Plainamp

Plainamp is a free, open source audio player for Microsoft Windows.More precisely it is a rewritten Winamp core (or plugin host) which means it relies on Winamp plugins heavily.

Features:

-Winamp plugin support (input, output, visualization, DSP and general purpose)
-Plugins can be manually loaded/unloaded during runtime
-Native output stacking — several output plugins at once
-Native vis stacking — several visual plugins at once
-Native DSP chaining — several effect plugins in a chain
-7 order modes