http://audioproc.ca/index.php?page=P_AudioProc
Get that stuff if you have Winamp. I am using it right now and my god does it sound good. It has every bell and whistle you can imagine.
$40 after the 15-day trial is up, not a bad price at all if it functions well. I think StereoTool costs more than that.
One thing I notice about these processor softwares is that most seem to concentrate on high loudness levels out of the box, if you want something lower, you have to undo the default presets that were put in.
Breakaway does have Reference, Reference Classical and Reference Jazz that are quieter presets, and then 20 more that are high power. Sonos 4 and Stereotool are loaded with so many sections and bands, and can be hard to adjust.
I'd like to see a processor that focused on high fidelity and a classy presentation all around, the opposite of the crush 'em all philosophy of the others.
At least AudioProc seems to give you all of the control to do what you want, though it doesn't look to be in active development at this time.