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Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Mon Jun 15, 2020 9:57 am
by mayo
Spogg wrote:I was thinking about this all wrong!
If you have a loud signal it can’t be quiet
at the same time (unless Schrödinger was involved).
So, you use an envelope follower of your choosing (peak/rms etc.) and the side chain value created is used to route the incoming signal through one effect channel or the other.
The routing (multiplexing in effect) should be “soft” to avoid sudden shifts. So at say -12dB channel A gets the whole signal and at say -6dB channel B gets the whole signal. In between those crossover levels the signal is shared, so at -9dB both channels get an equal amount of the signal.
At the end of the 2 processing chains the signal is combined.
I think that approach would work and be quite useful and potentially interesting.
Cheers
Spogg
yes this sounds good, nice idea, do you think you can make also schematics for that? of course if you are interested in this project and find it usefull in your work /and have some free time. I think this processing can be very usefull in making plugins / processing audio, because usually you want to process just peaks (in mixing/mastering) not to distort or shape whole signal (most techniques like saturation, compression, limiting want just to remove sharp digital peaks, round them etc.)
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Mon Jun 15, 2020 11:47 am
by Spogg
Since I don’t make actual music I wouldn’t personally have a use for it. Plus I’m really busy with several projects at the moment.
However, if nobody else wants to step up, I’ll put it on my to-do list because it does kind of interest me.
Reverb/echo on just the loud parts?
Cheers
Spogg
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Mon Jun 15, 2020 4:16 pm
by k brown
Pretty sure your idea is how multiband compressors work. Could use it for compression, EQ, whatever.
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Mon Jun 15, 2020 4:27 pm
by tulamide
Spogg wrote:Reverb/echo on just the loud parts?
If given the opportunity, I'd put them on the quieter parts!
In general, I see the possibilities with this technique (could fully imagine it after MichaelBenjamin talked about sidechaining), but can't help.
Kevin, multiband compressors work by splitting the signal into frequency bands, independend on their amplitude level.
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Tue Jun 16, 2020 7:35 am
by Spogg
I’m getting progressively more interested in this idea…
Different filtering on the loud parts and quiet parts?
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Tue Jun 16, 2020 1:17 pm
by trogluddite
Once you have a regular gate, most of the hard work is done, surely? A gate with envelope-time control already generates a "gain" signal with which to multiply the source. All you need to get the "below threshold" part is the opposite gain - maximum when the gate is "closed" and minimum when "open" - i.e.
signal * (1.0 - gain).
Here a very quick modification of the stock gate which should give us a starting point...
That only a first blush, of course. Two possible improvements come immediately to mind...
- More control over the "crossfade" - maybe this "linear" crossfade would not be ideal in all cases?
- "Look ahead" to ensure that very fast transients are handled correctly at short attack times.
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Mon Jun 22, 2020 2:06 pm
by mayo
trogluddite wrote:Once you have a regular gate, most of the hard work is done, surely? A gate with envelope-time control already generates a "gain" signal with which to multiply the source. All you need to get the "below threshold" part is the opposite gain - maximum when the gate is "closed" and minimum when "open" - i.e.
signal * (1.0 - gain).
Here a very quick modification of the stock gate which should give us a starting point...
hi_lo_splitter.fsm
That only a first blush, of course. Two possible improvements come immediately to mind...
- More control over the "crossfade" - maybe this "linear" crossfade would not be ideal in all cases?
- "Look ahead" to ensure that very fast transients are handled correctly at short attack times.
Thank you very much, I was experimenting with simmilar method using gate and phase inverse, with little bit different sound results.
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Mon Jun 22, 2020 2:08 pm
by mayo
some of you asked what is use of this splitter: many uses - for example some analog devices works different in low signal and dirrefent for peaks/transients (like tape etc.) so for emulation analog hardware, tapes, etc. to use different type of saturation for lower signal and for peaks.
Re: DSP: possible to split audio to 2 volume levels? peaks a
Posted: Sun Jun 28, 2020 12:08 pm
by mayo
https://oeksound.com/plugins/spiff/this is perfect example for what transient / below splitter is perfect for
but it is splitting transients part somehow better than our techniques , more cleaner, more detailed
do you have idea how they made it?