kick drum only (beat only)

Audacity 2.0.2
win7 x86
I may lack a fundamental understanding of sound waves which may make this impractical, but I’d like to get a beat track out of a song. This is for light sequencing, I have no interest in this “beat track” audio quality, I just want “sound events”. When I run a low pass filter (40hz, 30hz, whatever) against the song, even at the 48db dropoff, it still contains alot of the bass(instrument) from 50-200hz and I’d like for it to merely contain the kick drum itself. Is there a way to “cut” frequencies out altogether, as opposed to “reduce” them?

Nope.

Particularly at the low end, everything sounds the same. Everything, as you found out, sounds like a truck going by. Bass notes from most instruments tend to cluster around the note they’re playing, but the quality of the note is carried in the overtones and harmonics. Drums don’t work like that. Drums will kill you. They’re all harmonics and overtones. There’s no way to split apart a drum impact from the rest of the song because the sound of the impact is the same as a lot of the rest of the song.

I actually did this once. This is the spectrum of a bass piano note. G two or three octaves down. Because of the impact of the hammer on the string, look what happens to the spectrum.

http://kozco.com/tech/audacity/piano_G1.jpg

Try and split that away from the rest of the song. Drums are worse because there’s no note there. They are only a pile of harmonics and overtones.

You might be able to use some of the better Isolation software packages if the performance is in very good stereo.

–Extra Boy
http://www.kvraudio.com/get/1651.html
–Kn0ck0ut
http://www.freewebs.com/st3pan0va/

I don’t remember if they can both do that, but you can Google as well as I can.

If the show is in mono, that’s the end of the story.

Koz

@ kozikowski thanks for the links.