Hey all. So I have been poking around with audio as I usually do, and I noticed that the pro channel PC76 compressor attack times are extremely short. at most 1.2 ms? wouldn't this kill every transient in the world? What is this useful for aside from maybe parallel compression?
 
Seems kind of odd for the "default" pro channel compressor to be so mean to audio.. so yes i mean we should just switch to the 4k (which is still pretty short - 30ms). but my question is why is it default?
 
thoughts?

elijahlucian
Hey all. So I have been poking around with audio as I usually do, and I noticed that the pro channel PC76 compressor attack times are extremely short. at most 1.2 ms? wouldn't this kill every transient in the world? What is this useful for aside from maybe parallel compression?

I don't understand how a short attack would "kill every transient in the world." The shorter the attack, the less the effect on the transient.

You sure about that Craig?
 
Surely the shorter the attack, the more the transient is clamped down?
 
You use a long attack to let it come through.
 
Or have I been doing it wrong for 20 years. That might explain a lot. 

Of course, you're right. My brain was thinking envelopes. I should probably not try to type in the middle of eating lunch 

Ah! Blame it on low blood sugar. I have the opposite problem......

I am curious about this as well and have wondered the same thing. That I why I use the bus compressor more often. However, a couple of thoughts come to mind.
 
1. The attack time doesn't necessarily mean the that full compression ratio is reached at this time. It is more of a slope. Think Xdb/attack time. That is it will change from no compression to Xdb of compression in the attack time which could be less that what would be applied if the attack time was say 0. So, depending on the design of the compressor the 'Xdb' could be smaller, say 3db/1.2ms, than a compressor designed with 10db/1.2ms.
 
2. A snare or acoustic guitar could have transient information within a millisecond or two but you would have to use your ears or analyze the effect of the compressor on the instrument to see how much it really does to it.
 
3. There are uses for a quick compressor is you are trying to level out the overall volume and not change the tone of the sound too much. A quick compressor would not let as many transients through and would compress the whole sound more evenly than one with a slow attack time. Of course threshold and release time play into this as well.
 
Just some thoughts.

The attack range is the same as the hardware its based on, the 1176. Which was always more a "character" compressor than a transparent one. I like it a lot (both the real thing and Cakewalk's emulation), but it's not suitable for everything. It's great as a parallel compressor, if you use the infinity mode.

To make up for my egregious carelessness in responding too reflexively, I thought I'd do some research. The hardware 1176LN attack times go from 20 microseconds to 800 microseconds, so I guess extending that to 1200 microseconds - while making the PC 76 not as much of an "emulation" - does give you a little more slack.
 
But also remember that with an 1176, the way you adjust compression is by slamming the input, so you're going to have a lot more signal being let through by that initial attack. I took a screen shot with 1.2 ms compression and a kick drum input signal of +3 dB or so (and the lowest possible ratio, 4:1); it's interesting. The top image is the compressed signal - note that it actually has a much more pronounced transient than the lower image, which is uncompressed. I think this is due to the input gain being left alone for 1.2 ms, so it gets a nice, big spike.
 

 

The attack knob on the 1176 is reversed, ie the shortest attack time when rotated fully clockwise. I presume it's the same on the PC76?

No, it's the other way round.