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From: Dave Burnham <[log in to unmask]> Date: Fri, September 05, 2014 8:52 pm > Mike, what an informative fact-filled posting! One fact I > would question, (and that's a little gentler than "challenge"), > is the bandwidth of AM radio. I thought the rules limited a > station to a bandwidth of 10k, permitting frequencies up to > only 5k to prevent overlap into adjacent stations. db In the United States there never was a maximum AM bandwidth regulation until the 1990s. By the 12950s, AM transmitter spec. sheets showed 13 or 14 KHz audio bandwidths. Originally in 1934 the upper band between 1500 and 1600 had Hi-Fi allocations only at 1530, 1550, and 1570, and these stations were required to be at least 10 KHz. in audio but encouraged to be 15 KHz in audio bandwidth. that experiment lasted only 3 or 4 years but, yes, stations were set 10 KHz apart throughout the band. BUT for many decades the location and power allocations were such that there was a great distance between stations on adjacent frequencies (such as 570 being very far away from 560 and 580) and a little bit less distance between second adjacents (such as 550 and 590) but they were still far enough away that they did not interfere with each other. Thus a station could have a 12, 13, or even 14 KHz audio band width with no interference. Yes our 570 station was elbowing out to 583 or so, but there was no nearby station at 580, and any 590 station was of no consequence if they elbowed down to 577 with highs because they would be too weak, and besides, most radios only had a bandwidth of maybe 9 Khz except for some really super E.H. Scott oldies that had 13 or 14 Khz. Then came the 1970s and "short spacing". The FCC started reducing the physical distances between the second-adjacents. Good radios were starting to hear the splatters from these second-adjacents maybe 100 miles away. SO THE RADIO MANUFACTURES REDUCED THE BANDWIDTH OF THE RECEIVERS TO 5 KhZ AND THE SPLATTERS WENT AWAY. Meanwhile, ALL the Hi-Fi magazines stopped giving the bandwidth measurement in their reviews, so the manufacturers started to further reduce the bandwidth of their radios to 4.5, 4, or even 3.5. Stations noticed the dull sound coming out of the radios and boosted the highs in their stations -- used Aphex Aural Exciters to give their station a sizzle that would cut through the narrow bandwidth radios. This made the interference worse. the only way to solve the problem was to put in a 10KHz bandwidth regulation to eliminate 2nd adjacent interference because first adjacent interference was not yet a problem. But this was the era (error) of Ronald Raygun and he had put in place a "marketplace" guy as FCC Chairman, Mark Fowler. This foul guy said, sure, make it voluntary! If YOU want to cut at 10K, do it. Your competitors won't but who cares? It's the free marketplace. The idea was that if it became a law that the audio bandwidth would be cut at 9 KHz, then we can pass a law requiring the radio manufacturers to make their radios wideband again. Voluntary. The National Assoc of Broadcasters came out with an AMax standard to give certification to wideband AM radios. If you have a GE SuperRadio you have one of the three AMax radios ever certified. FINALLY, in the 1990s, just as Clinton was screwing up the business with a new Communications Act and the DMCA, his FCC DID pass a regulation called NRSC that reduced the bandwidth to 9 KHz. Hoping that radio manufactures would NOW build wideband radios. But that half of the law was never passed. I will leave out the AM-Stereo screw-up which was also happening at that time. I will only say that I had a chance to PUBLICLY chastise the entire Fowler FCC to their faces for screwing up AM-STEREO, and even got a nice write-up in Broadcasting magazine for doing it. Mike Biel [log in to unmask] Sent from my iPhone > On Sep 5, 2014, at 8:05 PM, Michael Biel <[log in to unmask]> wrote: > > This is such a long and complicated thread! David discusses at this > point earphone and speaker monitoring in the early years and then later, > mixing in with Tom's Cook materials. The early Western Electric > recordings at WE and then Victor/Columbia were monitored with the large > convex paper cone moving armature speakers. They were as large as > 36-inches. Electrical playback at home was headphones with crystal sets > because that is all it could drive. With tube sets the Magnavox horn > speakers were not bad, but there were some electromagnetic speakers like > the Peerless which supposedly had great bass response. I have not been > that enamored with the RCA speakers in their radios, yet I have heard > their phonographs sounding great. I have heard Atwater Kent radios from > 1929 and later with fantastic sound -- rich bass and wideband reception > on AM passing through highs that could be 7 or 8 KHz. > > > I read the Cook papers that Tom linked in his article and it is obvious > that he monitored with headphones because he recorded in remote > locations (seashore is in one picture) and was also right there with the > musicians in his remote folk and jazz recordings. You couldn't use > speakers, yet the same paper often discusses that the recordings would > be heard by speakers at home, not headphones. He discusses setting mics > 6 feet apart and the speakers six feet apart. He gives wavelength > figures as his reasoning. Yet he also talks about perspective heard in > headphones. Both David and I seem to agree that spaced pairs are not > what is meant as headphone binaural, having the mikes 6 inches apart is. > (I'm trying to find the post where David said something like this. I > don't want to put words in his mouth.) Cook does seem to indicate that > nobody but him will listen to his recordings on headphones. > > > David and several others gave their first stereo experiences which were > from the 1950s which is the same era as Cook. Same with me. In just > about every instance of demos there was an emphasis on hearing different > things on the two speakers, NOT fusing the sound to give you the > illusion of a phantom third channel or a continuous curtain of sound. I > heard a couple of tape demos in 56 and 57, and when my sister got a > Columbia stereo phono in early 59, even though the machine's speakers > became a center bass channel when the two satellite speakers were used, > I never heard a balanced soundstage. When I got my component set-up at > the end of the year as a Bar Mitvah present, my speakers were unbalanced > - the left channel was the Wollensak while the right channel was my mono > amp and corner-mount speaker. All difference and no center. Visiting a > friend who's father had a six foot wide stereo console, his demo to me > was some Command records. 'These babies are hand made, individually > hand cut." I knew from that he was crazy. "You better believe I expect > to hear different stuff coming out of the two sides -- I paid enough for > it!" > > > Even the industry was unsure of the fusing of a phantom center channel. > We now expect the solo vocalist to be in the center channel. MANY early > stereo records placed the singer off to one side or the other because > they did not expect home units to fuse a center channel. Exaggerated > separation was more important because cartridges only had 18-24 dB of > separation, and consoles -- which were very prevalent -- had speakers > too close together with a cabinet that was vibrated by both sets of > speakers. While this should have promoted a curtain of sound with a > center channel, it didn't. The emphasis was for L vs. R differences. > > > Tom is right when he says elsewhere that mono outsold stereo for many > years. I went to all the annual NY HiFi shows in the early 60s, and I > think it took till 1962 or 63 for the audiophile stereo market to kick > in. Columbia stuck with the multi-miked classical even then -- still > looking for separation. I think this all fits together -- you can't > separate the home playback equipment and the expectations of the average > consumer from the history of the recordings of the time. The listening > experience was different then. > > > > Mike Biel [log in to unmask] > > -------- Original Message -------- > Subject: Re: [ARSCLIST] Accidental stereo (again) > From: DAVID BURNHAM <[log in to unmask]> > Date: Fri, September 05, 2014 10:58 am > To: [log in to unmask] > > Thanks, Tom, interesting insight. I have no idea if early electrical > recording sessions were monitored on earphones or loudspeakers, but > certainly crystal sets always used an earphone. I assume, (and I might > be wrong), that electronic audio was born as a complete package - > pre-amp, power amp, electro-dynamic speaker, (one using an electro > magnet, not a permanent magnet), microphones, wires, cutting heads and > phono cartridges. > > My comment about earphone listening was referring to listening to > earphones for higher quality sound reproduction, without the > interference of the bad acoustics in most home listening environments > and to reproduce the early binaural recordings. I don't recall any > referrence to high quality head sets before the late '50s. I remember > all sorts of stereo demonstrations at the CNE, (Canadian National > Exhibition), both pre and post the development of the single groove > stereo disc, but they invariably used ear phones, (not a headset), where > you actually had to hold each ear phone to each ear. I think in the > earliest days of electronic reproduction the sound from speakers or ear > phones was pretty wretched. I have heard speakers from the '20s, > (speakers mounted in a round cookie tin shaped enclosure with grill > cloth on the front, or a long swan-neck shaped horn physically connected > to what is essentially an ear phone and they don't sound as good as > decent > acoustic reproduction. > > db > > > On Friday, September 5, 2014 7:13:15 AM, Tom Fine > <[log in to unmask]> wrote: > > >> >> >> Hi Dave: >> >> As I understand the history, the original listening device for > electronically-generated audio was >> "earphones." Going back to crystal radios. I think the original > iteration was exactly what was used >> for the earpiece on early telephone sets (a carbon device?). Then came > what were essentially >> earphones at the end of horns, the first "loudspeakers," so radios > could be heard by several people >> at the same time. Then came field-coil speakers. Then came dynamic > speakers. >> >> I think location recording was monitored with "earphones" throughout > the mono electrical-recording >> era, although playback from lacquers may have involved speakers > (probably not until the 1940s, but I >> might be wrong about that). >> >> Headphones kept evolving for professional audio and broadcasting all > along, but I think they hit a >> note with consumers in the stereo era. Remember the baby boomer kids > with big Koss closed-back >> 'phones in 70's college dorm rooms? For my generation, headphones were > part of the Walkman, so they >> were a big part of our youth (people forget how liberating > super-portable "personal stereo" was, >> given that the previous choice was boomboxes, which weren't as > tolerated in suburban homes as they >> were on inner city streets, plus nothing enhanced that alienated > suburban white kid teenage thing >> more than putting on the Walkman 'phones, cranking up the punk rock > and sneering! ;) ). When the >> iPod came along, we got to a new phase of ultra-portability, now heard > through earbuds or >> bass-enhanced Beats-style phones. >> >> To my ears, the worst music for headphone listening is hard-panned > early stereo like Blue Note >> stereo mixes or stereo Beatles mixes pre-Abbey Road. Old "binaural" > material works fine. I suspect, >> aside from collector-fetish cache, one of the reasons many mono mixes > of popular and jazz titles are >> being reissued in modern times has to do with earbud/Beats listening. > The mono sounds superior in >> that setting vs the hard-panned stereo. >> >> -- Tom Fine >> >> ----- Original Message ----- >> From: "DAVID BURNHAM" <[log in to unmask]> >> To: <[log in to unmask]> >> Sent: Thursday, September 04, 2014 11:05 PM >> Subject: Re: [ARSCLIST] Accidental stereo (again) >> >> >>> I just read most of the information in your attachments, Tom; I would > love to hear the Reginald >>> Foort Organ record that is shown. I did not quite understand how > Cook's twin groove records >>> provide superior mono compatibility because if you play either groove > you'll only get one channel, >>> and if you use a Cook stereo arm to play both channels and mix them > to mono, the best you'll get is >>> as good as a single 45/45 groove but most likely a microscopic > misallignment of the arms will cause >>> a phase shift. The author does say, (I don't know if this is modern > writing or historic), that >>> binaural cannot be properly listened to using speakers because of > both channels getting to both >>> ears - exactly what we were discussing. >>> >>> I'm not sure but I don't believe earphones were ever used to listen > to music before the >>> introduction of Stereo. Mono sounds very poor on headphones - the > source of sound is in the >>> middle of your head. So the message I get from this is that in the > earliest days of "Stereo" >>> recording the intent was that it should be listened to on earphones. >>> >>> db >>> >>> >>> On Thursday, September 4, 2014 5:14:48 PM, Tom Fine > <[log in to unmask]> wrote: >>> >>> >>>> >>>> >>>> I am pretty sure (based on photos and somewhat sketchy descriptions > in magazine articles) that >>>> Cook's early stereo recordings were made with 2 widely spaced mics > onto a Magnecorder >>>> staggered-head >>>> 2-track. He is always shown monitoring with headphones. To me, this > is clearly "binaural" >>>> recording >>>> methodology, which will only sound good through headphones. On > speakers, there will be a very weak >>>> center, unless the speakers are spaced at headphone distance (ie > right next to each other). >>>> >>>> Now, I don't know whether Cook changed his setup or method when he > came up with the dual-channel >>>> cutting and playback systems. >>>> >>>> Here is a bunch of material on Emory Cook that I gave to Chris > Sanchez to write up in his >>>> Preservation Sound blog: >>>> http://www.preservationsound.com/?p=5695 >>>> and >>>> http://www.preservationsound.com/?p=6240 >>>> >>>> -- Tom Fine >>>> >>>> >>>> ----- Original Message ----- >>>> From: "Michael Biel" <[log in to unmask]> >>>> To: <[log in to unmask]> >>>> Sent: Thursday, September 04, 2014 4:19 PM >>>> Subject: Re: [ARSCLIST] Accidental stereo (again) >>>> >>>> >>>>>> On 04/09/2014, Tom Fine wrote: >>>>>> I think, in the early stereo days, only Emory Cook consistently >>>>>> recorded true "binaural" tapes, in other words those designed to > be >>>>>> listened to through headphones only. >>>>> >>>>> Are you sure of that. My experience is exactly the opposite. Cook >>>>> produced exactly one CD. It was a demonstration of a re-processing >>>>> technique, and you had to sign an agreement not to copy it in > order to >>>>> get it. the first track is a female blues singer. For about 30 > seconds >>>>> the small combo is heard on the right track in mono with nothing > on the >>>>> left channel until she starts to sing. It is like those Elvis and >>>>> Beatles tapes meant for mix-down, but this is what Cook chose to > start >>>>> his demo CD. >>>>> >>>>> Because his dual groove system used a radial playback arm, he knew > there >>>>> would be phase shift problems. Plus the two bands were cut with >>>>> different EQ curves. Thus it was vital that there be as little > "center" >>>>> channel as possible, that there be nothing that was strongly heard > in >>>>> both channels. I've got about 20 discs but no arm for them. When > he >>>>> did come out with single-groove stereo LPs the separation was > extreme. >>>>> Remember, this is the guy who did the atmospherics albums with two > radio >>>>> receivers hundreds of miles apart. When he recorded the folk > groups he >>>>> stuck two mikes down in front of two different parts of the group. > I >>>>> don't think he separated them into two rooms like RCA did that > time when >>>>> they split a group into two studios a city block apart, but > listening to >>>>> these with headphones leaves a hole in the middle where your head > used >>>>> to be. Maybe some of his classical recordings used mikes close >>>>> together, but that was a minority of his catalog. >>>>> >>>>> Mike Biel [log in to unmask] >> >> >>