Playing with compression

[Trshot]

I want to start using compression to clean things up. I've always mixed without it (only my band) with good results but now want to take advantage of another tool.

Some quick tips would be nice like, All instruments and vox in FOH, MON or both? Pre DSP or pre Fader in mons? Are the presets just a starting point and/or set it and forget it on any particular input?

[gerenm63]

I usually use it only on vocals, selected drums, and sometimes bass guitar. Settings vary widely, depending on the performer, mic being used and input gain settings, and the sound you're after. Sound on Sound ran a good article on using compression a few years back (http://www.soundonsound.com/sos/sep09/articles/compressionmadeeasy.htm). You're going to have to experiment to find the best settings for the particular gig.

For vocals, I tend to start at about a 4:1 compression ratio, and a threshold about -17.5db.
For kick drum, I tend to start at about 2:1 compression ratio, and a threshold about -30db.

If you want to setup quick, Mackie's compression presets are also good as starting points.

[Fluddman]

I routinely use compression on vocals in FOH but not for foldback. I mostly use pre DSP sends for foldbacksends. Compression on vocals in foldbacks can lead to feedback issues unless used very gently.

[Trshot]

I routinely use compression on vocals in FOH but not for foldback. I mostly use pre DSP sends for foldbacksends. Compression on vocals in foldbacks can lead to feedback issues unless used very gently.

Vocals only or instruments too?  Pre DSP will allow changes in fold backs only not FOH too correct?

[Fluddman]

I routinely use compression on vocals in FOH but not for foldback. I mostly use pre DSP sends for foldbacksends. Compression on vocals in foldbacks can lead to feedback issues unless used very gently.

Vocals only or instruments too?  Pre DSP will allow changes in fold backs only not FOH too correct?

Compression on instruments too? - Routinely on kick and bass, other instruments on an as need basis.

Pre DSP will allow changes in fold backs only not FOH too correct?  Pre DSP aux sends means that the processing you use for FOH will not apply to aux sends (On the DL this would be EQ and compression/gate). This works ok for me as I mainly have one vocal per aux send and I use the aux channel for EQ. 

Cheers

[Wynnd]

I do a lot of general PA work and it was the Preachers who got me using compression.  Those guys can go from a bare whisper to shouting in the same sentence!   Compression allowed me to bring up the whispering to levels everyone could understand and prevented the system from self destructing with the shouting.  I only use it on vocals where I need it.  I default to having it off.

[walterw]

i like it on for vocals, but definitely not in the auxes. (hell, before V2, i was splitting the mics into separate channels just to allow for comp'ed front vox and un-comp'ed monitors!)

4:1 seems to be the right zone for vocal smoothing, with fastest attack and release, and the threshold adjusted to where it kicks in just a little with normal singing and a lot only with loud singing.

some smoothing for bass can be cool, like 2:1; you shouldn't need it for guitars, the amp already creates a natural compression.

i'll never compress an output unless it's an IEM mix, in which case i want it to be limited, so it never kicks in at all at normal levels but at anything over that it slams down hard to preserve hearing.

[Wynnd]

Guitar amps only provide some natural compression on the bleeding edge.  This is where a 20 watt amp shines over anything more powerful.  Played a couple of times with a "got to run the amp at 11" guitarist.  Sound engineer had his guitar amp shut out of the PA and he was still too loud to hear even the vocals or anything else.  (If you recognize yourself, sorry I didn't tell you, but it was the reason I found somewhere else to be.)   His amp was only 125 watts  pushed into oblivion.  Great sound, but no help or hope for the band.  (His sound was so much more important than the band's.  Never was able to tell if the singer was worth a crap.)

[sam.spoons]

Guitar amps only provide some natural compression on the bleeding edge.  This is where a 20 watt amp shines over anything more powerful.

+1, I built an 18 Watt a couple of years ago and love it.

[Greg C.]

If the desk I'm working on has the capability, I tend to use combo of channel and group compression. For vocals, I'll use light compression on the channels, usually no more than 2:1. Then I'll bus those channels to a group and have a compressor inserted on that with a much harder squash (~6:1) but at a relatively high threshold to act as a limiter. The group compressor is awesome when you have a more than one vocalist and they all start singing at once. And it works well for someone that goes from soft to really loud. It really keeps things under control without having a lot of compression up front on the individual channels.

Bass always gets compression to smooth it out, usually between 2:1 and 3:1, medium threshold, fast attack and release. For drums, I tend to use group compression for toms, a group for kick/snare. Guitars get similar treatment to vocals - light compression on the channels, limiter on the bus they're assigned to. Horns and such I'll do the same unless I'm running out of groups.

[Trshot]

Thanks for the responses.....I'm VERY green on this subject

Greg C, since I'm working with the DL1608 and groups aren't yet available should I individually compress each input, I hear it's not good to compress the full mix (using DL's compresser on the main UI) at FOH.

I'm just using the presets on the DL. Are there any articles/videos to explain in depth, threshold, attack, release, ratio and gain, what each of them are used for and how to set them? I know attack and release are for when the mic is open and closing the signal but that's it.

[Wynnd]

Compression is a bit difficult to understand because there is so much that can be done with it.  On my Hartke 3500 amp, there's only one compression knob.  Simple?  I decided it's overly basic.  You are right that better units give you a lot of choices.  (Even some more than the DL1608.)  I don't think there's a single right way to do it.  I do use output compression on L/R when running on the bleeding edge of my equipment as additional way of not having to recone any speakers.  There are times when I'm running the system outdoors and it's easy to drive them harder than you think you are. 

I've only run gates on kick drums, but I think I might have a good use when doing a panel discussion.  (Hadn't really given that much thought before.)  Might also be a good choice for live theater.  (Something else I do.)

[Trshot]

Wynnd, I thought I've read a post from Greg C stating too much compression can in fact overheat  the speaker coil causing early failure. That's why I'd like to learn before I burn!! 



I use gates on all my mic's....

[Wynnd]

While my current FOH speakers are powered, I still have a few that aren't.  I've got some EV SX-100s that are rated 200 watts RMS.  I don't run them with 800 watts and heavy signal processing.  Just because you can, doesn't make it a good idea.  So I run at continuous output levels.  And the few times in the past that I didn't, it has cost me money.  I've got a cheap streak and don't really have a bunch of money to be throwing away.  I'm betting that I've fried fewer speakers than most.  (One horn driver, two 15" drivers in my entire life.  I also had one that the magnet fell off when the cabinet fell off my hand truck.  I currently own 8 x 15" and 4 horns for unpowered PA mains.  Also, 6 monitor type speakers with 12" drivers and horns.  A 760 and 825 Leslie, Kustom 250 guitar amp with 2x15" and a horn, Ampeg Portaflex......)   There is some more, but that is the bulk of what I've got without getting into instruments.