COMPRESSION

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Gale Andrews
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Re: COMPRESSION

Post by Gale Andrews » Sat May 16, 2015 8:01 am

steve wrote:
Gale Andrews wrote:Hang on. The very page you point to makes clear that the default (tied to the RMS choice) is downwards compression. Of course make-up to 0 dB is on by default.
Yes, makeup gain is on by default, so the net effect is that it compresses "upward".
As I wrote in an earlier post, upward compression is the "exact equivalent to compressing downward and then amplifying", which is exactly what Audacity is doing with the default settings.
I think many would expect that the peak/RMS choice is not tied to compression direction, but are you arguing that make-up gain should be off by default? The problem would then be that naive users would say "Help, my waveform has vanished".


Gale
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steve
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Re: COMPRESSION

Post by steve » Sat May 16, 2015 3:50 pm

Gale Andrews wrote:The problem would then be that naive users would say "Help, my waveform has vanished".
The waveform is hardly likely to "vanish" unless they also push the Threshold down to an extremely low level, but why does the threshold go so low anyway?
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whateverman
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Re: COMPRESSION

Post by whateverman » Thu Jul 30, 2015 9:51 am

Why also aren't their smaller ratios than 1.5 to 1? That's a real blunt tool.

steve
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Re: COMPRESSION

Post by steve » Thu Jul 30, 2015 1:25 pm

whateverman wrote:Why also aren't their smaller ratios than 1.5 to 1? That's a real blunt tool.
1.5 to 1 is a very small amount of compression, especially if you set the Threshold quite high. With a compression ratio of 1.5:1 and a high threshold, the effect will be so subtle that you can't hear the difference.
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whateverman
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Re: COMPRESSION

Post by whateverman » Thu Jul 30, 2015 8:55 pm

I'm gonna go with user error then, because I was working with an orchestral track with very wide dynamic range and I could not for the life of me get the built-in Compressor tool to avoid being over-aggressive at raising volume on the quiet parts. I didn't try very hard though, just ended up using Chris Capel's 1.2.6 plugin instead.

(I'm crossposting I know, but I really think it's relevant to both thread. Sorry mods.)

steve
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Re: COMPRESSION

Post by steve » Thu Jul 30, 2015 11:27 pm

whateverman wrote:I'm gonna go with user error then, because...
A good tip for using any dynamic range effect (compressors, limiters, et al), amplify (or normalize) up to 0 dB before you use the effect. Why? Because it makes it much easier to see and hear what the effect is doing. For example, if you normalize to 0 dB and then use the compressor with the "Threshold" set to -3 dB, then it is that top 3 dB that is compressed.

Having said that, I do agree to the extent that I think that the range of the compression ratio should start at 1:1.
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