ANNOUNCE: Software equalizer for openmoko

[Russell Sears]

Andy Green wrote:
> That's pretty cool and short patch.  I always assumed that we need to
> lift the low end so much relative to high end to make a difference, that
> we would routinely clip even at medium volume levels.  Is it actually OK?

Thanks!  The gstreamer code is really clean; I thought it'd be a lot 
more work.

I have a set of in-ear sound isolating headphones that are *really* loud 
at default volume settings.

I figured I'd crank up the alsa volume, then lower the midrange and 
treble bands.  With the test program it seems to do an adequate job 
lowering the high frequencies, though I'll know for sure once I get 
mediaplayer to use it.

I've noticed that it clips and pops pretty severely if I set the gain 
positive on any of the equalizer channels, so it might be good to expose 
it as a passive equalizer that only makes the signal quieter.