRONICS OF THE SOUND SYSTEM ON THE SAME AC ELECTRICAL CIRCUIT. Most stray hums and buzzes happen as a result of different parts of the sound system being plugged into outlets of different AC circuits. If any noise generating devices such as air conditioners, refrigerators, neon lights, etc., are already plugged into one of these circuits, you then have a perfect condition for stray buzzes. Since most electronic devices of a sound system dont require a lot of current (except for power amplifiers), its usually safe to run a multi-outlet box or two from a SINGLE wall outlet and plug in all of the components of your system there.
chapter 6 troubleshooting KEEP AUDIO WIRING AS FAR AWAY FROM AC WIRING AS POSSIBLE. Many hums come from audio cabling being too near AC wiring. If a hum occurs, try moving the audio wiring around to see if the hum ceases or diminishes. If its not possible to separate the audio and AC wiring in some instances, make sure that the audio wires dont run parallel to any AC wire (they should only cross at right angles, if possible). TO ELIMINATE HUM IF THE ABOVE HAS FAILED: A) Disconnect the power from all outboard devices and tape machines except for the CLX-440, the mixer and control room monitor power amp. B) Plug in each tape machine and outboard effects device one at a time. If possible, flip the polarity of the plug of each device (turn it around in the socket) until the quietest position is found. C) Make sure that all of the audio cables are in good working order. Cables with a detached ground wire will cause a very loud hum!! D) Keep all cables as short as possible, especially in unbalanced circuits. If the basic experiments dont uncover the source of the problem, consult your dealer or technician trained in proper studio grounding techniques. In some cases, a "star grounding" scheme must be used, with the mixer at the center of the star providing the shield ground on telescoping shields, which do NOT connect to the chassis ground of other equipment in the system.

troubleshooting chapter 6 Customers outside the USA and Canada: Contact your local Alesis distributor for any warranty assistance. The Alesis Limited Warranty applies only to products sold to users in the USA and Canada. Customers outside of the USA and Canada are not covered by this Limited Warranty and may or may not be covered by an independent distributor warranty in the country of sale. Do not return products to the factory unless you have been given specific instructions to do so. Internet Address: Important information and advice is available on our web site: http://www.alesis.com Email may be addressed to: Support@alesis.com

Specifications

Subject to change without notice Audio Input Input Connectors: Nominal Input Level: Maximum Input Level: Input impedance: Sidechain/ Key Inputs Input Connectors: Nominal Input Level: Maximum Input Level: Input impedance: Direct Output Output Connectors: Output Level-Stereo Input : Output Level-Mono Input : Output impedance: Audio Output +4dBu/-10dBV Switchable Output Connectors: Nominal Output Level (+4dBu): Maximum Output Level (+4dBu): Output impedance: Audio Performance Signal to Noise Ratio:
4 Balanced 1/4" TRS jacks Adjustable from -10dBV to +4dBu = -15dBFS +20dBu (7.78 Vrms) 10 kOhm
4 Balanced 1/4" TRS jacks (2 Sidechain, 2 Key) +4 dBu (1.23 Vrms) = -15 dBFS +19 dBu (6.9 Vrms) = -0 dBFS 10 kOhm
2 Impedance-balanced 1/4" TRS jacks (Left In - 6.02dB) + (Right In - 6.02dB) Left/Mono In 220 Ohm
4 Impedance-balanced 1/4" TRS jacks +4 dBu (1.23 VRMS) = -15 dBFS +19 dBu (6.9 VRMS) = -0 dBFS 220 Ohm
>103 dB A-Weighted, Analog In to Analog Out
troubleshooting chapter 6 THD+N: Frequency Response: Power consumption: <0.003%, Analog In to Analog Out 22-22 kHz 0.50 dB, Analog In to Analog Out 7 Watts Max (90-230 VAC / 50-60 Hz)
Mechanical Size: Rack spaces: Weight:
3.5" H x 19.0" W x 6" D (89mm H x 483mm W x 152mm D) 2 Spaces 5 lbs (2.27 kg)
All measurements done over a 22 Hz - 22 kHz range with 1 kHz sine wave at -1dBFS input. Impedances are measured at 1 kHz.

Alesis Limited Warranty

ALESIS STUDIO ELECTRONICS ("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. During the warranty period ALESIS shall, at its sole and absolute option, either repair or replace free of charge any product that proves to be defective on inspection by ALESIS or its authorized service representative. In all cases disputes concerning this warranty shall be resolved as prescribed by law. To obtain warranty service, the purchaser must first call or write ALESIS at the address and telephone number printed below to obtain a Return Authorization Number and instructions concerning where to return the unit for service. All inquiries must be accompanied by a description of the problem. All authorized returns must be sent to ALESIS or an authorized ALESIS repair facility postage prepaid, insured and properly packaged. Proof of purchase must be presented in the form of a bill of sale, canceled check or some other positive proof that the product is within the warranty period. ALESIS reserves the right to update any unit returned for repair. ALESIS reserves the right to change or improve design of the product at any time without prior notice. This warranty does not cover claims for damage due to abuse, neglect, alteration or attempted repair by unauthorized personnel, and is limited to failures arising during normal use that are due to defects in material or workmanship in the product. THE ABOVE WARRANTIES ARE IN LIEU OF ANY OTHER WARRANTIES OR REPRESENTATIONS WHETHER EXPRESS OR IMPLIED OR OTHERWISE, WITH RESPECT TO THE PRODUCT, AND SPECIFICALLY EXCLUDE ANY IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MERCHANTABILITY OR OTHER IMPLIED WARRANTIES. Some states do not allow limitations on how long an implied warranty lasts, so the above limitation may not apply to you.

troubleshooting chapter 6 IN NO EVENT WILL ALESIS BE LIABLE FOR INCIDENTAL, CONSEQUENTIAL, INDIRECT OR OTHER DAMAGES RESULTING FROM THE BREACH OF ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING, AMONG OTHER THINGS, DAMAGE TO PROPERTY, DAMAGE BASED ON INCONVENIENCE OR ON LOSS OF USE OF THE PRODUCT, AND, TO THE EXTENT PERMITTED BY LAW, DAMAGES FOR PERSONAL INJURY. Some states do not allow the exclusion or limitation of incidental or consequential damages, so the above limitation or exclusion may not apply to you. THIS CONTRACT SHALL BE GOVERNED BY THE INTERNAL LAWS OF THE STATE OF CALIFORNIA WITHOUT REFERENCE TO CONFLICTS OF LAWS. This warranty gives you specific legal rights, and you may also have other rights required by law which vary from state to state. This warranty only applies to products sold to purchasers in the United States of America or Canada. The terms of this warranty and any obligations of Alesis under this warranty shall apply only within the country of sale. Without limiting the foregoing, repairs under this warranty shall be made only by a duly authorized Alesis service representative in the country of sale. For warranty information in all other countries please refer to your local distributor.
ALESIS Los Angeles, CA www.alesis.com
Alesis Studio Electronics, Los Angeles, CA 2001 Alesis Studio Electronics Specifications Subject To Change Without Notice

Freddie Katz Equipment List
Pro Tools 8 Mac G5 Soundtracs Topaz Mics: Shure AKG CAD Audio Technica Rode EV Mic Preamps: Focusrite Voicemaster Focusrite Trakmaster Focusrite Octopre Joemeek VC6Q Presonus Dynamics: DBX 166 (3) DBX 118 Symetrix CL 150 (3), CL 100 (3), 525 Ashly CL50E (2) FMR RNC (2) Orban 412A Alesis CLX440 Valley People Gatex Processing: Lexicon MPX 500 TC Electronic M1 TC Electronic D2 Yamaha Rev 500 Yamaha SPX 90 Roland SRV 3030 Deltalabs Effectron ADM 1024 Korg SDD 2000 Korg SDD 1200 Orban 622B Parametric EQ Alesis PEQ-450 Parametric EQ
Monitors: Mackie MR8 Tannoy PBM 6.5 Tannoy SBM Instruments: Fender Stratocaster (2) Gibson Les Paul Studio Gibson Les Paul Jr. Kramer Bass Takamine Acoustic Guitar Dan Electro Guitar M-Audio 61 key Midi Controller Keyboard Assorted Percussion (tamborines, shakers, clave, etc.) Various guitar effects pedals Amplifiers: Marshall JCM Fender "The Twin" (red knob "evil" twin) Carvin Bass Amp