Who remembers the huge fiasco created back in the 80’s with the “format wars” between Beta and VHS, AM vs FM, oh and yes, Motorola vs Magnavox vs Kahn-Hazeltine vs Harris??
Who remembers the huge fiasco created back in the 80’s with the “format wars” between Beta and VHS, AM vs FM, oh and yes, Motorola vs Magnavox vs Kahn-Hazeltine vs Harris??
What was it…oh the market was going to decide.
Well for decades now, other countries like Australia and Japan and Canada have enjoyed AM Stereo radio, while here in the USA we are graciously accepting 5khz of narrow bandwidth sounding crud piled on top a layer of HD digital hash garbage.
Many have wondered just how good does that C-QUAM AM Stereo sound anyway. They have never heard it before, or even recall hearing any AM Stereo signal even back during the “let the market decide and crash it” days.
Well very soon, once I get a few more things in order, all of you, the entire world will be able to hear what an AM Stereo station sounds like via your computer and my station’s 128kps 44.1Khz Steremp3 stream.
Here is how it will work.
A Sony ST-JX220A receiver, modified to tune the expanded AM band, picks up the 1670 C-QUAM signal. The line outputs are then fed directly into the encoding computer’s sound card line input. The encoder is set for 128kps, 44.1Khz sampling stereo mp3 stream.
You will hear the AM stereo signal in its full fidelity. No stupid NRSC curve on it, no “loudness war” nonsense processing on it, just pure wide range AM Hi-Fi stereo audio as it is meant to be heard, no alterations to that received signal or its audio out the back.
The only processor in use is at the audio input to the C-QUAM exciter, a Behringer 9024.
Be watching for the big announcement when it comes online!
RFB
Awarded in Advance
Good News RFB!
Your C-QUAM Stereo Demonstration has been named “Low Power in the News Story of the Episode” in advance of both the Demo and the episode.
I am still thinking ahead, maybe we can make that section of the LPH actually in stereo, so the Demo will get carried through.
Stereo LPH Segment
That would be real easy to do. However you will want to record the whole episode in stereo tracks (2 tracks) even if the audio itself is mono for the other parts of the show.
The reason why is you want player codecs to properly see the two tracks the whole time so when the actual stereo audio runs, there is no player hiccup due to seeing only 1 track and suddenly there are now 2 tracks to decode, then back to 1 track.
That might play havoc with on demand players and even automation playback as well as muck up a stream.
But its a good idea!!
Very soon kids. Very very soon!!
RFB
I’d give anything to broadcast in C-QUAM
Every time I can tune in 890 WLS or 1630 KCJJ on my old 1994 Chrysler Concorde stereo (which I put in my 93 Concorde because I wanted AM stereo), It is AMAZING!!!!! The fidelity is so rich! It’s like surround sound in my car.
I would love to broadcast Channel X in AM Stereo. I keep trying to find some sort of stereo generator that could be used with a talking house transmitter.
I’ve also been looking for a cheap talking house online.
Another dream of mine is broadcasting in DRM on 1670KHz. I wonder if the 100mW DRM signal would travel farther than the analog signal. I know a 250 watt IBOC FM station travels farther than a 250 watt FM translator. WKFS-HD2 travels about 5 miles farther than their translator on 106.3 (which I HATE!!!!! I want my frequency back!!!!!)
I have a C-QUAM receiver, but no transmitter
I have a Sony SRF-A100. It
works great, but the front
is badly damaged cosmetically.
What a shame.
Since that kit in the U.S. has
been discontinued, I guess there
is no fairly inexpensive way to
transmit Part 15 C-QUAM.
RFB, your set-up is a great idea!
We will all be checking it out.
By the way, there are some C-QUAM
stereo AM recordings on YouTube.
The best sounding ones are from
stations in Australia that no longer
exist. There used to be a recording
from a C-QUAM stereo station in Japan.
It was unbelievable how good it sounded!
I can’t find that post on YouTube now.
Bruce, DRS2
It’s A Sony!
“I have a Sony SRF-A100. It works great, but the front is badly damaged cosmetically. What a shame.”
Let the cosmetics not get in the way of enjoying that SRF-100! I had one of those when it was first introduced. For the life of me I cannot remember what happened to it. I just know that much later one day, I remembered I had one and never have been able to find it!
“Since that kit in the U.S. has been discontinued, I guess there is no fairly inexpensive way to transmit Part 15 C-QUAM.”
Ooops..did I forget to mention something in my initial posting?
Let me check…yep I neglected to mention I am working on a C-QUAM AM transmitter kit design. 🙂 No this wont be a tug of war of what is more efficient etc etc, but this design, a seriously updated and cleaned up design based on the Alfredo Lite (C-Cuff) AM C-QUAM transmitter.
I don’t expect much appeal for it as there is not many receivers capable of picking up AM stereo except for vintage equipment or hand made receivers or from Japan. But I am working on a design and perhaps a re-kindling of the flamethrower stereo torch can be lit once again.
RFB
I am also interested in doing
I am also interested in doing AM Stereo VIA C-QUAM stereo.
Perhaps we or you could build a C-QUAM stereo receiver to sell though the network ?
RFB get where I am coming from 🙂
Marketing a new way of Radio…..
Now if our stations sounded
Now if our stations sounded like this one , We would have something to offer the market that would really shock the big guys.
http://vimeo.com/22728658
Potential
“I would love to broadcast Channel X in AM Stereo. I keep trying to find some sort of stereo generator that could be used with a talking house transmitter.”
Well a TH unit can be fitted with a C-QUAM generator and 90* phase shift register on the main oscillator counter so you have the 0* and 90* envelopes, then you have to add the L+R and L-R modulators for those envelopes as well as the audio matrix in front of all that. Then you have to add filtering on the injected L-R envelope so that any digital hashing from the counter doesn’t pass through and be demodulated on the L-R audio in the receiver.
But even though this can be done, it’s not advisable if you want that TH or iAM unit to retain it’s FCC certification.
I have not seen any lately but perhaps a C-QUAM unit will show up on ebay. Only place I know of making anything C-QUAM for low power AM is AsPiSyS in Greece who makes the ASMAX-1 AM C-QUAM exciter/transmitter.
I might have a C-Cuff C-QUAM board around here somewhere I can let go. Will advise.
RFB
C-QUAM
Well, RFB, if you designed a
circuit that transmitted C-QUAM,
I would build it. (It would take
me five years, but I still would.)
Lefty, I just listened to the audio
“clip” from KCJJ via the link you
offered.
I called KCJJ on the phone. They
are in Iowa City, IA. Yup, they
are still transmitting in C-QUAM.
On 1630, 10 kW day, 1 kW night, omni.
I might just call all of the stations
in the U.S. that are on the C-QUAM lists,
and see if they are still doing this mode.
I would be an easy project.
Supposedly, there are 3 stations in CT that
do C-QUAM still. I will have to check them.
One station, I can just barely hear, and it’s
still doing it.
There is a rumor that 50,000 watt WLS in
Chicago does C-QUAM at night. I’ll have
to call them and check on that, too.
Bruce, DRS2
Outsider Sticks Head Inside
To the disappointment of RFB I do not transmit stereo because the human voice is a monaural instrument and lower bit rates on streaming radio saves bandwidth.
Yet, having a very dual-natured mentality, I love the perfection of technology that C-QUAM provides, and some days I am tempted to broadcast in C-QUAM mono.
Locally, a 690kHz AM station, 1kW, claims on their website to be “stereo”, but maybe they only mean their stream.
This is the fourth paragraph and I finally have a good question to ask: is there a way to determine if a station is C-QUAM by looking on the signal analyzer?
One thing I’ve noticed is that KMOX, 50kW 1120kHz, now turns-off their HD buzzer at night.
Hi Carl!
That’s very considerate of KMOX
to do that. I have listened to
them for decades.
About 15 or 20 years ago, a local
AMer moved from 1440 to 1120, and
received permission to go on at
night. They are about 20 miles
away. I can null them out and still
hear KMOX.
At one point, my AM DX set-up was so
good (I had an adjustable phased wire
antenna system) – I could hear AM stations
next to our local flamethrower, WTIC, Hartford,
1080 kHz. In other words, on 1070 and 1090.
I could null down WTIC’s “side-hash” to a
very low level. Then things on the adjacent
channels would come in. It was interesting.
If I tuned to around 1088.5 to was easier to
hear 1090, because there is less hash there.
It was the same with 1070. 1071.5 worked a
little bit better. It was a delicate balance.
though.
Bruce, DRS2
75 C-QUAM Stations in the U.S.?
I just found a list and counted the
stations. I don’t know how good the
list is, but if it is really 75 stations
that’s pretty good.
Can anybody with C-QUAM receiving equipment that is near
WLS in Chicago – 50 kW omni day/night –
try to check them? I will try from here
in Connecticut, too. WLS in listed as C-QUAM
as mentioned before. I wonder if they really
are?
Bruce, DRS2
We Can Try
Hi Bruce!
I can receive WLS at night, but I don’t know how to check for C-QUAMishness. Is there a way?
Many station web sites give little technical information. They really should all have technical pages showing powers, pattern maps and transmitter/tower photos.
You know, it would not be a part 15 violation for us to show a picture of a 2,000-foot tower on the KDX website, shown attached to an sstran AMT5000.
I’ll have to produce something for you to announce. I’ve been gathering bits and pieces for the next show. If I’d have one fewer lunches maybe …..
How To Tell
One way is to tap an AM radio’s IF frequency and run that into an o-scope with a 25hz brick wall filter. You should see nothing but a 25hz pilot tone waveform on the scope. If present, they are transmitting C-QUAM.
Of course the easier way is to use a radio capable of receiving C-QUAM.
RFB
A Curious Question
What percentage of modulation level is the 25 Hz pilot?
If a clear audio signal were put on a VU meter, could the pilot be noticed during dead air?
I recall that the sub-carrier for FM stereo is around 10% mod.
Pilot Flying Levels
In FM, the pilot tone is 19Khz, which is audible. The receiver has brick wall filters that knock out a great deal of that pilot tone so it is not heard through the speakers. Yes it is around 10% deviation.
In AM, the pilot is 25 cycles, or 25hz. Again the radio receiver (C-QUAM) will have filtering to block out this 25 hz signal. You wont see it on the audio outputs. This is why you need to tap the IF frequency just before the mixer so you can see the tuned signal directly. Adding the 25 cycle brick wall filter will prevent your measurement from being influenced by any audio content above 30hz.
The level should be around 5 percent. (2.5+, 2.5-)
The 25hz pilot has a very different job than that of an FM’s pilot tone. The FM pilot tone is merely a high frequency audio signal that does just one thing..tells receivers to activate the 38khz sub carrier decoder for the L-R information. The L+R is already there.
In AM, that 25hz pilot tone does not just tell the receiver to activate the C-QUAM decoder, it also tells the C-QUAM decoder’s envelope detectors where to “park” in proper phase relationship to the main envelope and the 90* shifted quadrature envelope..ie tell which one is the 90* shifted envelope lobes for the L-R in relation to the main envelope containing L+R. The 25hz tone synchronizes the decoder chip to the transmitted 25 tone so it’s detectors are in correct phase relationships with that incoming signal.
RFB
WLS IS in stereo
I’ve tuned in WLS in glorious AM stereo on my car radio many of nights while driving home from work. It’s a talk station (which SUCKS! I want MUSIC!!!!!) but it’s in stereo. As my quote in parenthesis shows, I wish I could find a stereo music station. KCJJ has only came in once. 1630 is so crowded around here.
Question for RFB.
What is
Question for RFB.
What is needed to build an AM Stereo Receiver ?
What parts are needed beyond the Standard AM Receiver and a Stereo Receiver?
WQUN, Hamden, CT, 1 kW day, 350 W Night C-Quam 1220 kHz
This little AMer is 27 miles from me.
I checked them today and they are still
doing C-QUAM. I can only hear them
during the day. And the best when the
radio is outside.
I called them and told them I was listening
to their C-QUAM.
They were thrilled! I know I’ve mentioned
these guys before, but I guess I’m just lucky
that they are still there.
A question to channelX1610 – so you heard
WLS’s C-QUAM fairly recently? I’ll have to
check them out when I get home.
Bruce, DRS2
The First Stereo on Radio
Have you guys and I hope someday gals ever heard about the first experiments (as far as I know) for broadcasting stereophonic sound by radio?
It was before FM stereo was introduced, but just around the time stereo albums came along.
If you pledge to put part 15 in your will I will tell the story.
Or, someone may also know some early stereo history.
Carl – Is this about WQXR?
Carl – is this about WQXR?
(Echo Echo Echo.)
Broooooooooooooooooooooooooooooce, DRS2
Nope
Is WQXR in New York? I should know.
But the stereo experiment I know about was in St. Louis Missouri 1960.
I’d Like To Hear About It Carl!
It has to be better than in 1969(?)
when I blew up my SONY reel to reel deck
trying to transmit AM stereo through
2 different AC/DC type “phono oscillators.”
ZZZZZAAAAAAP!!!!! POWWWW!!!!!! (burning smell.)
(I know quite a few of you have already
heard that story.)
Bruce, DRS2
P.S. WQXR was an institution in New York
City as a classical station on 1560 kHz
and 96.3 MHz. They got bought out and
no longer exist, although the call sign
is probably floating around somewhere.
Logging the AM here in Hartford, CT was
easy. It took me decades to hear the
FM on 96.3 MHz, because I was only a
few miles from WTIC FM on 96.5.
Stereophonic Sound Early Days
In the mid 1950s a guy I ended up knowing for many years applied for the license for 93.7mHz, which had been run by the Star Times Newspaper of St. Louis. The story before that is about “bus radio,” but I’ll tell that over some other camp fire.
During the last year of high school I was hired as announcer/board operator at KCFM, we had very diverse programming.
Meanwhile, the longtime power house, KMOX 1120kHz 50kW had a local symphony conductor host Sunday nights (Laurent Torno) and I forget what order these things happened in, but on several occasions the Laclede Little Symphony was broadcast live, with one channel on KMOX-AM and the other channel on KCFM. People were instructed to place there radios about 8-feet apart and stand in the center. This was also done with stereophonic records.
A year or so later KCFM became the second station in the U.S. to have FM stereo (I think the first was WBZ-FM Boston)
During those stereocasts my job was to patch the 15kHz equalized phone line for the right-channel feed.
Also, Mr. Torno’s voice was only heard on the AM station, so to avoid dead air on the FM, I was instructed to play soft instrumental music at a low level so our audio didn’t conflict during the shared venture.
I think it was somewhat popular, but maybe it wasn’t. Anyway, they gave it a try.
I went home and tried the same thing with two Knight Kit transmitters using stereo railroad train sounds.
I never got over the excitement.
Early Birds
The first tests of stereo radio transmission took place in the 1920’s with two AM stations on two different frequencies.
Worked really well, except for the problems of propagation delay between the two signals reaching a reception point precisely and what happened was those within a few miles range got good reception of both signals and very little propagation delay, but those much further away, experienced all sorts of echo and delay between the two signals.
RFB
I last listened to WLS 2 days ago
Their still loud and clear in C-QUAM. It’s a shame to see it wasted on a mono talk format. They need to bring back the music. But, the awesome experience is still there. You can still hear the higher fidelity.
Thank You For The Info ChannelX1610
I will try it when I get home from
work tonight.
Bruce, DRS2
Is It Real?
Some current AM stations still equipped with the C-QUAM systems will run their transmitter in C-QUAM but their audio is actually dual channel mono, ie left and right mixed together then fed to the left and right inputs of the C-QUAM exciter.
The reason? So that C-QUAM radios and HD radios with C-QUAM chipsets will “open the bandwidth floodgates” so that audio, even talk format, sounds crystal clear with fidelity and dynamic range.
When commercials air, see if you can “hear” actual stereo audio from bed music within the commercial. If you hear distinctive left and right separation audio, then their studios and transmitter links are still full stereo, as is their signal.
RFB
More C-QUAM Reception Tests
Yesterday, I had checked that 1220 1 kW
station I can only hear during
the day, and I heard the C-QUAM,
but the station was weak. (27
miles away, as mentioned before.)
I dug up my regenerative AM BCB
amplified loop, and put in on
the Sony SRF-A100. Oh man – I
could REALLY hear the stereo
this time.
There is a 1230 right next door
that splatters, but I was able to
null most of that out with the loop.
Also, I tried for WLS, 890, in Chicago
last night. Although sometimes they
come in great here in Connecticut,
last night I wasn’t lucky. The 890 channel
was a mess, so I will have to try that
again.
I’m going to try for a couple of other
very weak and relatively far away
daytime C-QUAMs, and one “Khan”
station.
“Did she change her hair style?”
“I hadn’t noticed.”
Only RFB will get that quote.
Bruce, DRS2
Bruce, DRS2,
Bruce, DRS2,
I’m a relative newcomer to this but are there still Khan stations. I thought that they’d adopted c-quam as the only acceptable system?
Sincerely,
duophonic
WLS is hit or miss sometimes…
…even in Ohio. I’d be kind of surprised if you got a signal all the way in Connecticut. But you might have a better setup than my Chrysler car radio. Seems like Chryslers are notorious for bad radio reception. Even my FM dial has static pops on local stations as you drive down the road. My old Nissan didn’t. Gosh, I miss that car. It was great on gas. Filled up my concorde yesterday and it cost $70!!!!!!! Lousy $3.73 a gallon gas. It’s ridiculous! But, I’m starting to go on a rant. I’m gonna stop my gas price rant and get back to the C-QUAM post.
I took a listen to that KCJJ clip. I almost thought it was fake. It sounded like someone recorded the internet stream and passed it off as AM stereo. It was that good!
Hi Channel X 1610
Yup, you are right about WLS.
But even in Connecticut, where
I live –
on some nights, all the Chicago
stations that are still running
on clear channels come in great
here.
A lot of the callsigns have changed,
but when conditions are right, I can
hear 670, 720, 780, 890 (WLS),
and 1000 kHz without any trouble.
I love checking the propagation on the
AM BCB. The batteries ran down in the
Sony SRF-A100 C-QUAM receiver – I have to put them into
the charger and check again tomorrow night.
Best Wishes,
Bruce, DRS2
Little DX Results
Out here it’s quite difficult to tune in the “flamethrowers” (COUGH) here in Wy. Best time for cross nation DX reception is in the winter when almost the entire state is covered in several feet of snow.
Even our clear channel 50KW KTWO AM 1030 is difficult for DX’ers to hear until the winter season. But KTWO changes pattern at night but keeps the 50KW power level. I do know this, when they switch to night pattern, the ghost image noise that appears on 630, 1230 and 1630 goes away, and during their daytime pattern (omni), those frequencies are plastered with ghost image carriers sounding like they are being over driven in modulation by about 400 percent.
This winter I may try taking my “Great Loop” outdoors and mount it on a short pole and a rotor, try to pick up on these stations to my East everyone is talking about.
RFB
Shock And Awe
“I took a listen to that KCJJ clip. I almost thought it was fake. It sounded like someone recorded the internet stream and passed it off as AM stereo. It was that good!”
Every visitor to my station has been given a first hand hearing experience between the FM stereo station and the AM stereo station. All of them swear they were still hearing the FM when in fact the studio monitors were producing the Sony ST-JX220A AM stereo receiver that is used to monitor AM Stereo 1670.
They could not tell the difference at all.
I had one visitor actually tell me to put it back on the AM receiver when I was switching back and forth between it and the FM receiver. They stated it sounded more natural, fuller and warm.
And it really does.
RFB
Locals KGVL & KKLF are Stereo KMKI-AM Used to be
the only am stereo station worth listening to on am is KGVL AM 1400 out of nearby greenville which broadcast oldies which sounds neat in stereo (i haven’t confirmed with KGVL Radio if they are broadcasting in stereo, but on the times i caught the station on my grandmothers receiver which said it was in stereo but it could be a false indication but if it is true and if they are in stereo i GREATLY Applaud the station for doing so), and KKLF AM 1700 is talk from Susquehanna, nothing really fancy but the 50 KW station i enjoy listening to at night is KWKH-AM 1130 Shreveport, LA.
KMKI AM 620 Radio Disney (me and my old friends called it K-Mickey)used to broadcast AM Stereo and when i was 5 or 6 years old i had a sony portable walkman that got am stereo and bragged about it to my friends on how good they sounded on my walkman because they were am stereo, i dont have any recordings but take my word on this, they were THE BEST SOUNDING HI-FI AM Stereo Station for a KIDS Music Station! Hahahahahahahahahaha!
Further Update
The 2nd Sony ST-JX220A receiver is slated for delivery today, Monday August 13, 2012. This second receiver will be used to feed the 128kps 44.1Khz stereo mp3 stream encoder.
The first Sony ST-JX220A receiver will still be used as the main AM studio monitor receiver.
I wanted to have two receivers so that when I switch over to the FM band to check up on that part of K-Rocks, that I don’t disrupt someone’s enjoyment of wonderful warm AMazing AM stereo sound!
Very soon kids!! Very very soon I will make that big announcement that now the whole world can hear an AM Stereo C-QUAM station in it’s full warm and natural sounding stereo!
I may just go ahead and have the AM stereo receiver feed all 3 of my station’s streams. Save a lot of work for me! 😀
RFB
Stereo in Mind
I seem to recall that channel separation between left and right on FM is somewhere around 45%, which means that you can never have one channel go completely silent with audio on the other channel.
How good is channel separation on the C-QUAM system?
If channel separation were 100%, it would be possible to broadcast two different mono programs at the same time on one transmitter.
FM Stereo Separation
I seem to recall that channel separation between left and right on FM is somewhere around 45%, which means that you can never have one channel go completely silent with audio on the other channel.
Hi Carl, et al… Probably this recollection is related to the fact that both the L+R main, and L-R subchannel signals modulate the main carrier of an analog FM stereo station to about 45% each, which allows for about 10% modulation of the main carrier by the 19 kHz pilot.
However those modulation percentages don’t define the separation of the L&R channels at the receiver. That channel separation is a function of the FM stereo encoder/transmitter and receiver/decoder used, and the quality of the transmission path between them.
Optimally, analog FM stereo L&R separation can be 60 dB or better.
But even 30 dB L&R separation in a normal stereo program is audibly near perfect, because there almost never is a time in natural program sources and their (accurate) recordings when L = 100% and R = 0%, or vice versa.
Better Said
The description by rich of FM stereo improves my understanding about it, and I can understand why the stereophonic imagery is very much preserved by the specs mentioned.
After all, with our human binaural hearing we always hear something in both ears, even when a louder sound is only on one side, unless of course we stick oatmeal in one ear.
How does C-QUAM AM stereo compare?
And this is just a silly thought that popped up — if you have 3-D sound on a staircase it’s called staireo.
To The Left..On The Right
Yep, around 30 to 35 is optimum separation (normal 2 channel).
C-QUAM can hit up to 40 if you carry out the IF notch to about 11 or 12Khz.
At 10khz its around 30.
And ooh so sweet. Like listening to a fresh brand new vinyl on a brand new Stanton 500 cartridge.
Ain’t noting like that smooth warm analog sound.
RFB
Testing
Between now and when the setup is finalized, I will be conducting tests streaming AM C-QUAM audio from a Sony SRF-42 receiver. There is a test currently going on now (3:00pm MT).
When completed, all 3 of my station’s streams will be fed audio directly from the Sony ST-JX220A receiver.
If your tuned in to the streams, your listening to an over the air signal at this very moment.
🙂
RFB
Fidelity is Sky High
I listened from about 3:10 PM MT and the presence, completely undistorted, very wide-frequency response, was a magnificent 3-D sound.
RFB knows how to milk the radio cow.
AMazin’ AM Stereo
That used to be a slogan on one of Sony’s old AM Stereo receiver banners.
And if you think it sounds great off the Sony SRF-42 receiver, which by the way is a walkman receiver sporting AMAX, just wait till you hear the C-QUAM from the ST-JX220A receiver!
It’s well…AMazin’!
RFB
Concluded
Today’s short tests of the AM C-QUAM streaming has concluded.
There will be a few more over the next few days.
RFB
Tests Today August 22
More tests will be conducted with the C-QUAM streaming on K-Rocks. All 3 streams will have the AM Stereo C-QUAM receiver line level audio going through them.
The tests will be random and throughout the day. Since most of today’s programs are music oriented, should be an enjoying listening experience!
The receiver being used in the tests is the Sony SRF-42 AMAX walkman.
The best way to tune in is to use the links at the top of the site right below the main banner K-ROCKS. They are in red font. Each is a link with abbreviations for Winamp (MP3), Windows Media Player (WMP), Real Player (RM), and Flash. There are 3 stream bitrates, which is noted in each link by the bitrate number, 128, 48, 24AAC+. Bitrates are Kilobits per second (KPS).
Just choose your preferred player’s link. If not sure, just click one of the MP3 links, 128 for the best sound.
Comments welcome!
RFB
3-2-1 LAUNCH!
Today, as of 5:51 AM Mountain Time, the Sony ST-JX220A receiver is tuned to K-Rocks AM Stereo 1670 and feeding all 3 internet stream servers full time.
Tests complete. Enjoy C-QUAM. 🙂
RFB
Full 24 Hours C-QUAM
For just over 24 hours now, K-Rocks AM Stereo 1670 has been the station’s 3 stream audio source from a Sony ST-JX220A FM Stereo/AM Stereo component tuner.
I have received “reception” reports from outside of the forum’s membership, but no one as of yet from the forum other than those during the testing phases! 😕
For the best and most closest accurate sound reproduction, tune to my station’s 128kps 44.1Khz stereo mp3 feed. But the other two streams, the 48kps, 24khz stereo mp3 feed and the 24kps 44.1khz AAC+ feed sound quite good as well.
Here are the links:
External/installed players (Winamp/VLC/ETC)
Standard 128kps mp3 stream. Practically any player on a computer will have no problem playing this stream.
Standard 48kps mp3 stream. Again any player should have no trouble connecting.
24kps AAC+ stream. Not all players will play an AAC stream. Certain players like Winamp, Windows Media Player, VLC player can play an AAC stream. Other players may require a plug in or update. Check your player’s documentation for more information on options.
Embedded player links (web page player)
128kps Windows Media Embedded Player.
48kps Windows Media Embedded Player.
24kps AAC+ Windows Media Player.
Flash Player (web page player)
128kps 44.1khz stereo mp3 stream.
48kps 24khz stereo mp3 stream.
Unfortunately Flash player cannot properly decode an AAC or AAC + stream by default.
Currently the tuner is feeding the encoding computer’s line level input and the encoders are set to encode from that line input. There is no equalization applied, no basic tone control applied. Just plain line level out of the tuner to the line input of the stream encoding computer. No enhancements to that audio signal with any encoding processors or plug in’s. This allows for a realistic listening experience through the use of your own sound enhancement preferences just as if this tuner was connected to your audio system.
What you hear when you tune in to one of those links is unaltered demodulated AM C-QUAM stereo audio directly from the Sony ST-JX220A tuner.
So you are tuning in to a tuner tuned to an over the air signal, which at this moment, and for the last 24 or so hours, is the ONLY Part 15 AM radio signal with the furthest reach well beyond 1/2 mile or the 94 feet 221 distance with a little help from the web!
I would most appreciate “reception” reports from everyone and anyone tuning in.
Thanks and enjoy C-QUAM AM Stereo sound!
RFB
Temporary Compromise
Motorola’s C-QuAM along with NAB’s AMaX are a good compromise on the road to a fully digital system like DRM for unlicensed low power broadcasts. Manufacturers of Part 15 equipment should definitely incorporate such capability into their kits.
Although I still adhere to my
Although I still adhere to my previous observation for most situations, I think C-QuAM plus digital radiograms could be a close substitute. As we all know, C-QuAM can sound terrific on both musical and verbal sources. My station’s content demands textual and graphical capability which can largely be handled via a radiogram. Even at high bit-rates, I’m not convinced that any digital format can beat C-QuAM with musical content, however. I do wish that some innovator would crowd-fund a compact, AMaX C-QuAM receiver with the ability to decode radiograms and display the concomitant text and graphics. Could such a receiver help populaize AM stereo?
Currently, instead of a Title 47, Part 15 Digital Radio Mondiale transmitter, I just might settle for a Part 15 C-QuAM transmitter and radiograms…