[linux-audio-user] Removing AC hum after the fact.

[Joel Roth]

On Mon, May 29, 2006 at 01:00:07PM +0100, Adam Sampson wrote:
> 
> If it's really mains hum, then you can probably just cut the
> frequencies below 130Hz or so.

I'm no expert, but if you still hear something after trying
this, you can experiment with extra filters at multiples
of 60Hz, i.e. 180Hz, 240Hz, 300Hz, 360Hz, etc. etc.

With speech you can be rather ruthless. But then to do all of the
harmonics up to 6000Hz, maybe you'd need a programmable
tool. I think you could chop the top off (above 6000Hz) and
no one would be the wiser. 

-- 
Joel Roth