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Old August 30th, 2009, 03:52 PM   #16
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And be aware that if you have multiple tracks of the same source you're trying to fatten, that simply adding a plugin to one track may cause delay because of the time it takes the audio to go to the plugin and back.
That's unlikely for compression, since simple compression has no inherent delay. (The attack and release settings look to the past, never the future.) EQ is another story. Filters are implemented with delays, scalings, and sums.

If worried about delays that your software might have in its implementation, run both tracks through the same type of compressor plug in - but only apply heavy compression to one. This all but guarantees sample accuracy.
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Old August 30th, 2009, 09:37 PM   #17
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Vegas has latency compensation. One thing Sony didn't screw up... yet anyway.
OT.. Ah, I remember my first Eventide 910, making perfectly good voices sound like Satan.
OT-2: Steve, If you come to NY, I'll buy ya dinner & drinks @ Mustang Harry's on 7th Ave. (three blocks South of MSG)
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Old August 30th, 2009, 09:50 PM   #18
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Vegas has latency compensation...
I use Vegas and have never heard any funny phasing when using plugins on doubled tracks. Apparently, they implemented it ...and it works. :)
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Old August 31st, 2009, 04:27 AM   #19
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Are we not getting a little 'blended' with techniques for singers here? As far as I'm concerned, we're talking about very different ways to do things. I'm hearing delays, merges, split or central panning, phase issues etc etc - all very critical for thickening up a weak singer, but we were talking about stereo for video. Since having voices constantly moving around in the stereo field to match pictures never works that well, and just sounds a bit 'fake', most of us take the subject audio as a centre mono source and surround it with stereo (or pseudo stereo) music and fx. If you need more punch to the artiste in vision, or VO, then compression is the best way, and this is usually all that's needed to let it cut through even a music heavy mix.

I've never thought about double tracking the forward sound from a camera mic, or a studio naration track for video. A decent voice artiste and a nice compressor will do for me. As mentioned, double tracking that introduces time delay means phase cancellation - that's the entire point, isn't it? Great for music, not so hot for video - unless it's video to track, as in pop videos.
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Old August 31st, 2009, 08:49 AM   #20
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Paul,

The doubling that I'm talking about is very heavy compression on one track and little or no compression on the other. I use this specifically for a powerful voice-over. As with all dialog, it should be centered. Done properly, there is no delay between tracks, and no phasing problems result.

The problem with straight compression is that you trade off fullness and dynamics. By the time you've really filled in the vowels, you've smashed the hard consonants. You can play with the attack, but that only helps the first consonant of each word. Middle consonants still get crushed.

Picture the original signal as sharp peaks around deep valleys, and the heavily compressed signal as high plains with small hills. By mixing the two, we get high plains (strong vowels) with sharp peaks (crisp, dynamic consonants). This is like filling the deep valley of the original signal with water, as compared to straight compression which is designed to file down the peaks.

Again, I use this for the big voice over, not typically for on-screen dialog. On the other hand, if you have an actor with a particularly thin voice, this might be a good trick.
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Old August 31st, 2009, 04:13 PM   #21
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The doubling that I'm talking about is very heavy compression on one track and little or no compression on the other.
This does nothing you should not be able to do with any good modern compressor suitable for professional use.

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Originally Posted by Jon Fairhurst View Post

The problem with straight compression is that you trade off fullness and dynamics. By the time you've really filled in the vowels, you've smashed the hard consonants. You can play with the attack, but that only helps the first consonant of each word. Middle consonants still get crushed.
Not with a decent compressor. The only places I have ever seen this problem are with cheap, poorly designed 'compressors' in cameras (which are really just meant to be levelers, not compressors), and the old 'suck and blow' compressors hobbyists used to make from a small lightbulb and photocell in the 1960s. Oh, and some stomp pedal guitar effects.

Even the really inexpensive compressors I have use dual time constants to avoid that kind of problem. Most nowadays use RMS level detectors which should never have that problem. Most use some kind of 'over easy' type curve as well, which also helps eliminate that sort of thing.

'Compressor' is kind of a loose term. I may use, as needed on a voice, leveling, compression, peak limiting, de-essing, and frequency-selective limiting/compression. I just pick the right one(s) for the job. If one unit does not have all the functions needed built in, I just add another that does in series, there is no need for a separate track. (And of course they do have to be adjusted for the material)

Combining two tracks the way you do is just the equivalent of following a slower time constant compressor with a a peak limiter or faster time constant compressor. Perhaps you just need a more flexible compressor. What are you using that has this problem?

-Mike
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Old August 31st, 2009, 04:50 PM   #22
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I'm using the Track Compressor that ships with Vegas. It's the standard deal: Ratio, Threshold, Attack, Release. Vegas also has "Wave Hammer", which is more for mastering than mixing, and while it's "smart", it's lacking in user controls.

I've also got the Isotope frequency selective compressor, which comes with Sound Forge 9. I can't use this in Vegas though - it's locked to SF9. It's great for really pumping up a final mix. I haven't tried it on a single voice.

I know there's higher end stuff out there, like Waves, but the track doubling technique is available for free from most any NLE or DAW.
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Old August 31st, 2009, 05:20 PM   #23
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I'm using the Track Compressor that ships with Vegas.
Ah. Well, this is why I still like actual hardware for certain important functions. With hardware, I get a manual with full specs and usually a schematic (on pro gear), and it was probably designed by an engineer that has some practical experience with audio.

With software, I have no idea how the thing works, whether is has any of the more useful design features (as I mentioned above), and may have been designed by a computer programmer who just looked up some algorythms and called it good...it was free...

I have no idea how well that compressor is designed, but you might look around for something better (maybe even free). I can tell you for certain that any software compressor I tried that had the artifacts you describe woud be thrown out here immediately. That has just not been acceptable performance in a compressor for the last 50 years or so. ;-)

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I know there's higher end stuff out there, like Waves, but the track doubling technique is available for free from most any NLE or DAW.
Can't you just add two instances of the compressor on the same track, and adjust them as you would for the two track approach? (I have never used Vegas) I don't see any need of two tracks. This should actually work slightly better, because following the slow compressor with the faster one should give you a slightly more consistent peak to average ratio.

There's no harm in two tracks, it just seems like a waste of time and adds one more track cluttering up things for no good purpose.

For what it is worth, 99 percent of the narration I have recorded over the years has used just one compressor, either a Urei LA-2 (stupidly expensive) or a dbx 266 (dirt cheap). And I never saw those problems with either of them.

-Mike
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