One of the bright promises of satellite radio when it first appeared was the potential for delivering outstanding sound quality. I'm a long-time XM subscriber, and initially it seemed as though this was a promise that was being kept.

When XM first arrived on the scene, it was common to talk about "near CD-quality sound." I often enjoyed showing off my car XM system to friends, demonstrating the sound of the music channels versus a CD. And the quality was right about up there with a CD. I was hearing significantly more frequency extension than FM. The sound was very clear and detailed, with a nice sense of depth and presence.

But over time, to my ear, things began to change. It sounded like they were using more and more signal compression. While I still listened to music on XM, I drifted over increasingly to news programs and talk. The music just didn't sound good anymore -- it was flat, shallow, lifeless.

I was surprised back in August when I tuned in one of the music channels. "Strange," I said to myself, "the music sounds good today." Sure enough, I'd tuned into broadcasts being done with a new audio processor that XM promised would yield improved sound quality.

I'm pleased. Sound quality is definitely improved, with brighter highs and a good deal more depth and clarity. Score a hit for XM in my book. Has anybody else out there noticed a change for the better?