Limit the volume of a track to avoid spikes (DSP chain)

(Raul (ulneiz)) #1

What would be the cleanest way to limit the volume of a track so that the instrument did not exceed the highest volume set, without the final sound of the track (its texture) changing too much?

That is, only recotar the highest peaks without influencing the rest of the sound along the track, with the condition that the resulting sound is as close to the real as possible.

What concrete configuration in the track’s DSP (Dynamics Devices) should I use?

(Zer0 Fly) #2

It depends on the type of sound. You could use either limiting/compression, or a soft clipper, or a combination of both. Compression/limiting can be used to either push down longer loud passages, or to radically chop short peaks, depending on the sound sometimes you might want a combination of both (first adjust long-term dynamics toning down louder passages, then chopping the short peaks with a limiter). All needs to be fine tuned to the actual sound and its characteristics. Percussive attack peaks are often easy to fix (limiter to chop them off, or soft clipping with threshold), while slowly swelling or bassy sounds might need a different approach to sound clean. Soft clipper won’t change dynamics, but add subtle distortion.

Sometimes with recorded audio or flaky instruments one might be tempted to just render the audio track and adjust the peaks in audio editor with volume curve. Or mabye use a lookahead dynamics device.

If its really just short percussive peaks, I tend to use the compressor device, ratio to limit, attack to shortest and also a short release of only like 5-25ms, and then set threshold so it will only affect the peaks. It will add a little clicky to the peaks, but if they are short/percussive anyways it mostly doesn’t matter. Look into the compressor devices for “leveler” presets for long term adjustment, and “limiting” presets for chopping short peaks.

(Raul (ulneiz)) #3

I think I’ll have to do a lot of testing here. With the percussion I do not usually have problems, they are serious sounds and if the body of the sound changes a little it is possible to correct it a bit by equalizing.

where I have doubts is in medium or high-pitched instruments, which can release short concrete peaks due to Round Robin or similar. I’m talking within orchestral music.

The issue is to stop those spikes without the body of the sound changing, and achieve it from the DSP of the track. I do not know what DSP device should use and what specific configuration should be set.

(Zer0 Fly) #4

As said a compressor in “limiter” mode, that is high (limit) ratio, no attack and short release, will chop off peaks that are above threshold, the short release will let the level return quickly for the body of the sound to have no degrading. Maximiser is also an option, not boosting and just letting it take care of peaks. Just make sure the threshold is catching the spikes, but is higher than the body of sound would produce. You might need a scope plugin with freeze option, or render the results, to make sure you have set things right. Another compressor in “leveler” mode (slow attack/release, low threshold) before the spike chopper can take care of dense passages tripping the chopper by ducking them down. It will let u loose a bit of the energy of dense passages though, sometimes a wanted effect, sometimes not so (orchestral). But it will even out the spike chopper’s response.

Ultimately fixing the instruments/samples so they won’t produce any unwanted funky peaks should be the best solution

(Raul (ulneiz)) #5

I think my particular problem is exactly this. It is possible that it exceeded this level (even if it was a little), therefore, part of the sound that has no peak was damaged. The result is that I noticed some change in the whole track, when it really was not what I wanted.

This becomes somewhat complicated when the instrument does not always reach the same volume, it is more like a roller coaster or depends a lot on the speed of pulsation along with its own effects to humanize them. In some VSTi of musical instruments it is quite complicated to control all this. What happens is that, due to these peaks, you are forced to lower the overall volume of the master losing strength throughout the song. With these little tricks you can get more distance between the instruments, and thus it is possible to put more details, more sound space.

Thanks for all the notes! Now I think I will know how to detect this particular problem.

(ffx) #6

I think - but don’t know exactly - that Renoise actually can handle float values higher/lower than 1/-1 without any digital clipping. So even if your peak meter exceeds its range, there still won’t any clipping occur, except on output and maybe some thrird party plugins which use hardclipping to ensure its algorithms to work properly.

(system) closed #7

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