Removing Background Music

Is there any way to remove the background music from this sound file?

Sound Effects + Background Music

I have the background music by itself:

Background Music

People have told me to Invert the BGM track and combine it with the other track to remove the common parts. But when i do that and combine them with Quick Mix, it doesn’t seem to do anything. What am i doing wrong?

It’s a lot harder than it seems because the conditions for this are very serious. The show must be in Stereo, the singer must be in the middle, etc. etc. In your case, the music must be surgically perfectly lifted from the original digital track and not just copied from a similar track you found on YouTube.

These are the usual tools…

Center Pan Remover (Voice Remover–Search the page for “Center Pan Remover”)

Voice Isolator (Opposite of Center Pan Remover)
Voice Trap
Extra Boy


Hey man, thanks for responding so quickly.

I actually made both of the tracks from a video game using an emulator, so they should be perfectly lined up. I just can’t believe that there isn’t some super easy way of importing both tracks and subtracting one from the other.

I’m searching for an illustration of how hard this is. Download the Left-Right-Mono track from here…

…and put it on a timeline. The last two tracks are in-phase and out of phase voice. If you magnify the waveforms several times you will find that the Left and Right tracks for “In Phase” are exactly the same, the waves go up and down exactly together. If you magnify the Out Of Phase voice (after “three”) you find the bouncing waves are exactly out of step. That’s the kind of accuracy you need to have. If you split track three (In Phase) up into two mono tracks, flipped one over and added them up, you would get a straight line. They would cancel out completely.

So it’s not good enough to press record twice on the same game performance, you have to slide one back and forth until the ultra teensy individual sound waves line up between the two performances. Then split, flip, and cancel.


Okay now that i’ve zoomed in enough, i do see that the two tracks seem to get gradually out of sync and actually end at different times. I have no idea why this would happen because i captured them for the exact same number of frames, but whatever.

I’ve spent the last hour trying to figure out a way to stretch the second track to the same exact length as the first track in Audacity, but the “Change Speed” and “Change Tempo” effects don’t seem to be accurate enough and i can’t figure out how to use the Nyquist Prompt whatsoever. I’d like to try giving the inversion thing one more shot after stretching the second track. Could you please help me figure out how to do that?

Also it turns out this particular game is really dumb and puts everything on the center, so the “Center Pan Remover” kills absolutely everything except one tiny bit of melody. It looks like i’m quickly running out of options.

There is a plug-in called “Kn0ck0ut” which can be used in Audacity to remove or isolate the centerpanned sound, even if tracks are not exactly in sync.
(you’ll need to install the VST bridge in the Audacity plug-in folder to use Kn0ck0ut and other VST effcts in Audacity)

Kn0ck0ut does have a slight glitch when used in Audacity though …


True. But the poster suggests his entire performance is center panned, so that may not work so good. We will add that tool to the list.

You have all the symptoms of a sloppy computer. All computers do not have ‘surgical computer accuracy.’ Some machines have master binary clock systems that drift over time and some cheap sound cards are legendary for recording and playing the same music at different speeds because of shortcuts in manufacture.


Kn0ck0ut did the job: here is a link to an mp3 of before and after background music removed, leaving effects …

The nature of this Kn0ck0ut job allowed me to cut out the silent glitches without these repairs being obvious, (I would still like to know how to prevent these silent glitches occurring with VST effects in Audacity, anybody ?)

I thought I’d have a go using just the tools built into Audacity 1.3
This is the first time I’ve tried this and I didn’t spend a lot of time on it so the results are not that brilliant, but give some indication of what can be done using just Noise removal, Equalizer and Amplify effects. Here is a link to an Ogg file that has Trebor’s “before and after” followed by an Audacity only “after”.

I’ve had another go , this time I have used compression, equalisation and echo on the Kn0cked0ut violent sound effects …

Boosting the isolated violent sound effects in the main frequency range of the organ music (50Hz - 1000 Hz) which was removed by Kn0ck0ut has improved matters.

Thank you sirs, i really appreciate the help. Right now i’m looking into a couple of alternative solutions for silencing the background music through the emulator. Unless some miracle happens, i’ll probably end up using one of the tracks you guys customized - whichever one ends up meshing the best with the music track my friend provides.

Hey i just wanted to thank you guys again for all the effort. Someone ended up coming through at the last minute with a way to silence the music in the game so the problem was solved but i appreciate everything anyway.

Here’s the final product if anyone’s curious: SF? Ryu Exhibition (Evo2k9+OHN8 Edition)

Filesize is a little big but it’s running at 640x480 59.94fps so i couldn’t do much about that, even with the fancy x264 codec.