Citation

This guide is based off of the Comp16 Users Manual Version 1.0 and is used with permission from PreSonus.

A WORD ABOUT COMPRESSION

Punch, apparent loudness, presence just three of many terms used to describe the effects of compression/ limiting.

Compression and limiting are forms of dynamic range (volume) control. Audio signals have very wide peak to average signal level ratios (sometimes referred to as dynamic range which is the difference between the loudest level and the softest level). The peak signal can cause overload in the audio recording or reproduction chain resulting in signal distortion. A compressor/limiter is a type of amplifier in which gain is dependent on the signal level passing through it. You can set the maximum level a compressor/limiter allows to pass through, thereby causing automatic gain reduction above some predetermined signal level or threshold.

Compression refers basically to the ability to reduce the output level of an audio signal by a fixed ratio relative to the input. It is useful for lowering the dynamic range of an instrument or vocal, making it easier to record without distorting the recorder. It also assists in the mixing process by reducing the amount of level changes needed for a particular instrument. Take, for example, a vocalist who moves around in front of the microphone while performing, thus making the output level vary up and down unnaturally. A compressor can be applied to the signal to help correct this recording problem by reducing the louder passages enough to be compatible with the overall performance.

How severely the compressor reduces the signal is determined by the compression ratio and compression threshold. A ratio of 2:1 or less is considered mild compression, reducing the output by two for signals greater than the compression threshold. Ratios above 10:1 are considered hard limiting. Limiting refers to the point at which the signal is restrained from going any louder at the output. The level of input signal at which the output is reduced is determined by the compression threshold. As the compression threshold is lowered, more and more of the input signal is compressed (assuming a nominal input signal level). Care must be taken not to over compress a signal. Too much compression destroys the acoustical dynamic response of a performance. (Over compression, however, is used by some engineers as an effect, and with killer results!)

Compressor/limiters are commonly used for many audio applications. A kick drum can get lost in a wall of electric guitars. No matter how much level is increased, the kick drum stays lost in the mud. Add a touch of compression and tighten up that kick drum sound allowing it to punch through without having to crank the level way up.

A vocal performance usually has a wide dynamic range. Transients (the very loudest portion of the signal) can be far outside the average level of the vocal signal. It is extremely difficult to ride the level with a console fader. A compressor/limiter automatically controls gain without altering the subtleties of the performance.

A solo guitar can seem to be masked by the rhythm guitars. Compression can make your lead soar above the track without shoving the fader through the roof .

Bass guitar can be difficult to record . A consistent level with good attack can be achieved with proper compression . Your bass doesnt have to be washed out in the low end of the mix . Let the compressor/limiter give your bass the punch it needs to drive the bottom of the track .

COMP16 FRONT PANEL BASIC LAYOUT

The front panel on the COMP16 is divided into three sections. These are:

Presets

Sixteen selectable preset positions

The Presets for the COMP16 are controlled by this sixteen position rotary encoder. As the encoder is rotated, parameters are digitally switched, simultaneously controlling attack, release, ratio and threshold.

Controls

The Input control adjusts the gain on the input amplifier.

Note: The input control is always active.

Output & Pushbuttons

The Output control is used to set the desired output of the COMP16. It is sometimes referred to as gain makeup control. This term is derived from the fact that as the compressor lowers the output level during gain reduction, the overall signal level is lowered, requiring the user to makeup the gain thereby restoring the original signal level.

Output to Meter

This button selects the function of the Output/Gain Reduction meter. Pushed out, the meter gives you the level of the gain reduction. Pushed in, the meter gives you the level of the signal after compression; the output level.

Bypass

If the BYPASS button is not pushed in, the COMP16 is processing the signal (compressing). When pushed in, the COMP16 is no longer compressing the signal, however the input gain setting remains active.

COMP16 BACK PANEL LAYOUT

Input

The input jack accepts balanced/unbalanced tip-sleeve or tip-ring-sleeve connectors or XLR connectors. The input can handle up to +22dBu unbalanced levels.

Output

The output jack accepts (balanced/unbalanced) tip-sleeve, tip-ring-sleeve or XLR connectors. The output will deliver up to +22dBu in signal level unbalanced.

PRESETS

Vocal

SOFT

Easy compression. A low ratio setting for ballads allowing a wider dynamic range. Good for live use. This setting lets the vocal sit in the track.

MEDIUM

More limiting than preset 1 for a narrower dynamic range. It moves the vocal more up front in the mix.

SCREAMER

For loud vocals. Fairly hard compression for a vocalist who is on and off the microphone a lot. It puts the voice in your face.

Perc

SNARE/KICK

Allows the first transient through and compresses the rest of the signal giving a hard snap up front with a longer release.

L/R (Mono) OVERHEAD

A low ratio and threshold gives a fat contour to even out the sound from overhead drum mics. Low end is increased and the overall sound is more present and less ambient. More boom less room.

Fretted

ELECTRIC BASS

A fast attack and slow release to tighten up the electric bass and give you control for more consistent level.

ACOUSTIC GUITAR

This setting accentuates the attack of the acoustic guitar and helps maintain an even signal level keeping the acoustic guitar from disappearing in the track.

ELECTRIC GUITAR

A setting for crunch electric rhythm guitar. A slow attack helps get the electric rhythm guitar up close and personal and gives punch to your crunch.

Keyboards

PIANO

A special setting for an even level. Designed to help even up the top and bottom of an acoustic piano. Helps the left hand be heard with the right hand.

SYNTH

Fast attack and release for synthesizer horn stabs and for bass lines played on a synthesizer.

ORCHESTRAL

Use this setting for string pads and other types of synthesized orchestra parts. It will decrease the overall dynamic range for easier placement in the mix.

Limit

MONO LIMITER

Just as the name implies. A hard limiter setting (brick wall) ideal for controlling level to the 2 track mixdown deck or Mono output.

CONTOUR

A contoured setting for use on the Mono output to fatten up the mix.

Effects

SQUEEZE

Dynamic compression for solo work, especially electric guitar. It gives you that glassy tele/strat sound. A true classic.

PUMP

Make the COMP16 pump up the prime. A setting for making the compressor pump in a desirable way. This effect is good for snare drum to increase the length of the transient by bringing the signal up after the initial spike. Very contemporary.

Tamer

Tame that funky low end. Designed to help control low end transients. This setting is especially useful for Bass Guitar.

APPLICATION GUIDE QUICK START

1. Connect your COMP16 using one input jack (TS, TRS, or XLR) and one or more of the output jacks(TS, TRS, or XLR).

2. Select your preset. (Refer to the preset descriptions above. Remember that the Ratio, Attack and Release knobs are only active in Manual mode.)

3. Do not push the bypass button in.

4. Turn the Input knob all the way to -20 (counter-clockwise).

5. Set the Output knob on 0.

6. Slowly turn the Input knob up (clockwise) until the Gain Reduction meters begin to move. Continue to rotate the Input knob until the Gain Reduction meters read between - 5 and -7.

7. Adjust the Output knob to the desired output level.

You should now have a very natural sounding compressed signal. Of course you should experiment with the settings to suit your taste.

BASIC CONNECTIONS

The COMP16 can be hooked to another processor, such as the EQ3B or TubePre in a live or studio environment. Please note that a microphone can not be plugged directly into the COMP16. The microphone has to be preamplified first. The TubePre would be a perfect preamp in front of the COMP16. We do recommend that whenever possible, balanced cables be used. Examples of balanced cables would be XLR or TRS (Tip Ring Sleeve). A balanced cable is preferred because it generally has a greater level of noise rejection. In other words it is less susceptible to outside interference.

Use with a Console/Mixer Insert

The COMP16 can be connected to an insert point on a console (mixer) by using a TRS Y-cable. This cable is Y-shaped, has a single TRS jack on one end and two TS (Tips-Sleeve) jacks on the other end. The single end will look like a stereo connector jack. This end of the cable plugs into the insert jack on the mixer channel. The other ends of the cable plug into the input and output of the EQ3B. If the EQ3B does not work immediately, you may want to try changing the jacks that are plugged into the input and output of the unit.

BASIC OPERATING PROCEDURES

Setting Compression Amount

Your COMP16 was designed with a fixed threshold mode of operation. This differs from other compressors in the fact that there is no threshold control. This offers the unique ability to immediately hear the sometimes subtle differences between presets which each have unique threshold settings. In setting the compression amount, always begin with the Input control all the way counter-clockwise (-20dB), and slowly increase the input until the Gain Reduction meters begin to register the compression activity. The more you crank up the Input the more compression your signal will experience. Always pay close attention to the best judge of your sound, your ear. You should also frequently remove the compression from the signal using the Bypass button to listen to the changes in your sound. In modern recording practice, it is customary to adjust the Output control such that the Input and Output level are of equal amounts according to the Output/Gain Reduction meter. This gives you an equal level output so that you can switch processing in and out to compare difference.

COMP16 SPECIFICATIONS

Number of Channels: 1

Dynamic Range: >115dB

Signal to Noise Ratio: >95dB

Headroom: +22dBu

Frequency Response: 10Hz to 50kHz

Compression Ratio:1: 1 to 20:1

Compressor Attack Time: 001mS to 100mS

Compressor Release Time: 10mS to 500mS

XLR Input Impedance: 10kOhms

TRS Input Impedance: 10kOhms

XLR Output Impedance: 51Ohms

TRS Output Impedance: 51Ohms

THD + Noise: <005%

Input Gain: -20dB to +20dB

Output Gain: -20dB to +20dB

Compressor Metering Output Level, Gain Reduction

Internal Operating Level 0dBu = 0dB

Input Connectors, Tip Ring Sleeve, XLR

Output Connectors, Tip Ring Sleeve, XLR

Power SupplyExternal, Linear Supply

Power Requirements16VAC,1000 mA 20W

Weight:4lbs

Size:55X55X175

Categories: Manuals | PreSonus Manuals