Satellite radio quality?

[topspeed]

Dish recently added Sirius to it's programming, a no-cost addition that I thought was pretty cool. Anyway, I noticed while listening that the sound quality isn't very good. Everything seems pretty compressed with a dearth of dynamic range. I thought satellite radio was supposed to sound as good as cd? My experience is that it's a lot closer to MP3. Could it be my STB or is this as good as it's going to get?

[Woochifer]

I believe that with the Music Choice channels on Directv at least, they are broadcast at a sampling rate of 32 kHz, which is lower than the 44.1 used for CD audio. A few times when a song came up on the satellite that I had in my collection, I quickly did impromptu A/B comparisons, and the music channels on Directv do sound somewhat compressed in the dynamic range and a touch rolled off in the highs. As you noted, this is somewhat reminiscent of what MP3 does, although I don't know if any data compression is used on the audio signal or if the source file is an uncompressed full bandwidth source.

I know Sirius uses data compression on its satellite radio signal, but not sure if Dish does the same thing.

[topspeed]

Thanks Wooch,

Let me run an idea by you. Currently, my Dish STB is hooked-up analog via rca to my receiver. When I upgrade to a HD box at the end of the year, I plan on using a digital link. Do you think the Burr-Brown DAC's in the Denon will help (I really like what they do to CD playback in PureDirect mode) or is the data stream from Dish/Sirius already too compromised and/or compressed?

[Woochifer]

Thanks Wooch,

Let me run an idea by you. Currently, my Dish STB is hooked-up analog via rca to my receiver. When I upgrade to a HD box at the end of the year, I plan on using a digital link. Do you think the Burr-Brown DAC's in the Denon will help (I really like what they do to CD playback in PureDirect mode) or is the data stream from Dish/Sirius already too compromised and/or compressed?

I'm targeting the same upgrade at the end of the year. I have no idea whether or not it will help. It would think that it depends on how clean the signal is at each step along the way -- from the broadcast playback, to the satellite signal, to how the satellite receiver outputs the digital signal. My guess would be that at some point along that chain, it passes through some sort of signal alteration. Whether that be playing compressed files off a music server at the broadcast end (like a lot of radio stations do), downsampling the PCM bitstream before uplinking to the satellite, or using some kind of lossy compression at any other step, I doubt that what gets output through the satellite output will be the same 44.1/16 PCM signal as the original CD in the studio. But, even with all that, it certainly won't hurt to run the digital signal through a decent DAC. Ironically, some of the harsher recordings in my collection sound smoother when I hear them on the Directv music channels.

[Smokey]

I have Dishnetwork Receiver's (with fiber optic feed) and have compared sound quality of analog RCA output and Digital via receiver's DACs. The sound quality of analog RCA output tends to be slightly too boomy. But when I feed it thru the Receiver's DAC via fiber, there is more lineality in sound quality and less boomy.

As Wooch said, the bit stream is probably limited at the uplink, and definitely do not measure up to sound quality of good CD :)