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Something that actually WORKS on AM

Doesn't sound that great to me. That, and the high frequency whistle sounds like the days when AMAX stereo was trying to make inroads. AMAX sounded pretty bad. Having that very song on my IPhone, the example is clearly lacking stereo separation.

And Bruce, how do you know what the building penetration of an MW station in Japan would be? What is the construction type of the building? How far is it from the transmitter site from the measurement location? Is the station ND or DA? Where is the building in relationship to the measurement point? Where is the measurement being made? What is the equipment being used to measure? (hint: not a spectrum analyzer) My point: Just because the audio sounds good to you, is no indication of field strength.
 
I don't know if conditions improved as the song went on or it's the brain's way of masking sounds but after the song really got going, the whistle went away. Considering it's a 500 mile receive path that's impressive sound. I thought since Japan used 9 kHz spacing that their cutoff would be under 10 kHz. I consider myself a fan of AM stereo even with all its quirks and the AMAX whine, but it would never sound this good on a US station because they'd only have a 10 kHz frequency response. Now if we could get C-QUAM and go back to 15 kHz… That would be something to behold on the few receivers that could handle it.

Still, a good quality FM HD feed is even better than this. Here's the format flip aircheck I recorded of a local station a few years ago, transitioning from classic hits to CHR. There's not a ton of music but you can hear during the bit of silence between formats that's dead quiet. And the fidelity overall is superb since it's just a single HD channel, no subs. Granted, it's not much better than this more lengthy aircheck of my local town's community AM station, but it was made under pretty ideal conditions: I'm less than a mile from the transmitter site, they were on full 2.5 kW day power and I was using a carefully aligned Sony AMAX Walkman. The station is mono but you're not at a loss for fidelity here.
 
Speaking of "dead quiet" silence between things, I personally prefer to have a tiny bit of background hiss. Otherwise, I start getting worried and wonder if something malfunctioned, got turned off, batteries died, etc. :) And I noticed what tomservo heard too in this clip, about the sound getting cleaner later in the recording.
 
"Amazing" is a term you use for a song played in quasi stereo vs. mono? Uh, okay.. That's a low bar to qualify as amazing.
 
I wouldn't call that quasi stereo. The separation between left and right is accurate. I remember a teacher in high school and I were listening to that same song on an AM stereo radio one day and he said he had never in 12 years heard that song sound so good, and said "you can actually hear the silence behind the music." It's really noticable when the guitar solo changes to an accoustic right before he sings "When I was tired and feeling cold...."
 
Quasi stereo would be low frequencies on the left and higher on the right which creates a stereo effect but has no real separation. Some records in the late 50's and early 60's were recorded that way (according to my dad) and he said that was an effect to fool the ears into thinking you're hearing stereo. I remember a Cable FM station in Calgary doing that in the 90's.
 
Kelly A said:
Doesn't sound that great to me. That, and the high frequency whistle sounds like the days when AMAX stereo was trying to make inroads. AMAX sounded pretty bad. Having that very song on my IPhone, the example is clearly lacking stereo separation.

And Bruce, how do you know what the building penetration of an MW station in Japan would be? What is the construction type of the building? How far is it from the transmitter site from the measurement location? Is the station ND or DA? Where is the building in relationship to the measurement point? Where is the measurement being made? What is the equipment being used to measure? (hint: not a spectrum analyzer) My point: Just because the audio sounds good to you, is no indication of field strength.
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Most CQUAM stations in Japan are mono now...MW is MW.....penetrating buildings is one killer of MW AM....I have all the audio from WLS' BIG89 Rewinds (both 2007 and 2008) in CQUAM stereo......cant tell the difference with FM playing the same songs
 
mimo said:
Quasi stereo would be low frequencies on the left and higher on the right which creates a stereo effect but has no real separation. Some records in the late 50's and early 60's were recorded that way (according to my dad) and he said that was an effect to fool the ears into thinking you're hearing stereo. I remember a Cable FM station in Calgary doing that in the 90's.
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Oh gosh I remember that. Several broadcast TV stations used to run that fake stereo processing back in the days of MTS stereo on analog stations. I guess it was OK if you watched on a little TV but on headphones or through a hifi it sounded weird.
 
tomservo said:
Oh gosh I remember that. Several broadcast TV stations used to run that fake stereo processing back in the days of MTS stereo on analog stations. I guess it was OK if you watched on a little TV but on headphones or through a hifi it sounded weird.
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It is interesting to me how some posters want to re-direct the conversation into the old quasi-stereo days, claim these clips are quasi-stereo, etc. Fact is - these clips are true stereo versions of the songs, and the quality is really good. It confirms what I experienced in the early 80's - WLS C-Quam in Houston at night at close to 1000 miles was very good.

One reason why I post this is to make a stark contrast between what passes for AM stereo using HD, and the vastly superior C-Quam system. Given that a lot of HD radios have the capability to decode C-Quam, it would be pretty much a no-brainer for AM stations to switch back. C-Quam is more robust, and sounds better. No amount of rationalization will change that fact. Hopefully Mr. Kahn does not make an appearance here, because there is a serious problem with HD AM - and ONLY C-Quam can solve it. If I were somebody at iBiquity, I'd snatch up all the patents and rights fast - and fall back to C-Quam before HD AM is any more dead than it already is! This is the only way to save face in the light of a technical failure. I also point out that any skywave signal robust enough to give that quality at 500 miles is going to peel paint in its home city. HD AM won't penetrate buildings, but C-Quam will go as far as the analog signal will. Two systems - one works very well (C-Quam), the other is terrible (HD-AM). I know which I would run - and I would go right on the air calling my station "HD AM version 2". These ethnic music stations would sound absolutely great! I will have to give WLS a try at night to see if even their degraded signal decodes C-Quam on my HD radios. I never decoded a single HD-AM at night, even when there were some close by. And that is using every DX trick 45 years of DX'ing has taught me. If I can't do it - it is a safe bet your average consumer can't do it.
 
The Japanese stations that Bruce and I posted videos from are 100,000 watt stations. That would have significantly better building penetration that what passes for high power in the U.S. and Canada. One nice thing about CQUAM is the stereo will decode without that much signal. Sony's SRF 42 had what was called "forced stereo" meaning that if there there would be stereo on even the weakest of signals, or if the pilot tone failed, but everything else was still in place. I used to enjoy XEMU 580 in stereo, and that was a very noisy frequency when I lived in southeast Iowa. Sometimes in mono, you couldn't distinguish anything, but the cquam would kick in and all of a sudden there was a very listenable signal playing some great ranchera music.
 
mimo said:
Quasi stereo would be low frequencies on the left and higher on the right which creates a stereo effect but has no real separation. Some records in the late 50's and early 60's were recorded that way (according to my dad) and he said that was an effect to fool the ears into thinking you're hearing stereo. I remember a Cable FM station in Calgary doing that in the 90's.
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Another way they did that was to put one channel out of phase with the other one, sounded like krap. A good mono hifi record sounds almost as good as stereo which is why mono reissues are done in mono today, no fake stereo anymore, it was a lousy sounding gimmick in stereo's early days to fool the public. High Fidelity is much more important to good sound than stereo is, although good stereo is nice. A lot of the junk sold today is lo fi stereo, I'll take a good hifi any day over that. I've got some good hifi records from the 50's that sound excellent, course the late 50's stereo records also sound excellent, you can hear the room in some of the better ones.
 
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KB1OKL said:
Another way they did that was to put one channel out of phase with the other one, sounded like krap. A good mono hifi record sounds almost as good as stereo which is why mono reissues are done in mono today, no fake stereo anymore, it was a lousy sounding gimmick in stereo's early days to fool the public. High Fidelity is much more important to good sound than stereo is, although good stereo is nice. A lot of the junk sold today is lo fi stereo, I'll take a good hifi any day over that. I've got some good hifi records from the 50's that sound excellent, course the late 50's stereo records also sound excellent, you can hear the room in some of the better ones.
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I have to disagree - stereo recordings are much better than mono. But I will agree the fake methods were irritating then, they fooled almost nobody, and would be even more annoying now. A lot of the problem came from cheap record players with mono stylus - they would damage stereo records so a lot of records were released in different mono and stereo versions. Guess what shows up on eBay?! Let the buyer beware - really aware!

Mono purists remind me of people thinking black and white pictures are better because they are more artistic. Well - maybe if you are into that sort of thing. For me, I will take color photo realism. As far as mono - there are two songs that I can think are of interest to mono purists, Rolling Stones "Satisfaction" and Beach Boys "Good Vibrations". To me, the stereo versions are MUCH better, but they probably irritate mono purists.

There is also a movement to convert the old vocals one channel / instruments the other to more conventional stereo mixes. A lot of Beatles songs were that way. I say - leave them alone! What the recording studio did, leave it in. Even the speed flutter in "Here Comes the Sun". This is art, don't mess with it. The thinking on the vocal / instrument stereo being converted to modern stereo is so that it will decode properly in surround decoders. But what do you do with songs that fade one channel to the other - "A Day in the Life" or Jimi Hendrix "All Along the Watchtower". They are going to cause havoc with surround decode. So be it - they were made before quadraphonic and its descendant surround, they should be left alone.
 
rbrucecarter5 said:
I have to disagree - stereo recordings are much better than mono. But I will agree the fake methods were irritating then, they fooled almost nobody, and would be even more annoying now. A lot of the problem came from cheap record players with mono stylus - they would damage stereo records so a lot of records were released in different mono and stereo versions. Guess what shows up on eBay?! Let the buyer beware - really aware!

Mono purists remind me of people thinking black and white pictures are better because they are more artistic. Well - maybe if you are into that sort of thing. For me, I will take color photo realism. As far as mono - there are two songs that I can think are of interest to mono purists, Rolling Stones "Satisfaction" and Beach Boys "Good Vibrations". To me, the stereo versions are MUCH better, but they probably irritate mono purists.

There is also a movement to convert the old vocals one channel / instruments the other to more conventional stereo mixes. A lot of Beatles songs were that way. I say - leave them alone! What the recording studio did, leave it in. Even the speed flutter in "Here Comes the Sun". This is art, don't mess with it. The thinking on the vocal / instrument stereo being converted to modern stereo is so that it will decode properly in surround decoders. But what do you do with songs that fade one channel to the other - "A Day in the Life" or Jimi Hendrix "All Along the Watchtower". They are going to cause havoc with surround decode. So be it - they were made before quadraphonic and its descendant surround, they should be left alone.
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I'm pretty sure the Beatle recording with all instruments in one channel and vocals in the other were recorded in mono and were not true stereo recordings,they just put two tracks (or maybe three) together with one track on the left and the other on the right, someone else here should know. I have some old Everly Brothers high fidelity recordings that sound unbelievable. I'm not a mono purist by the way. There is mono then there is high fidelity mono. High fidelity was the big thing in the 50's before stereo came along, there were some really good sounding recordings made in hi fi back then. True early stereo recordings such as certain jazz recordings made by Rudy Van Gelder in NJ sound unbelievable. Monk comes to mind.
 
KB1OKL said:
I'm pretty sure the Beatle recording with all instruments in one channel and vocals in the other were recorded in mono and were not true stereo recordings,they just put two tracks (or maybe three) together with one track on the left and the other on the right, someone else here should know. I have some old Everly Brothers high fidelity recordings that sound unbelievable. I'm not a mono purist by the way. There is mono then there is high fidelity mono. High fidelity was the big thing in the 50's before stereo came along, there were some really good sounding recordings made in hi fi back then. True early stereo recordings such as certain jazz recordings made by Rudy Van Gelder in NJ sound unbelievable. Monk comes to mind.
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During the studio recording process there's no such thing as recording in stereo or mono. They're multitrack recordings that are mixed down to one format or another. Or as the Beatles did up until The Beatles (a/k/a 'The White Album'), they held completely separate mastering sessions for stereo and mono mixes. In fact, up until that self-titled release, the band put all their effort into the mono mixes because that was their preference, as well as the dominant album medium in the UK up until the late 60s. The White Album was the first to be released as stereo-only in the US and it was The Beatles' first real effort with stereo in mind. That explains why some of the earlier stereo singles were just the 'instruments right, vocals left' style recording, but there was also a technical reason that you're correct about. The standard recording studio in the early days would have had a 4-track setup. Perfect if all you have are vocals (1), bass (2), guitar (3) and drums (4). Each channel could be placed in the stereo spectrum, but if you wanted the drums spread out across the left and right channels things got complex quickly. If I remember correctly, The Beatles were one of the first to experiment with 8-track recording equipment, and then Zappa took it to 16 or 20 channels with computer controlled faders. Something like that. And of course nowadays, it's rare to have anything less than 16 tracks in all but the most low budget of recording studios. Of course these days multichannel mastering is a consideration for many artists, with Left, Center, Right, Left Side, Right Side, Left Rear, Right Rear and Effects channels to work with. (And if we get really out there, there's Dolby ATMOS where you have a 360° sphere of sound created through 128 discreet audio tracks feeding 64 separate speakers in a movie auditorium, but those installations are very rare.)

Like you, I'm not a mono purist; I enjoy the stereo versions of the various Beatles albums that were recently remastered for a CD re-release. But several tracks are very different than the mono versions off the records my parents bought in the 60s, so in a way I wish I had several hundred bucks to burn on the mono box set. And if I ran an oldies radio station, I'd definitely play the mono versions over the stereo ones because that's what people who grew up in this country on their music would have heard until at least 1969. I also recently came across a re-release of Miles Davis' Kind of Blue that's available on HD Tracks in both mono and stereo mixes.

Where I do pitch a fit about purity is when an AM station (or a podcast) is delivering mono audio but the music they play is only the left channel. This happens all too often when stations plug in a satellite music format like oldies or classic country. There's nothing worse in my mind than hearing 'Double Shot Of My Baby's Love' by the Swingin' Medallions and only hearing the left channel, which is vocals and bass only! Apparently you can't just use a Y-patch cable from Radio Shack to sum the channels into one input on the transmitter. ;)
 
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tomservo said:
I don't know if conditions improved as the song went on or it's the brain's way of masking sounds but after the song really got going, the whistle went away. Considering it's a 500 mile receive path that's impressive sound. I thought since Japan used 9 kHz spacing that their cutoff would be under 10 kHz. I consider myself a fan of AM stereo even with all its quirks and the AMAX whine, but it would never sound this good on a US station because they'd only have a 10 kHz frequency response. Now if we could get C-QUAM and go back to 15 kHz… That would be something to behold on the few receivers that could handle it.

Still, a good quality FM HD feed is even better than this. Here's the format flip aircheck I recorded of a local station a few years ago, transitioning from classic hits to CHR. There's not a ton of music but you can hear during the bit of silence between formats that's dead quiet. And the fidelity overall is superb since it's just a single HD channel, no subs. Granted, it's not much better than this more lengthy aircheck of my local town's community AM station, but it was made under pretty ideal conditions: I'm less than a mile from the transmitter site, they were on full 2.5 kW day power and I was using a carefully aligned Sony AMAX Walkman. The station is mono but you're not at a loss for fidelity here.
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Embarrassed to say this is the very FIRST sample of AM Stereo I've ever heard.

Absolutely remarkable IMHO.
 
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stewie said:
Embarrassed to say this is the very FIRST sample of AM Stereo I've ever heard.

Absolutely remarkable IMHO.
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It's a shame everyone gave up on it so quickly in this country. The refrain I keep hearing is it's too expensive to run, or parts are hard to find. Yet it seems like until recently a few manufacturers offered "HD/AM stereo ready" transmitters that could take a C-QUAM encoder card, just there were no cards available. And now, the biggest bugaboo against AM stereo, platform motion, is supposedly cured.

Seems like there was a mass shut-off of stations right after I got my hands on the last working Sony AMAX Walkman in the city of Birmingham back in the late 90s. Somewhere on a minidisc (speaking of obsolete tech) I have an aircheck of "Legends 1260 WLGD" in Birmingham in stereo, recorded about a block from the tx site in the middle of the night. It sounded pretty good but shortly thereafter Crawford Broadcasting narrowed the audio to 5 kHz in preparation for HD and that was the end of stereo in Birmingham.

I always offer this link whenever we talk AM stereo because it's such a great bit of historical ephemera, but if you go to my website's WATV history page, you'll find a link to a recording on another site of them broadcasting in the Kahn-Hazeltine ISB stereo system, which was a competitor to Motorola's C-QUAM in the 80s. I think it sounds as good or better than the Japanese stations, not least of which is because it appears there is the full 15 kHz audio, pre-NSRC or whatever it's called.
 
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