User Manual

Processing

Manual Make-Up Gain

The “O Gain” knob allows you to manually adjust the makeup gain applied to the signal after the gain reduction

applied by the compressor. If the Auto Gain switch is off, this is the amount of makeup gain applied. If the Auto

Gain switch is on, then this parameter is a trim added to the internally computed makeup gain. The makeup

gain is enabled and disabled along with the rest of the compressor.

Compressor Character

Use the compressor character button to determine the overall dynamic characteristics of the compressor. There

are three “classic” ChannelStrip 2 settings to choose from:

• Smooth – appropriate for full mixes or single instruments that do not have big transients. Provides very

smooth compression with few artifacts, no distortion and limited transient control.

• Warm – the most versatile setting for the compressor. Balances transient control with audibility of the

compression. Appropriate for a wide range of signals including harmonic instruments with large tran-

sients (e.g. Plucked bass).

• Fast – provides significant transient control at the expense of transparency and added distortion. Appro-

priate for impulsive signals with significant transients. Supports very fast (e.g. 1 sample) gain reduction

attacks.

as well as a new algorithm for ChannelStrip 3:

• MIO – provides the compressor characteristics from the MIOStrip compressor that runs on our interfaces.

This compressor algorithm is very different from the other three. The MIO compressor generates its

gain reduction directly from the detector level. The Attack and Release parameters directly control the

measurement of the detector level. This allows the MIO compressor to function as a limiter as well as a

compressor and a leveling amplifier. The MIO compressor algorithm also supports an adjustable Knee.

In general, the MIO algorithm is more flexible and controllable than the other algorithms, and as a result,

we have made it the factory default for ChannelStrip 3.

Threshold Control

The “Thresh” knob controls the level at which the compressor begins to reduce the gain applied to the signal.

When the detector level is below the threshold level, no gain reduction is applied. As the detector level in-

creases above the threshold level, the gain is reduced as indicated by the knee diagram associated with the

compressor. The compressor knee is soft. The ratio increases as the difference between the detector level and

the threshold increases.

The compressor threshold level is also indicated by the red bar above the gate input meter. You can adjust the

threshold level using this indicator as well as by using the “Thresh” knob.

Ratio Control

The “Ratio” knob controls the ‘terminal’ ratio used to compute the gain reduction of the compressor. When

the ratio associated with the soft knee hits the ratio specified by the ratio knob, the knee ‘hardens’ and remains

at the same constant ratio. If you set the ratio to 1000:1 the compressor will have a soft knee for all input levels

and thresholds. This makes the compressor work like a classic all tube limiter/compressor.

Attack Control

The “Attack” knob allows you to adjust how quickly the gain reduction is increases when the detector level

goes above the threshold level. This control is calibrated in milliseconds and values range from 0 to 500 ms.

The compressor has an 8 sample look-ahead buffer that allows it to have an “instant attack” when you set the

attack time to 0. Fast attack times will control the transients of impulsive sounds. Use longer attack times to

let the transients through but control the sustains.