[LAU] rumble, motor-like sound. What frequency to set notch filter?

[Brad Fuller]

millward wrote:
> I'm trying ot clean up a WAV file that has a low sounding rumble, motor-like 
> sound, sort of up and down.  It's lower than the bass line. I'm finding this
> hard to describe in words.  I'm using the Gnome Wave Cleaner and its got
> a notch filter but I don't know what frequency to set it for. I do know people
> hear from about 20 Hz to 20,000 Hz, on a good day, so would maybe 50 Hz
> to 100 Hz would be a good start?
>   
"up and down" sounds dynamic, so you either need a wider range or 
several. The best way is empirical: try a wide range and a deep cut of 
where you believe the sound to be worst. After that, adjust it narrower 
and listen for the offending sound and also move the center freq around 
until you hit it. Then experiment with the deepness until you get it to 
where you are happy with the compromise (compromise because you are 
affecting the sound of the program, of course.)


-- 
brad fuller
 http://www.Sonaural.com/
 +1 (408) 799-6124