Which compressor plugin (XP system) for LIVE recording
 

Just wondering which (under $400) plugin compressor (vst, direct-x, etc.) you guys recommend for live recording. Generally for music, and sometimes for FX and vocal recording. Note it is under windows xp and I am not certain which app I will use yet. But since they tend to have similar features I am not concerned about that (ie cakewalk vs cubase vs tracktion, etc.)

iZotope or WAVES in that price range. For a few more bucks, I'd jump on the Universal Audio wagon, because their tools are incredible sounding. iZotope gives the best bang for the buck, IMO, WAVES has a broader offering, and Universal Audio is just exactly the old stuff in software form, and is wonderful to work with.

Thanks Spot. BTW, do you happen to remember the name of the depth of field adapter you were using for you NYC presentation with the Sony HDV cam (cost about $500)?

you bet! It's the Red Rock Micro 35.

I may be misreading what you're saying here but a software compressor isn't going to have any effect on your "live recording" levels. Software compressors are used for mixing audio signals after they've been recorded. A software compressor will have no effect on any thing pre converter. What you'll need is a hardware compressor. The signal chain would look something like this. Mic-Preamp-compressor-Analog/Digital converter (sound card). If I have misread what you've said just ignore me. :-)

The RNC compressor sounds pretty good if you're looking for a hardware limiter/compressor for recording.
prorec.com has a review of it

Thanks guys, that was a question in my mind. Originally I started out getting either the focusrite twin trak pro or Joemeek's twinq (hence the price point), but then I thought it best to ask if I could accomplish the same thing via software. Apparently I can't co so currently. Oh Well, back to the hardware:-).

One more thing, and maybe this is a not too useful a point, but then maybe it explains Spot's answer. What I was mainly concerned about was not what happens pre converter, but rather what can be done between conversion (sound card) and recording (to hard drive). So the manipulating I am trying to accomplish exists after the sound has hit the board and has been converted by the sound card but before recording to the hard drive. In a live performance which is being recorded to hard drive by some program like tracktion or cubase, I want to be able to apply a compressor in that space right before it is recorded to the hard drive. This may simply be my misunderstanding of how these systems work, but I am assuming that if I can get a clean sound through a quality sound card, then there should be no reason why I shouldn't be able manipulate that sound via software compression (or eq or limiter, etc.) and get the same or similar result as I would get if I had applied a hardware solution pre conversion.

This stuff can be a little tricky to wrap the head around. What ends up happening is there is no middle stage between the sound card and the hard disk. You mentioned the idea of getting good audio into the computer and that's the point of the hardware compressor. They're used to keep the recording source at a level that doesn't overload the converter resulting in clipping. If you get clipping while recording no cmpressor post converter will help you. If you are recording with a 24 bit sound card and you have set the levels well, you won't need the compressor pre sound card. But many will use a compressor for insurance purposes. They will adjust it only to squish any unexpected high levels. So basically, you need to worry about how hot the levels are at the converter stage. If the levels are fine at that point, you can compress and EQ to get the sound you want after the fact and if you don't like what you hear, hit the "undo". :-)

And I use SONAR by the way.

From what I know:
A hardware compressor can increase the dynamic range of your sound card, whereas a software compressor cannot.

Suppose you're recording a strings orchestra, which are typically pretty quiet. At the end, people are going to applause and that typically has a high peak loudness. If you're riding the gain so that the orchestra is hitting around -12/20dBFS, the applause can get clipped. If you want that sound, then the clipping will make the applause sound pretty bad.
Some music pieces have extreme dynamics, which is another case where a compressor can come in handy.

A hardware compressor lowers/limits the signal before it hits your soundcard's A-->D converters. Software compressors obviously can't do this.

However, a software compressor can definitely come in handy when you're mastering your tracks. The extreme dynamics in some types of music may be totally lost on your intended audience. People may be listening to the track with lots of background noise (this is the main problem), and consumer audio equipment can't reproduce that great a dynamic range unless you know they're on headphones.

2- If the S/N ratio in your audio chain is really low, you might be able to record with very conservative levels and raise the volume in post, adding compression.

I haven't tried this myself, but I can't see why it wouldn't work.
A normal hardware limiter/compressor will give ~6dB of extra recording headroom while staying pretty transparent (as in, you can't really hear the compression).
A limiter/compressor with a smooth/soft knee function (i.e. RNC compressor sounds like software compressors with soft knees) will give maybe 12dB of extra headroom while staying pretty transparent.
Above that, the compressor will give you distortion. Whereas if you didn't use a compressor, you'd get clipping (which is worse).

These are really rough ballpark figures and highly subjective, so don't hold me to those. But maybe that'll help give you an idea of what a compressor would do for you. It may be that investing in a better sound card/interface first would give you more headroom to work with.


2- The RNC compressor is not necessarily the cheapest, although it's only $200.

You could also check out the various compressors recommended by the Harmony-Central forums ( http://acapella.harmony-central.com/...hreadid=227171 ):
I haven't used any of those other compressors, so your mileage may vary.

Thanks guys, that info does help to clarify matters. a couple more thing: If I am multi-channel audio is it necessary to add a compressor to each channel or does it simply depend on the different sources being recorded and the likelihood of any of them being clipped (ie. percussion vs horn vs voice, etc)? On a video/audio related theme, I assume loud special effects in a multi sound environment would require similar treatment.

You'll want a compressor for each individual mic, unless you're stereo, in which case you'll usually want a linked compressor so you don't run into timing issues.

Maybe it would help if you could give us an example of a likely recording scenario.

As for the hardware/software issue, I agree that a hardware compressor is helpful for preventing digital clipping, provided that your digital recorder/soundcard has a low signal-to-noise ratio. I prefer to use software plugins for adjusting the sound after recording it, as there is an "Undo" button that way.

For multi-channel recording, a [hardware] compressor of some kind would be required for each channel. I personally like the dbx 166XL -- dual channel for about $200. I wish the noise gate on it was a bit more subtle, but the compression section works well.

I've done 24-bit recordings with no hardware compression applied, with good results in post. Yes, it does depend on the nature of the source. Watching your VU meters will give you a good idea of a vocalist's/instrument's range. 'Just be careful not to apply too much compression, which can result in a "pumping" or "breathing" effect.

The other "gotcha" with compression is when you apply it to a final mix. If one particular instrument is too loud, the compressor will see that and lower the whole mix, potentially surpressing it to the point that the troublesome instrument is now playing solo! This is an extreme case, but I've seen it happen.

This is all stuff I've learned from experience. That said, I always welcome any corrections by the more seasoned members of this board, as I know I've got a lot to learn!

Darrell, I also use Sonar! ('just received v4 Producer Edition -- can't wait to try it out!)

DSE, you beat me to it! I thoroughly agree.

My compressor has a link mode, but I didn't know it could cause timing issues. I thought that made it sum the inputs and ride the two channels with equal amounts of compression.

I should have been more clear. If you have a stereo signal, and you feed it to a 2 channel compressor, and don't link the two channels, it can cause timing issues due to the same sound striking both mics at slightly different times. Linking is generally done with stereo feeds. But like anything audio, there are no rules, and each scenario must be examined on its own merit.