I dunno, but I've wondered the same thing about the Sirius programming I get with my Dish satellite service. And also, what bit rates are being used? I bet we'd all be surprised at how low those are! I'm guessing around 64kb/s.

I've attended a few XM press conferences and they always get kind of vague when this question is asked. However, I seemed to remember reading something about this in Stereophile and went back through my archives.

What I was remembering was something I'd written in our eNewsletter (http://www.stereophile.com/images/newsletter/1204stph.html):

"JA and JI attended 'Mastering for Low-Bit-Rate Perceptual Codecs,' a workshop at the 117th AES Convention in November, which included Tony Masiello, XM's senior vice president of operations. According to his presentation, as reported by Stereophile's editor, a stereo channel on a DAB network has, at best, a bit budget of just 64kbps. (This is not a figure XM or Masiello gives out, but divide the overall satellite bandwidth by the number of program channels and that's what you get.) In order to encode music to fit that budget without sounding terrible, XM begins with the CD data

Dear Wes,
My understanding is that some XM and Sirius tuners have digital outputs. Would you happen to know if these output a standard (upconverted) SPDIF 44.1K stream to interface to DACS?

Re: an unrelated item, some time back I noticed that the McCormack DNA-500 was in you list of associated components and then disappeared. As a fan of Steve's products, I was curious to know if and when you might review it.

Thanks,
Buelligan