Spectral Subtraction

[declassified]

Hi everyone!

I'm looking for a spectral subtraction plugin that will analyze two audio signals through FFT, and then subtract one from the other. So if you imput identical signals, you get silence as a result.

I know about kn0ck0ut, but it doesn't support higher resolutions than 8192x8.

Is there a software that does this at resolutions of 16384 (or higher)? Obviously it doesn't have to be realtime , and standalone is fine, too (doesn't have to be VST).

Any suggestions would be much appreciated!

[The Chase]

Reafir

http://www.kvraudio.com/get.php?mode=show&id=2671

[Music Engineer]

I'm looking for a spectral subtraction plugin that will analyze two audio signals through FFT, and then subtract one from the other. So if you imput identical signals, you get silence as a result.

why go to the spectral domain instead of just doing the subtraction in the time domain straight away?

[quintosardo]

May be for a kind of "spectral ducking".

If he means subtracting the modulus of each bin it gets sense.

When a new instrument comes in the mix, its spectrum is subtracted from the overall mix to get some space (just an example).

I do this with Specter.

[declassified]

The reason I'm looking for this: I want to remix an old song (from 1972) for private purpose, where certain parts are panned left, right and in the centre. I can't subtract them in the time domain, because they are not exactly coherent, i.e. they don't cancel each other out.

I'm trying Reafir right now, but I can't figure out how to do this...I have to use "Subtract" mode, right?
What I have is a stereo signal with drums, bass and organ in centre, and guitar panned left. I want to subtract the right channel (drums, bass & organ) from the left one (drums, bass, organ & guitar), so only the guitar remains...

Thanks for any help

[Optomadic]

Have you tried Paul Harvey's amazing Extra Boy Pro? It works wonders on 'non center' signals.

http://www.paulrharvey.co.uk/elevayta/product13.htm

[pluginnow]

15 years later... , is there something like this?

[Ah_Dziz]

Metasynth should be able to do it (photosounder on Windows might work).

[sandandpaint]

spectralayers has exactly this function

[Robin Lobel]

15 years later... , is there something like this?

Have a look at SpectraLayers Imprint module, that's exactly what you need : https://download.steinberg.net/download ... print.html

[yellowmix]

15 years later... , is there something like this?

The original poster (and you, if that is your goal) is better off using an audio separation tool like UVR if they want to remix a song.

[pluginnow]

Okay, but in my case it would be a VST plugin and real-time (a small latency is acceptable).

[Smapti]

There's a number of these now. See eg: Neutron 5 unmask, Focusrite fast reveal, Techivation M-blender, Melda MSpectralDynamics. For a non-FFT solution see Trackspacer.

[DaveClark]

Hi all,

A technical clarification for those who may be misled by what has been posted in this thread.

Although there are tools that do a reasonable job of separating center from left/right signals, they are not as simple as the OP proposed, i.e. they don't simply subtract one spectrum from another. In fact, that is (as someone earlier implied) the same as doing it in the time domain because of the linearity property of Fourier transforms:

a*x(t) + b*y(t) in the time domain has the same effect as a*X(f) + b*Y(f) in the frequency domain. Here we could assign a = 1 and b = -1 so:

x(t) - y(t) in the time domain has the same effect as X(f) - Y(f) in the frequency domain.

There are many sources for properties of Fourier transforms, but here is the one I'm using:

Douglas F. Elliott and K. Ramamohan Rao. Fast Fourier Transforms: Algorithms, Analyses, and Applications. Academic Press, 1982, page 24.