You're confusing a couple of terms there. HD is an add-on to the existing FM bandwidth, and all you need to listen to these broadcasts is a (new) radio capable of receiving HD signals. Satellite radio (like XM or Sirius) is another matter, and requires a fee as well as an appropriate receiver.

I can't help you much on this one since I have neither. But you might want to clarify which service you're interested in.

Steve, thanks for clarifying the HD radio thing somewhat, but they are very expensive (2 to 4 hundred dollar range) and when I was listening to one at a high-end outlet I couldn't hear any difference, so are they tuning to FM stations that are not on the regular bandwidth? Also, I was wondering if satellite radio is worth a subscription fee and if the expensive radio is necessary to go along for more enjoyment.

The main benefits to HD radio, IMHO, are two: being able to send information like the song title and artist for display when the song is playing; and multicasting, which lets a station broadcast multiple formats on one frequency (for example, the local Snoozin' Oldies station has a Snoozin' 80s format on one of their multicast frequencies). The HD folks claim increased audio quality, too, but I'm of the opinion that, if you can't hear it, it doesn't matter.

As for satellite radio, many people find it worth the fee because it lets them listen to types of music which are difficult or impossible for them to find locally or when they travel. You might want to go to XM's or Sirius' Web sites to check out the variety of formats they offer. Guaranteed, it's more choice than you have wherever you live. But if you don't care about that much choice, you'll have to decide if you want to fork over the dough. It's kind of like cable packages -- if you won't watch the channels in the Premium package, it doesn't make sense to get it. I would say that satellite radio is worth the fee if you can listen to it a fair amount or if you really can't live without music in one particular format.

You don't need an HD radio to listen to XM or Sirius; nor is it likely to enhance your listening experience for satellite radio. You do need either a radio/car stereo/receiver/amp on which you can receive XM or Sirius signals (it will be so labeled if it can) or an add-on tuner; both companies sell several models of those. Keep in mind that XM and Sirius are trying to merge (government permitting) and that, eventually, one of those formats will die. That is likely several years away, though.

Thanks for a good overview...

We've had XM for about five or six years now. Both my wife and I love music, and I bought her an XM SkyFi for her birthday, along with the car kit and a boombox for her office. The SkyFi is an add-on receiver, about the size of a pack of cigarettes. You buy "cradles" for it that connect to either a car or a home stereo. The boombox has a built-in cradle. This allows you to have a cradle in your car, your boat, your motorcycle (yep, I know a couple of guys with them), your home, etc., and then just move your SkyFi to whatever one you'll be using. You pay for the subscription for the SkyFi unit itself. If I recall, it's $12.95 a month, and each additional unit per family is $6.95. We now have three SkyFi units and cradles in pretty much everything with wheels, our home stereo, and my office stereo. She has a boombox in her office, and I have one in the garage.

Many newer cars have stereos that are already equipped for XM or Sirius, and many aftermarket stereos are as well. More integrated than an add-on like the SkyFi, but not portable or transferable. Of course, you still have to pay the monthly subscription fee.

If you like music, it's well worth it. If you spend a lot of time in your car, it's awesome. I usually don't even take CDs in my car anymore. Besides every type/genre/period of music available, there's multiple talk radio channels, sports radio, theatre, racing, commedy, etc. One of the SkyFi's is permanently mounted in my car, but if I jump in the truck and forget to bring the other unit and have to listen to commercial radio, I go insane in about 5 minutes.

As for the satellite merger, I wouldn't hold your breath on that. If by chance it does go through, both XM and Sirius have told their subscribers that the merged companies will continue to use all the satellites, meaning you will still get your current channel line-ups using your current equipment at your current rates. Their plans for the future are pretty much like cable TV -- offer a "basic" plan with tiered upgrades beyond that.

I have 3 XM's- one in the kitchen where I am most of the time, one in the bedroom on my night table and the third was in the new car we recently bought (would have installed one if it had been already there). I rarely use the music channels though the variety of music is unbelievable and when I want music I am glad I have the XM. I mostly listen to the talk radio and news channels. There is absolutely nothing that you can't get on XM and I love it. We also drive cross-country every summer and love that there are no dead spots for 3000 miles!