Wednesday, October 14, 2009

qpaeq dynamic band subdivision

So heres a slick little feature to qpaeq you aren't likely to find in any other equalizer out there... simply widen the window and watch the magic happen.

Normal - this is the default number of bands available in most equalizers

A little more...

a little bit mooore...

and here's the widest I've ever made it

Notice that this still all has an octave feel to it. You get diminishing returns with that - all you've got to do is change the DEFAULT_FREQS in the though, preferably to something linear. I'll make a linear bands an option in the future (along with the default of octaves) - it's useful for my own purposes as I explain below.

Why did I do this? Elementary my dear Watson - hand crafted notch filters, that's why! I've got a bunch of songs with horrible noise in them that I can never find the frequency the noise belongs to - this makes it only a few minute ordeal and I've gotten results much better than audacity's stuff in less time. Oh and it just looks cool - go get qpaeq and try it out - it's nice and interactive while you stretch and shrink.

One of these days I'll try and record filtered audio (not too hard thanks to pulseaudio and monitors) to show people the difference equalization can make.

Oh, btw - I'm finally in pulseaudio mainline. You can also get qpaeq in releasish form here:


  1. thanks a lot but i can't execute qpeq

  2. Hi, I am trying to run your eq app under default Ubuntu 10.04. I did install the python libraries you mention in the readme. This is the last line I see when I run your script:
    dbus.exceptions.DBusException: org.freedesktop.DBus.Error.ServiceUnknown: The name org.PulseAudio1 was not provided by any .service files

    I would really love to have a system wide EQ in Ubuntu so I am really interested in getting this running.



  3. Hi

    I'm trying to compile under fedora12.
    It compiles but then it wants to install

    Under fedora12, there is already /usr/lib/

    How do you make it compile against current puseaudio version?