Ableton Forum

Quick question. How come the gain reduction needle seems more responsive at lower ratios? At a ratio of 2 you can get the needle to pump easier, but at 4 it barely moves...Is this how an SSL behaves?

I don't know if it's a ssl design, but yeah, the 2:1 ratio strangely compresses more than the others. But if it would be by design that would be mentioned in the manual, and of course it's not.

just an in because I would like to hear the answer

the glue compressor applies a softer knee at lower ratios and a harder knee at higher ratios. it may be that the softer knee at 2:1 is making a given threshold more responsive to input levels, as a soft knee essentially widens the threshold to respond to a range of input levels, as opposed to a fixed input level under a hard knee.

There's also the fact that, at a lower compression ratio, the needle should move more because it's compressing through a greater range. Imagine that you have a signal that ranges from 0 to 20dB over your threshold - at a ratio of 2:1, the needle will be swinging over a range of 10 dB. At a ratio of 4:1, it will only swing over a range of 5 dB. Even though at 4:1 the needle will probably overall be more deflected from it's zero point, it will only move 1/2 as far as if the ratio was 2:1.