KVR Audio

skybax · Post by **skybax** » Tue Feb 08, 2005 9:01 am

let's say I have two pieces of audio material, an a cappella-version of a track and the complete track.
I understand there is a trick to use the vocals-only track to remove the vocals in the complete track, bringing out only the instrumental part.

something to with phase (whatever that means) ?

I would really appreciate it if you could explain how to do it in Sound Forge.

stefancrs · Post by **stefancrs** » Tue Feb 08, 2005 9:10 am

Invert the acapella track and add it to the full track. If you're lucky, you can by adjusting the level of the inverted acapella track, get a clean instrumental.

This is very rare though, since quite often they apply compression etc in the mastering process.

Gwydi · Post by **Gwydi** » Tue Feb 08, 2005 9:15 am

In Sound Forge;

1. Load the two files

2. On one of them, do;
Edit - Select All
then
Edit - Copy

3. Switch to the other file, hit Ctrl-Home to put the cursor at the beginning

4. Edit - Paste Special - Mix

5. In the 'source' box, check 'Invert data' (make sure it's NOT selected in the 'destination' box

6. Hit OK.

That's it.

G.

skybax · Post by **skybax** » Tue Feb 08, 2005 9:36 am

thanks guys

actually what I'm trying to do is isolate the vocals from a track by cancelling out the instrumentals.

but looks like it's not going to happen since I can't find a source of the instruments that would be identical to the track (even in the track itself)

I wonder if there's a "smart" method that would automatically adjust the inexact source and use it as a guide to match the destination exactly?

Gwydi · Post by **Gwydi** » Tue Feb 08, 2005 9:55 am

skybax wrote:actually what I'm trying to do is isolate the vocals from a track by cancelling out the instrumentals.

You said you already have an a capella version ... ???

Morgaxx · Post by **Morgaxx** » Tue Feb 08, 2005 6:14 pm

Hello,

Regardless of the already having an a capella situation, you may want to look into KnOckOut...

"Kn0ck0ut is a VST plugin that takes two mono 44.1KHz inputs and spectrally subtracts one from the other. It can also retrieve centre-panned material from stereo input."

I havnt used it, but from a look at some of things it claims to do, you may find it usefull.

birrbits · Post by **birrbits** » Tue Feb 08, 2005 6:58 pm

Here is a cheap way (results will vary)
split the stereo wav into Left and Right mono wavs

To get the Right-side vocal:
Mix Right Mono + Left Inverted
Invert this and mix it with Right mono again

Repeat this for Left Vocal:
Mix Left Mono + Right Inverted
Invert this and mix it with Left mono again

Now convert/mix the left and right mono vocals to get a stereo vocal.

This approach assumes that only the vocal is mixed dead center....and there will probably be alot of additional noise....
good luck

st3pan0va · Post by **st3pan0va** » Tue Feb 15, 2005 10:05 pm

Morgaxx wrote:Regardless of the already having an a capella situation, you may want to look into KnOckOut...

good tip

extracting vocals when you only have an 'inexact' instrumental (so phase-cancel methods are out) is exactly what kn0ck0ut was originally intended for...eg if yr instrumental has been mp3'd, or if it's a section from another part of the track that you can loop etc

it'll never be perfect, but you can often get a usable result ...

the plugin is free from www.freewebs.com/st3pan0va

vocal removal trick