compression distortion?

[Son of Bovril]

I'm playing through a DBX 160A and I had a DBX 166XL before and with both I noticed that when the compressor was working in hard knee mode, I got a bit of distortion added to my signal? It's not the attack or release settings, as I've tried really fast and slow settings and it happens with both, and it's not the bass, cause when I bypass the compressor it doesn't happen?

any ideas?

[TaySte_2000]

I was clipping my Rane when I ran it in my effects loop as I had a bit to much eq boosted and such, try turning down the effects loop if you can.

[Son of Bovril]

could be that, but i don't think so... it's got an input meter and it doesn't seem to be clipping?

[TaySte_2000]

Neither was mine

[JanusZarate]

Some compressors can add distortion or artifacts, and it has more to do with the compressor's design and the settings you use.

A few of Bongomania's compression links may be helpful to you on this issue. Take a look in his signature when you get a chance!

[bongomania]

Well, unfortunately I don't think the answer is in my FAQ page. The dbx units would only tend to distort if:
1) the input is hit with a hot signal peak
2) the limiter is at a low threshold (the dbx limiter is junk IME)
3) the attack or release are set too fast

So, try turning off the limiter and see if that helps.

Also, you might have the output of the dbx set higher than unity, which would result in distorting the amp it's plugged into.

[Son of Bovril]

Hey bongo, I did read through your FAQ page actually...

it only seems to happen when I hit the strings really hard and it switches from overeasy into hard compression (ie. orange to red light). the 160A has to attack and release settings and it has no limiter (I agree that the DBX limiter is junk)

could you also please explain the concept of unity gain to me?

[bongomania]

Unity gain is where the peak output level of your signal is the same whether your fx are engaged or bypassed. That way you do not accidentally overdrive whatever fx or amp is next in line.

Could your describe the distortion- is it a momentary click, a short buzz, an extended dirty grind, a "pop", a flutter, a glitch in the lows or highs, etc.?

[Son of Bovril]

ok! now I understand unity gain ;-)

the distortion is a gritty buzzy kind of distortion that appears only on the attack of the note when played hard and doesn't last very long

[figuredbass]

Originally Posted by Son of Bovril

I'm playing through a DBX 160A and I had a DBX 166XL before and with both I noticed that when the compressor was working in hard knee mode, I got a bit of distortion added to my signal? It's not the attack or release settings, as I've tried really fast and slow settings and it happens with both, and it's not the bass, cause when I bypass the compressor it doesn't happen?

any ideas?

I use a DBX 160X and am also familiar with the 166, so I can venture an idea of why this may be happening. When you use these compressors in soft-knee ("Over Easy"®) mode, the actual working threshold is much lower than in hard-knee mode for the same ratio and threshold control settings. This produces more overall compression, and therefore more gain reduction. With LESS gain reduction in hard-knee mode it is possible that on the louder attack transients the higher level is clipping a subsequent device in the signal path. I doubt the distortion is actually occuring inside the compressor itself, unless your input levels are extremely excessive. See if lowering the output gain control on the compressor(s) to unity (or even a few db below unity) solves the problem.

[Son of Bovril]

thanx figuredbass, I'll give it a try and see if it works out ;-)