I don't know how CPU-efficient it really is though, and that seems to be Ted's main concern.
My only annoyance with it is that (AFAIK) there still isn't a 64b version of it, though that problem is so common on windows it's hardly worth mentioning.
I miss Audion, from the folks at Panic (makers of Coda & Transmit):
https://web.archive.org/web/20120524030742/http://www.panic....
It had a similar spirit to Winamp, so much that AOL/Nullsoft looked into acquiring them. As did Apple before iTunes existed, as documented in The True Story Of Audion:
It's ancient software pretty much, written to be efficient on computers several generations back; should be fine as long as it hasn't had any major rewrites since then.
foobar is pretty efficient. Here it handles MP3 decoding and spectrogram visualization with only a few percent of a CPU.
Nowadays I listen to music off my phone, and on that platform BlackPlayer is as close to perfect as a music player gets.