AM Stereo Frequently Asked Questions (and their answers too)
Q: What is AM Stereo?
A: AM Stereo is a method of
transmitting stereo over the AM band using Motorola C-quam technology. In
THIS capacity anyway. A little history - Originally there were several
systems in use to transmit AM Stereo and it eventually came down to 4 systems -
Motorola, Kahn-Hazeltine, Harris, and Magnavox. At this point in time
(which would be about 1982) the Federal Communications Commission decided to let
the systems market themselves and let the public marketplace decide which was
the better system. With there being different systems out there and
different stations installing different systems, many say this is why the whole
idea never "took off" like it should have or could have. Sony manufactured
many receivers that decoded all 4 systems and there were a few other
manufacturers that did as well. But the market never got "saturated" with
radios. So not many people had them and that's why still today not many
will remember "AM Stereo". Some say that if the FCC would have mandated a
particular system, then the market could have been flooded with receivers and
more manufacturers could have manufactured them. In November of 1993, the FCC
actually DID mandate Motorola's C-Quam system as the standard for AM
Stereophonic broadcasting in the U.S. and it still is today.
Q: What makes it better?
A: STEREO, of course.
We were born with 2 ears, not one! Seriously, we've had FM stereo
for such a long time and it's almost a "given" that FM is stereo. AM is
stereo too when a station is broadcasting with AM Stereo technology.
Q: Can I buy a radio that
receives AM Stereo?
A: You sure can! They
aren't as widely available as regular radios are and you won't find them at Wal-mart.
However, AM Stereo is still in use in other places in the world like Japan and
Australia and Canada, as well as here in the U.S. Sony makes several
models that they market in Japan, however you can purchase them through
Audiocubes.com . Ebay is another good source of AM Stereo radios, however
beware...there are still many collectors of AM Stereo gear and many AM Stereo
radios sell on Ebay for much more than what their original cost was. Jeff
Deck has also built a high-quality tuner that is available for purchase.
Visit his web site for information on this tuner and more about AM Stereo at
http://meduci.com . Jeff also maintains
the list of stations broadcasting in stereo. Click
HERE for the station listings.
Q: What about for my car?
A: Some of the best sources
for AM Stereo radios for the car are actually junk yards or Ebay.
Sometimes it's tricky telling whether a radio receives AM Stereo or not without
being able to plug it in an tune to an AM Stereo station. However, you can
go to the RADIOS page and find any of a number that are
compatible. Even today there are still some radios being manufactured and
put into cars - Ford and Chrysler are some that AM Stereo still show up in.
Again, see the RADIOS page for details.
Q: Okay great! Now I know
how to get a radio. So what's there to listen to?
A: Glad you asked! See
the STATIONS page for a complete
listing of the stations still using AM Stereo today. Or make your own
station! Please EMAIL US for details
on how you can get your own C-Quam AM Stereo transmitter! We have a few
people that make small AM Stereo transmitters that are "Part 15 Compliant" -
miniature transmitters that are perfectly legal and will broadcast beautiful AM
Stereo all around your house or yard....all you need is a computer or IPOD or CD
Player ... anything with a headphone jack that you can use to feed the audio
into it.
Q: How good does AM Stereo really
sound? I've always thought AM sounded like crap.
A: The reason AM sounds so
bad is not the stations, but the radios. ALL AM stations are authorized to
broadcast audio up to 10 kilohertz. That basically means that most
stations are actually broadcasting audio that is crisp and clear, yet you need
the right radio to RECEIVE it that way. This is why we say a good radio
that has good BANDWIDTH (nice crisp highs on the AM side) can even make a mono
AM station sound good. Today there are some AM stations out there that are
limiting their bandwidth to about 5khz or 6khz. Many Clear Channel AM
stations have instituted a policy of limiting their audio to a much lower
bandwidth since most of the radios these days are "deaf" above 5khz.
(well...they sound like crap). It is also noteworthy that stations that
are using a new digital technology called IBOC are also limited to 5khz
bandwidth on their analog signal. However there are still thousands of AM
stations broadcasting the full 10khz worth of audio and on a good radio will
sound excellent. Even if they aren't AM Stereo. Radio manufacturers
have the power. They are the ones that can manufacture a tuner that has
great bandwidth on the AM side if they want to. However, most don't.
Why? We don't know. Many of believe that if manufacturers would have
manufactured better-sounding AM tuners back in the days when FM started catching
on because of its "clarity" then AM may still be a viable medium today. AM
can and DOES sound good. You just have to have to radio to bring it to you
that way. If you ever get a chance to tour a radio facility that has an AM
station, go into the studio for the AM station and chances are you'll hear their
on-air audio in the studio in a much different perspective as most radio
stations monitor their audio with a modulation monitor - which is a wideband
receiver that can hear the full range of the AM signal. You may even think
you're listening to FM! Take that clarity and crispness and add STEREO to
it, and there you have it - great sound! AM Stereo!
Q: I've heard about all this
digital technology and stuff. What's that all about? Is it AM Stereo
too?
A: The short answer is - yes
and no. Again, when we talk about AM Stereo for the most part we're
talking about analog C-quam. However, with IBOC digital technology, the
digital signal can be broadcast in stereo as well. It's still a very new
technology at this point. Basically the analog signal is still where it
always was, but there is a digital stream broadcast along side the analog
signal. This digital stream generates horrendous noise. If an AM
station is using IBOC, you'll know it because on an analog AM radio you will
hear tons of harsh "hash" on either side of the station. An IBOC
receiver takes this digital noise and decodes it into audio. Some that
have heard these digital signals will say they are only mediocre and resemble an
internet audio stream. IBOC has been approved for nighttime use now and
due to the properties of AM at night and the ionosphere, the IBOC noise travels
great distances. The interference is greater than ever due to the
noise....some stations are even shutting if off again at night.
We AM Stereo lovers are hoping that the government will approve IBOC for daytime
use and C-quam AM Stereo for nighttime use. It makes sense, since C-quam
does not cause any harm or additional interference at night. Stay tuned to
this web site and we'll keep you posted on that situation. In the meantime
there are only a handful of stations using IBOC digital and HD
(High-Definition....another word for IBOC) radios are still hard to find and
very expensive. No one knows where the future of AM lies right now so we'd
rather make the best of it and enjoy those stations that are still using analog
C-quam AM Stereo and there are more out there than you may think.
Other questions? Please EMAIL us or join us at our AM Stereo message board. For more information on our group, please see the message board page.