ALESIS NanoCompressor

Reference Manual

Introduction

INTRODUCTION
Thank you for purchasing the Alesis NanoCompressor Dynamics Processor. To take full advantage of the NanoCompressors functions, and to enjoy long and troublefree use, please read this users manual carefully.

How To Use This Manual

This manual is divided into the following sections describing the various functions of the NanoCompressor. Though we recommend you take time to read through the entire manual once carefully, those having general knowledge about compressor/limiters should use the table of contents to look up specific functions. Chapter 1: Your First Session with the NanoCompressor. This chapter is a basic introduction for connecting and operating the NanoCompressor. Chapter 2: Connections. This chapter explains how to connect the NanoCompressor to an instrument, mixing console or amplifier. Chapter 3: Description of Controls. An explanation of all connectors and knobs on the NanoCompressor. Use this chapter as a quick reference guide when searching for specific information. Chapter 4: Applications. This chapter lists several applications for the NanoCompressor, and suggests ways of connecting and operating the unit in these situations. Chapter 5: Troubleshooting. This chapter contains troubleshooting tips and service information should problems occur.

Conventions

The knobs and rear panel connectors are referred to in this manual just as their names appear on the NanoCompressor, using all capital letters and in brackets (Example: [RATIO] Knob, [SIDECHAIN] jack, etc.).
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 NanoCompressor.

NanoCompressor Manual

Your First Session with the NanoCompressor

CONTENTS

Your First Session with the NanoCompressor..7
Unpacking and Inspection... 7 Basic Connections..... 7 Setting Levels..... 8 Whats on the Front Panel?.... 8 Auditioning The Compressor... 10 Bypassing Compression.... 10 Placement and Installation... 10 Rack Mounting.... 10

Connections...11

AC Power Hookup.... 11 Line Conditioners and Protectors.... 11 Audio Connections.... 11 Typical Applications.... 12 Connecting Directly to an Instrument... 12 Mixer Inserts.... 13 Using the NanoCompressor with a Powered Mixer. 14 Mixer Main Outputs.... 14 Avoiding Ground Loops.... 14
Description of Controls...17
Front Panel..... 17 Threshold..... 17 Ratio.... 17 Attack.... 18 Release.... 18 Pumping and Breathing... 18 Output..... 18 Hard/Soft.... 19 Peak/RMS.... 19 Input/Output.... 19 Bypass/Comp.... 19 Rear Panel..... 20 Power.... 20 Sidechain.... 20 Input (Left/Mono & Right)... 20 Output (Left & Right).... 20

Applications...21

Instrument Settings.... 21 Vocal Limiting.... 21 Vocal Compression and Spoken Word... 21 Drums..... 21 Bass..... 22 Electric Guitar.... 22 Sidechain Applications.... 22 De-Essing..... 22 Ducking.... 23

Troubleshooting..27

Trouble-Shooting Index... 27 Maintenance/Service.... 28 Cleaning.... 28
Contents Refer All Servicing To Alesis... 28 Obtaining Repair Service... 28 Customers in the USA and Canada... 28 Customers outside the USA and Canada.. 28

Specifications...29

CHAPTER 1

YOUR FIRST SESSION

WITH THE NANOCOMPRESSOR

Unpacking and Inspection

Your NanoCompressor was packed carefully at the factory, and the shipping carton was designed to protect the unit during shipping. Please retain this container in the highly unlikely event that you need to return the NanoCompressor for servicing. The shipping carton should contain the following items: This instruction manual Alesis NanoCompressor with the same serial number as shown on shipping carton AC Power Supply Adapter (Alesis P3) Mounting Screw and Rubber Feet Alesis warranty card
It is important to register your purchase; if you have not already filled out your warranty card and mailed it back to Alesis, please take the time to do so now.

Basic Connections

The NanoCompressor will work in many different applications, whether you are connecting an instrument directly into it, or connecting it with a mixing console. Briefly described here are the basic connections to get you up and running quickly. For more information on connections, please refer to Chapter 2. Mono. Connect a 1/4" phone cord to the [LEFT] INPUT of the NanoCompressor from a mono source. Connect another 1/4" phone cord from the [LEFT] OUTPUT of the NanoCompressor to an amplification system or mixer input.
Stereo. Connect two 1/4" phone cords to the [LEFT] & [RIGHT] INPUTS of the NanoCompressor from a stereo source, and two 1/4" phone cords from the [LEFT] & [RIGHT] OUTPUTS of the NanoCompressor to a stereo amplification system or two mixer inputs. Insert. This is the most common application for a compressor. Acquire an Insert cable, which has a balanced 1/4 plug on one end of the cable and two mono 1/4 plugs on the other. First, connect the send from the mixer (typically connected to the tip of the insert, but check your mixers reference manual) to the [LEFT] INPUT of the NanoCompressor. Connect the other mono connector to the [LEFT] OUTPUT of the NanoCompressor to return the signal to the mixer. Finally, plug the stereo insert jack into the mixer insert.
Compression is a dynamic effect that is applied to an entire signal. Unlike reverb or delay, where a new sound is created and added to the original sound, the compressor should have the complete signal going through it. This is why compressors are patched into mixer inserts, instead of being patched into effects sends and returns like digital effects processors.

Bypassing Compression

At any time you can bypass the compressor, thereby allowing the direct signal to pass through the NanoCompressor unchanged. This is done by pressing the [BYPASS/COMP] switch so that it is set for COMP (pushed out). Note that the [OUTPUT] knob does not function when the NanoCompressor is bypassed.
Placement and Installation
The NanoCompressor may be mounted almost anywhere it's needed: on a table, on top of an amp, or next to a mixing console. In any case, make sure to place it safely where it will not fall or be damaged. If it will be on furniture, make sure to attach the provided rubber feet to the bottom of the unit. While the NanoCompressor itself doesn't generate any magnetic or hum fields, its power supply may do so. Make sure to place the power supply away from other audio equipment that is sensitive to induced fields, and away from the signal wiring. In rare instances, the NanoCompressor itself may pick up noise fields generated by other equipment such as large power amplifiers; in this case, move the NanoCompressor until the noise goes away.

Rack Mounting

The most secure mounting is on a "universal" rack shelf, available from various rack manufacturers or your music dealer. The NanoCompressor's height conforms to single-space mounting, and up to three NanoCompressors may be mounted side-byside in a standard universal EIA 19" equipment rack.

Connections

CHAPTER 2

CONNECTIONS

AC Power Hookup
The NanoCompressor comes with a power adapter suitable for the voltage of the country it is shipped to (either 110 or 220V, 50 or 60 Hz). To turn on the NanoCompressor, plug the small end of the power adapter cord into the NanoCompressors [POWER] socket and the male (plug) end into a source of AC power. Its good practice to not plug in the NanoCompressor until all other cables are hooked up.
Alesis cannot be responsible for problems caused by using the NanoCompressor or any associated equipment with improper AC wiring.
Line Conditioners and Protectors
Although the NanoCompressor is designed to tolerate typical voltage variations, in todays world the voltage coming from the AC line may contain spikes or transients that can possibly stress your gear and, over time, cause a failure. There are three main ways to protect against this, listed in ascending order of cost and complexity: Line spike/surge protectors. Relatively inexpensive, these are designed to protect against strong surges and spikes, acting somewhat like fuses in that they need to be replaced if theyve been hit by an extremely strong spike. Line filters. These generally combine spike/surge protection with filters that remove some line noise (dimmer hash, transients from other appliances, etc.). Uninterruptible power supply (UPS). This is the most sophisticated option. A UPS provides power even if the AC power line fails completely. Intended for computer applications, a UPS allows you to complete an orderly shutdown of a computer system in the event of a power outage, and the isolation it provides from the power line minimizes all forms of interferencespikes, noise, etc.

Audio Connections

The connections between the NanoCompressor and your studio are your musics lifeline, so use only high quality cables. These should be low-capacitance shielded cables with a stranded (not solid) internal conductor and a low-resistance shield. Although quality cables cost more, they do make a difference. Route cables to the NanoCompressor correctly by observing the following precautions: Do not bundle audio cables with AC power cords. Avoid running audio cables, or placing the NanoCompressor itself, near sources of electromagnetic interference such as transformers, monitors, computers, etc. Never unplug a cable by pulling on the wire itself. Always unplug by firmly grasping the body of the plug and pulling directly outward.
Connections Do not place cables where they can be stepped on. Stepping on a cable may not cause immediate damage, but it can compress the insulation between the center conductor and shield (degrading performance), or reduce the cables reliability. Avoid twisting the cable or having it make sharp, right angle turns.

Typical Applications

The audio inputs and outputs are typically used in one of three ways: from the output of a line-level instrument (like a guitar or keyboard with either a mono or stereo output), and out to an amplifier or mixer input; or, from the insert of a mixer channel or master out from the stereo buss outputs of a mixer to a mix-down tape machine or amplifier.
These applications are outlined and illustrated in detail on the following pages.
Connecting Directly to an Instrument
When connecting audio cables and/or turning power on and off, make sure that all devices in your system have their volume controls turned down. The NanoCompressor has two 1/4 unbalanced inputs and two 1/4 unbalanced outputs. These provide two different audio hookup options: Mono. Connect a 1/4" phone cord to the [LEFT] INPUT of the NanoCompressor from a mono source, and another 1/4" phone cord from the [LEFT] output of the NanoCompressor to an amplification system or mixer input.
If your amplifier has an effects loop, plug the effects out of the amp into the NanoCompressor and the Output of the NanoCompressor back into the amplifiers effects in.
Stereo. Connect two 1/4" phone cords to the [LEFT] and [RIGHT] INPUTS of the NanoCompressor from a stereo source , and two other 1/4" phone cords from the [LEFT] and [RIGHT] OUTPUTS of the NanoCompressor to a stereo amplification system or two mixer inputs.
Note: This hookup will work only for a stereo source, and should not be used on two independent mono sources. This is because the NanoCompressor is designed for stereo linked operation between the two channels, so the left input will reduce the level of the right input and vice versa.

Mixer Inserts

If your mixer features individual channel or buss inserts, you can dedicate the NanoCompressor to a specific channel or buss on the mixer. Insert jacks on the back of a mixer provide a way of inserting external processing equipment into the signal path. The insert occurs after the input amplifier, and before the channel fader; essentially it is the same as connecting the source (instrument or microphone) into the NanoCompressor before the mixers channel input. If nothing is connected to the channels Insert jack, the signal passes through with no effect. Usually, insert connections require a special, stereo-splitting Y-cord to be connected (one stereo plug provides both send and return while two mono plugs connect separately to the effects units input and output). These are known as TRS connectors (tip-ring-sleeve). The tip of the stereo plug typically carries the send or output of the insert jack, while the ring carries back the return. (You should check your mixers referance manual to see if it follows this polarity.) The sleeve represents a common ground for both signals. This involves connecting a 1/4" TRS (tip-ring-sleeve) Y-cable to the Insert jack of a single channel on a mixing console. The other end of the cable (which splits into two, 1/4" mono connectors) are connected to the [LEFT] input and [LEFT] output, respectively. If you do not hear any audio after making these connections, swap the input and output cables at the NanoCompressor, as these may be wired backwards. Once the proper connection has been made, you must set the output level so that you arent clipping the mixer input. As a general rule, if the [REDUCTION] meter is showing an average -6 dB of gain reduction, the [OUTPUT] knob should be set for +6dB (one tick above the 0 marker).
Using the NanoCompressor with a Powered Mixer
You can dramatically improve the sound quality of a powered mixer by connecting the NanoCompressor to it in the same way you would connect it to a regular mixer, with one important note:
Never connect an output intended for a loudspeaker (the power amplifier output) to the input of the NanoCompressor. This will cause damage that will not be covered by the warranty. Consult the manual of your mixer for more information. Generally, the best way is to connect the "Master Insert" jack of the mixer to the NanoCompressor following the procedure on page 13. If the system is not stereo, you may connect only the [LEFT] side of the NanoCompressor to the mixers Master Insert. You can also connect the NanoCompressor (or multiple NanoCompressors) to the individual channel insert(s). Note: Be careful not to use too much compression when mixing live sound, the speakers may feed back with too much gain reduction on the PA.

Mixer Main Outputs

Some mixers, such as live PA boards and small home studio mixers, may not have inserts on the channels or even the main out. In this case, you can still use the NanoCompressor to control peaks by putting the NanoCompressor between the Main Output of your mixer and the Input of your power amp or tape recorder. Note: During studio mixdown, if the output of the mixer is feeding a compressor before the mixdown tape deck and the song fades out, the sound of the mix will probably change as it fades. This is why its better to use the Main Inserts if they are supplied on your mixer, since these are typically pre-fader. See your mixers reference manual for more information.

Avoiding Ground Loops

In todays studio, where it seems every piece of equipment has complex routing and computer logic, 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. Here are some easy helpful hints that a professional studio installer might 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.

KEEP AUDIO WIRING AS FAR AWAY FROM AC WIRING AS POSSIBLE.
Many hums come from audio cabling being too near AC wiring or the power transformers used by equipment requiring an external supply. 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 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.
Note that the NanoCompressor, with its external low-voltage power supply, has no power supply ground. Its power is transformer isolated for safety, so it has no need for a "safety ground". Signal ground is connected to chassis ground at the input and output jacks (as it is in most unbalanced equipment). If the NanoCompressor is attached to a metal rack mounting shelf, the assembly shares a common ground with the other equipment in the same rack. In some cases (such as a star ground scheme), you may wish to use nonconductive rack rails or rack isolators to avoid ground loops.
To avoid the possibility of electric shock, never defeat the safety ground found on other equipment in the system. When in doubt about proper electrical grounding schemes or the power to your system, consult a qualified, licensed electrician.

Description of Controls

CHAPTER 3

DESCRIPTION OF CONTROLS

Front Panel

Threshold

The [THRESHOLD] knob sets the level where compression will begin. As long as the input signal level is below the Threshold level, the NanoCompressor will do nothing to the signal. Once the input signal crosses the Threshold, the NanoCompressor will begin compressing at a ratio set by the [RATIO] control.
In the diagram above, Figure (a.) shows the input signal to the NanoCompressor. In this example the compressor Threshold is set for -10dB and the Ratio is set for 4:1. When the third peak of the input signal crosses the Threshold, the NanoCompressor starts to reduce the signal level, as shown in Figure (b.). Figure (c.) shows the output signal level, with the original signal shown with a dotted line.

The [RATIO] knob controls the amount of compression which will happen once the input signal crosses the [THRESHOLD] 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 compression ratio is set for 6:1, the input signal will have to cross the threshold by 6 dB for the output level to increase by 1dB. The tick marks around the Ratio control show several ratio settings for reference. These are, in clockwise order: 1:1, 2:1, 4:1, 8:1, 10:1, and :1. The far right setting, :1 (Infinity to 1), is used for Limiting. This means that the input signal wont go above the threshold at all.

Attack

The [ATTACK] knob controls the amount of time before compression starts. The range of this control is 0.1 to 200 milliseconds. The Attack and Release controls only function when the NanoCompressor is in Peak mode. Long attacks are useful for percussive sounds, where shorter attacks are good for melodic parts like vocals and strings. The Attack control is also useful for keeping the transients on percussive drum or bass sounds. Experiment with different short attack times on snare drums to get more or less of the stick attack.

Release

The [RELEASE] knob controls the amount of time the compressor takes to stop compressing after the signal crosses under the threshold. The range of this control is 50ms to 3 seconds. The Attack and Release controls only function when the NanoCompressor is in Peak mode. Short release times are good for percussive, punchy sounds, where longer release times can make compression less obvious on vocals. Adjusting the release time may be necessary when using extreme compression and pumping or breathing is audible, or if lower level signals after peaks are getting lost.

Pumping and Breathing

When a compressor is making large changes to the input signal (10 to 12 dB or more), the noise floor will also rise and fall with the signal level. When this noise signal rises and falls drastically between signals, such as a heavily compressed, noisy drum track, you might hear the noise level breathing between drum hits. One solution to this breathing problem is to turn up the release time. This way, the noise floor wont have time to rise between drum hits. However, if the Release time is too long, lower level signals after the peak will be lost as the compressor slowly stops reducing gain. This is called pumping as the lower level signals (noise included) slowly fade back up to their normal signal level. The secret to avoiding these problems is to achieve a balanced release time on the input signal.

Output

The [OUTPUT] knob controls the level of the NanoCompressors output. The Output control is useful for making up gain which was reduced by the compression circuit or matching the input level of a mixer or recorder. If the REDUCTION meter shows that the input signal is being attenuated by -6dB, then the Output control generally should be set around +6dB. The [OUTPUT] knob is labeled with tick marks every 6 dB (6, 12, 18, 24dB). This control is disabled if the [BYPASS] button is pressed.

Vocal Limiting

Vocalists tend to be one of the most dynamic recording challenges in any studio or stage. Even though a singer may go from a whisper to a scream during the course of a song, its the engineers job to keep the vocals level in line with the rest of the ensemble. You can do this by setting the compressor with a high ratio and a high threshold. This way, softer sections will go by uncompressed, and louder peaks will be kept under control. Threshold set so that the loudest sections get around -6 of reduction(usually around 3 oclock) Ratio set for 6:1 Knee set for Soft Peak/RMS set for RMS The Threshold should be set so that loud sections get compressed around 6dB and quiet passages get no compression at all.
Vocal Compression and Spoken Word
In other cases, you may want to compress the entire dynamic range of a vocal. This is typical of pop vocals and voiceovers for radio commercials. Whenever there is signal, there is some compression taking place; just barely on the soft passages, and up to 12 dB of reduction during loud passages. Threshold set so that one REDUCTION LED (-1 dB) lights during the softest passages with signal (usually around 11 o'clock) Ratio set for 2:1 Peak/RMS set to Peak Attack set to 0.1 ms (7 o'clock) Release set between 10 and 12 o'clock (100 ms.) Raise output to compensate for gain reduction
Engineers often compress drum tracks just to get a nice punchy sound in the mix. The settings below sound good on a rock snare drum: Threshold set so that all drum hits are compressed (around -3dB) Ratio set for 4:1 Knee set for Soft Peak/RMS set for Peak Attack set around 8 oclock Release set around 9 oclock By turning the Threshold down even more, you can squash the snare drum as much as you want. Turn the attack up (longer) to get more stick out of the snare drum, and turn it down for a synth pop slap.
Since bass guitar forms the foundation of most Rock and Jazz music, its important that the level of the Bass doesnt jump around in the mix. Also, adding compression to bass tracks (or almost anything else) can make it punchier, generally a good thing in rock tunes. Try the settings below on a rock bass track: Threshold set so only the peaks are compressed (around 0dB) Ratio set for 4:1 Knee set for Hard Peak/RMS set for Peak Attack set around 9 oclock Release set around 10 oclock

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.

Troubleshooting

Chapter 5

TROUBLESHOOTING

Troubleshooting Index
If you experience problems while operating the NanoCompressor, please use the following table to locate possible causes and solutions before contacting Alesis Product Support for assistance.

Symptom

The Power LED does not light when the unit is powered on Sound is distorted, Red Input LED is lit Sound is distorted, Red Output LED is lit Sound is distorted, neither the Red Input nor the Red Output LEDs are lit Sound is excessively noisy, Green Input LED barely lit No audio is heard
No power Input level is too high Output level is too high Too much compression Input level is too low Output level is too low

Solution

Check that the power cable is plugged in properly Turn down the level going to the input Turn down the Output level control Turn the Ratio down or the Threshold up Turn up the level going to the input Turn the Output control to the right Unplug the Sidechain cable

Hum or noise from output

Feedback in PA system when compression stops Unit does not respond to front panel controls
Sidechain jack is connected with nothing on the other side Ground loop, unshielded Try plugging the unit into cables another power jack or using different audio cables Excessive compression at Raise threshold and lower low thresholds output level System level is too close Lower input level or to threshold point output, adjust threshold to compensate Unit is Bypassed Make sure the Bypass/Comp switch is out Unknown electrical Power down and power up conflict, vampires, or again static electricity

Maintenance/Service

Cleaning
Disconnect the AC cord, then use a damp cloth to clean the NanoCompressors 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.
Refer All Servicing to Alesis
We believe that the NanoCompressor is one of the best compressors that can be made using current technology, and should provide years of trouble-free use. However, should problems occur, DO NOT attempt to service the unit yourself. Service on this product should be performed only by qualified technicians. NO USERSERVICEABLE PARTS INSIDE.

Obtaining Repair Service

Before contacting Alesis, check over all your connections, and make sure youve read the manual. Customers in the USA and Canada: If the problem persists, call Alesis USA at 1-8005-ALESIS and request the Product Support department. Make sure you have the units serial number with you. Talk the problem over with one of our technicians; if necessary, you will be given a return order (RO) number and instructions on how to return the unit. All units must be shipped prepaid and COD shipments will not be accepted. For prompt service, indicate the RO number on the shipping label. Units without an RO will not be accepted. If you do not have the original packing, ship the NanoCompressor in a sturdy carton, with shock-absorbing materials such as Styrofoam pellets (the kind without CFCs, please) or bubble-pack surrounding the unit. Shipping damage caused by inadequate packing is not covered by the Alesis warranty. Tape a note to the top of the unit describing the problem, include your name and a phone number where Alesis can contact you if necessary, as well as instructions on where you want the product returned. Alesis will pay for standard one-way shipping back to you on any repair covered under the terms of this warranty. Next day service is available for a surcharge. Field repairs are not authorized during the warranty period, and repair attempts by unqualified personnel may invalidate the warranty. Service address for customers in the USA: Alesis Product Support 3630 Holdrege Avenue Los Angeles, CA 90016 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.

Specifications

SPECIFICATIONS

Electrical

Frequency Response: Dynamic Range: Distortion: Crosstalk: 1dB from 20Hz to 20 kHz >109dB, "A" weighting. <0.08% @ 1kHz better than 70dB below full scale
Number of Channels: Format: Nominal Level: Maximum Level: Impedance: 2 1/4" unbalanced -10 dBV (.316 volts) +6 dBV 1M, unbalanced
Number of Channels: Format: Nominal Level Maximum Level: Impedance: Output Level Control Range: 2 1/4" unbalanced -10 dBV, front- panel adjustable +16 dBV 470 ohms 48dB

Compression Specs

Threshold of Limiting: Peak Mode Attack Time: Peak Mode Release Time: RMS Attack/Release Times: Compression Ratio: -40dBv to +8dBV 0.1ms to 200ms 50ms to 3 sec. Program Dependent 1:1 to :1, selectable Hard or Soft compression knee. Front panel ticks indicate 1:1, 2:1, 4:1, 8:1, 10:1 and :1.

Controls: Switches: Meters: THRESHOLD RATIO ATTACK RELEASE OUTPUT Hard/Soft knee, Peak/RMS, Input/Output Meter, Bypass/Comp Reduction (6 LEDs at -30, -20, -12, -6, -3, -1) Signal (6 LEDs at -30, -20, -10, -4, 0, +6)
Input (LEFT, RIGHT) Output (LEFT, RIGHT) Sidechain: Power Dimensions (WxHxD): Weight: 1/4" 2-conductor 1/4" 2-conductor 1/4" Stereo 3-conductor (TRS) 9 Volt Power Transformer (Alesis P3) 5.5 x 1.75 x 4.5 (1/3 rackspace) 1.25 lbs.