Tool for removing accompaniment on recordings

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skooter500
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Tool for removing accompaniment on recordings

Post by skooter500 »

Guys
I thought you might be interested in trying out a new software tool developed by some of my colleagues in the audio research group in DIT. Its called Riffstation and it has a whole load of audio processing tools such as chord analysis, time and pitch modification etc., but most interestingly for me, it can be used to isolate the different instruments in a recording. Ive used it to remove piano and guitar accompaniment for example so you can isolate the melody instrument for tune learning.
You can also slow down and transpose the instrument. Its rather cool and 100% developed in Ireland!
I've made a YouTube video demo here:
http://www.youtube.com/watch?v=hrcqhemICdI
And you can download a free trial from their website to try it out for yourself:
http://riffstation.com/
Let me know how you get what you think...
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MTGuru
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Re: Tool for removing accompaniment on recordings

Post by MTGuru »

Interesting, Bryan. So it does more than a simple phase reversal? For example, can it remove the guitar and leave the piano? And regardless of where they're located in the stereo image?
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s1m0n
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Re: Tool for removing accompaniment on recordings

Post by s1m0n »

That's pretty interesting. In that central graph you're working on, what do the x and y axes represent? The vertical axis might be amplitude, but I have no idea what the horizontal spectrum displays. Is it the spacial separation of the instruments in the room or in the mix? I suppose you can analyse differences in L-R volume and maybe even the relative signal lag reaching each mic to sort the stream of sound into constituent parts. Is that what you're doing? If not, I've no clue that might work.

The only other thing I could suggest is that for itm, it'd be nice to have GDAE fingering charts or (ideally) 4 assignable open string tunings. I didn't pay close enough attention - do the guitar settings only work in one tuning, or can you switch up between dadgad, std, etc?

Does this require stereo recordings? Will it work in mono, or at least with source music recorded with one crappy stereo mic?
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skooter500
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Re: Tool for removing accompaniment on recordings

Post by skooter500 »

TBH I dont know how it works, I didnt write it! It was developer by Dan Barry from the Audio Research Group. I know he has published papers on the algorithm, so Im sure you could look it up. It was licensed by Sony a few years ago for use in the Sing Star game to mute the singing from recordings. It does require a stereo recording I know and it uses the differences in how a particular instrument is distributed in the stereo mix to filter. It doesnt always work 100%, but when it does (as with the demos I used in my video) it is pretty amazing.
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Re: Tool for removing accompaniment on recordings

Post by Feadoggie »

Applications like the one mentioned above have been emerging from various corners of the industry over the last five or so years. I have little use for them as my personal work is mostly about creating and recording new material but there are a lot of folks out there ('musicians' that are not not themselves players of instruments) that live off of isolating and sampling existing parts and mashing them together to "create" new music. Since I have no need for such a tool, I have not looked into how they actually accomplish what they claim. I do know that they are not simply checking the stereo phase as simpler "vocal scrubbing" or karaoke programs and plugins have. There's a bit more to it than that. I do know that these tools are widely in use. I had thought by now that one of these would be offered as a free plugin to one of my DAW's so that I could play with it but, no, hasn't happened. I can see these tools being used as transcription aides.

Roland offers a product called R-Mix which appears to take a pre-recorded piece and use the tools to separate it out into tracks so that it looks like it may have when recorded, isolating each part, and allowing you to edit you heart out either remixing or pirating parts, changing tempo, key, etc. It costs about $200 US. You can look at a demo of R-Mix here. The underlying software components are now appearing in several Roland offerings (sampling workstations) so I continue to assume tools like these will be embedded in DAW's in the near future just as their V-Vocal software has.

Fascinating stuff.

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brad maloney
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Re: Tool for removing accompaniment on recordings

Post by brad maloney »

Can we use it extract Coleman's dodgey piano players? :tomato:
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Re: Tool for removing accompaniment on recordings

Post by Feadoggie »

brad maloney wrote:Can we use it extract Coleman's dodgey piano players? :tomato:
Yes, it should work for that too. :lol:
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