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Trying to find simple brickwall
If SAMPLEVALUE > X then SAMPLEVALUE = X
If SAMPLEVALUE < -X then SAMPLEVALUE = -X

Why can't I find something that can do this simple task? Anyone know of a plug-in that can? I'm running vintage Audition 3.0.1.
Project Leader of DDResampled

  • saratoga
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Trying to find simple brickwall
Reply #1
You mean a limiter?  Never used Audition, but almost everything has those.

Trying to find simple brickwall
Reply #2
From my experience a limiter is effectively like a dynamic normalizer. I'm looking to intentionally clip samples that go past a certain threshold, the more specific the better.
Project Leader of DDResampled

Trying to find simple brickwall
Reply #3
I'd like to add that this was possible in the old Goldwave's compressor but the level couldn't be set extremely precisely. The compressor in the newer Goldwave can't be a perfect brickwall; it deviates a few samples sometimes.
Project Leader of DDResampled

  • mjb2006
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Trying to find simple brickwall
Reply #4
It's not exactly elegant, but you can increase the amplitude by X amount to get the clipping, then save, close, reopen, and reduce amplitude by same amount.

  • Brand
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Trying to find simple brickwall
Reply #5
Maybe GClip (VST effect) does what you need.

  • C.R.Helmrich
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  • Developer
Trying to find simple brickwall
Reply #6
In Audition 1.x, you could use the Effects -> Special -> Distortion... tool to clip a signal. Don't know if that still exists in later versions. Anyway, to create a digital clipper, select the Flat (no distortion) preset, add one data point at e.g. -6dB input, -6dB output, and move the 0dB input, 0dB output point to 0dB input, -6dB output.

Chris
If I don't reply to your reply, it means I agree with you.

Trying to find simple brickwall
Reply #7
If SAMPLEVALUE > X then SAMPLEVALUE = X
If SAMPLEVALUE < -X then SAMPLEVALUE = -X

Why can't I find something that can do this simple task? Anyone know of a plug-in that can? I'm running vintage Audition 3.0.1.


If the signal is 16 bits then it will clip at +/- FS if you amplify it too much.

For example if you want to clip something at  FS -6 dB, just amplify it by 6 dB and then amplify it by -6 dB.

  • DVDdoug
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Trying to find simple brickwall
Reply #8
Quote
If the signal is 16 bits then it will clip at +/- FS if you amplify it too much.

For example if you want to clip something at FS -6 dB, just amplify it by 6 dB and then amplify it by -6 dB.
But, you might have to save as 16-bit WAV after amplifying by +6dB in order to get clipping.    Then re-open the file and reduce by 6dB.  (I don't use Audition, but most audio editors use floating-point internally, and they won't clip.)

If you want to work with actual sample values, rather than indirectly in dB, GoldWave's "Expression Evaluator" should be able to do it.  It can do simple conditional processing (if n > X...).  But the Expression Evaluator works in floating-point too, so assuming you have an integer file, you'd have to convert your target sample vlaue to floating-point.
  • Last Edit: 30 January, 2012, 08:54:57 PM by DVDdoug

Trying to find simple brickwall
Reply #9
The distorter seems to work differently than the way you're suggesting and I couldn't figure out a way to make it work this way. But with a combination of MKB's method and GClip I can achieve what I want. GClip only allows you to set whole percentages as the threshold, but does what I'm looking for therefore I can bring to level to be cutoff to 0db using math to back and forth while in 32-bit editing to keep the rest of the stream intact.

Thanks for the help!
Project Leader of DDResampled

Trying to find simple brickwall
Reply #10
The distorter seems to work differently than the way you're suggesting and I couldn't figure out a way to make it work this way. But with a combination of MKB's method and GClip I can achieve what I want. GClip only allows you to set whole percentages as the threshold, but does what I'm looking for therefore I can bring the level to be cutoff to 0db using math to back and forth while in 32-bit editing to keep the rest of the stream intact.

Thanks for the help!

I was looking around for info about Goldwave's expression editor but it's not something that's documented very well.
Project Leader of DDResampled

Trying to find simple brickwall
Reply #11
Quote
If the signal is 16 bits then it will clip at +/- FS if you amplify it too much.

For example if you want to clip something at FS -6 dB, just amplify it by 6 dB and then amplify it by -6 dB.
But, you might have to save as 16-bit WAV after amplifying by +6dB in order to get clipping.    Then re-open the file and reduce by 6dB.  (I don't use Audition, but most audio editors use floating-point internally, and they won't clip.)


No, it works exactly as I said in Audition which is what the OP said he was using.

Amazing how far people will go to push their preferences!

Trying to find simple brickwall
Reply #12
This came up again, and I wanted something more precise as changing volumes wasn't giving me unaltered results, so here's what I was able to do this time using the Goldwave Expression Editor:

(wave1(n)-x)*(wave1(n)>x)
and
(wave1(n)-x)*(wave1(n)<x)

These expressions will silence samples that aren't louder than "x" (0 is silence and 1 [or -1] is 0db) and allow the difference between x and the sample into the waveform if it is louder. The first expression is for the positive side and the bottom expression is for the negative side, and by invert mixing the results into the original stream the desired brick wall is attained. The level specified in the expression editor, though, doesn't show to be that exact level in Adobe Audition, albeit it's very close.
Project Leader of DDResampled

Trying to find simple brickwall
Reply #13

Hard limiting (process). I don't know if it will let you use specific binary values. When I use it it's in dB mode set to 0.1 dB below FS with gain boost set to 0. Basically it eliminates triggering the overload indicators.