I actually met a live human being who owns an HD radio tonight.

[BRNout]

And, if you crank up the power on the HD signal, you obliterate even more of the band with static.  It's such an inefficient system.  What I mean by that comment is you can have the digital sidebands interfering with adjacent frequencies for a good percentage of the analog signal's range. 

For example, WBBM's sidebands obliterate 770 and 790 (day and night) as far away as Milwaukee and Davenport, IA.  Yet, that same digital signal can only be decoded for 30 miles with an excellent HD Radio/antenna setup.  So, a radius of annoying buzz and hiss for a good 160-180 miles, yet (at best) 30 miles of usable range.  Very, very wasteful thing to do with the MW band. 

[Savage]

rbruce, I concur with your assessment that C-QUAM AM stereo actually sounded superior to FM stereo.

I did afternoon drive on WWKB Buffalo, 50kw DA-1 ON 1520 kHz in its final days as a music station, my last (paid!) gig before I put WYSL on the air.  KB was a C-QUAM pioneer and had an unusually fine audio system.  Most of the credit goes to then-CE Tom Atkins who was not only one of the best radio engineers I've ever met but was also a remarkably talented and funny on-air performer.

I actually used to defer taking my headphones off after doing a set...the audio was that good.  It was astonishing listening to the output from the audio section of the TFT mod monitor.  The C-QUAM had a unique presence and richness lacking in most FM products.  When I would make my claim to industry and non-industry people, I was greeted with skepticism, but when the more discerning ones actually tuned in on a C-QUAM capable receiver of any decent quality they would agree.  There used to be an AM stereo page with stereo airchecks available on the web but I can't seem to locate it any more.

[RadeoEngineer]

As long as the engineer balances the audio level and the time delay (so do it well and some do it awful) I find it virtually impossible on HD-1 to hear the switch between analog and digital. 

So it sounds the same in either mode?  There's a screaming endorsement if I ever heard one.  I bet that station is glad they spent all that dough for undiscernable difference in audio quality.

[stormy01]

There used to be an AM stereo page with stereo airchecks available on the web but I can't seem to locate it any more.

Well, I searched on the web using the words "AM Stereo Airchecks", and I got this one, for example: http://www.geocities.com/amstereo2000/  Enjoy!

[audioguy]

A few years ago when WGN was still running CQUAM and also had some music programming overnight and on Sunday mornings, I made some cassette recordings. I was shocked by how great they sounded! I have a Radio Shack AM stereo tuner, which I have modified by replacing the IF filters with wider ones. I also tweaked the high pass filter in the audio section to improve the bass response. Although cassette tapes (even recorded on a component deck) are not the epitome of high fidelity, those recordings were amazing!

Unfortunately for a number of years during the heydey of AM stereo, I did not have a receiver. I had lent my Radio Shack tuner to a colleague at work, who somehow kept forgetting to return it. After the last of the local AM stereo stations went off the air (probably WGN), he remembered to bring it back.

Now here's a practical question for the two or three HD radio proponents on this board who keep on needling those of us who care about audio quality and spectrum pollution: if you lent out your HD AM radio to one of your friends, would you have a hard time getting them to return it??
 

[KB1OKL]

I had an AM stereo radio in my 88 Plymouth and it did sound great, much better than AM IBOC will ever sound and even better than that was the fact that I could drive all the way to Vermont at night from MA and listen to the same station in stereo without switching the station. I have a great sounding C-Quam radio now, the Meduci, too bad there are no C-Quam stations around here, it sound good even in mono.

[Nick]

I met someone else who has an HD radio in his car...in the parking lot of a radio station.