introduced with Windows Vista.
Features:
- virtually unlimited number of filters (currently limited to 100 per channel for sanity)
- works on any number of channels
- very low latency, which makes it suited for interactive applications
- low cpu usage
Requirements:
- Windows Vista or later (currently only Windows 7, 8 and 8.1 have been tested)
- Sound card driver must support APOs (this includes most onboard sound drivers)
- The application must not bypass the system effect infrastructure
(possible by using special APIs like ASIO)
http://sourceforge.net/projects/equalizerapo/
Update 17. aug. 2014:
GUI for Equalizer APO i recommend EQ31GUI-2
Get EQ31GUI-2 here:
http://jiiteepee.tripod.com/eq31gui-2.html
