First Time I Heard Stereo At Dr. Monroe's House 

I told my wife this story the other day, and it's kind of fun.

When I was about 8 or 9 (late 50s), I heard "stereo" for the first time.

We were visiting Dr. Jerry (Gerry? / Gerald?) Monroe in Dallas. He was a bigwig in R&D at Chance Vought, I think my dad worked with or for him. Anyway, my Dad had told me that he had this great hifi that had two speakers and two channels ("one for each ear, sort of") that I really should hear.

I remember he had two speaker enclosures with arrays of small speakers, all the same size... I believe they were about 5-inch round speakers, and that they had blue cones - and I think gold middles. I think they were in 5x4 arrays on each side or something like that. I'd never seen anything like that, and they looked pretty formidable. I believe he had built the enclosures himself.

He had his turntable, amps, and controls near the back of the room on the left hand side as you came in. The speakers were at the far end of the room. I was told to go sit in the exact middle between the speakers, and they put on some classical piece. My first impression was that the sound was not coming from the speakers at all, but in front of me... but I walked around the room to convince myself the speakers were actually delivering the sound. Someone told me that I could hear where the instruments in the orchestra were if I listened carefully, and gradually I started to pick them out a little bit.

The sound was wonderful, but the funny part of the story was the next part.

First I have to back up to when I was a lot younger and had my own little tabletop phonograph with my "kiddie" 78RPM records ("Winnie the Pooh", and the like). I had discovered that I could hear the records (not very well) if I used my fingernail while the turntable was spinning. So there's a physical groove, and the sound is "etched" in the groove. I think by this time in my life, I had seen sound represented on an oscilloscope, so I had some idea about frequencies and such.

Also, a few years prior, my grandmother had bought us a non-stereo "hifi" that sounded *so* much better than my tabletop phonograph, that I understood a little about sound quality. I remember hearing "stuff" in the nutcracker when we first got the "hifi" that I had never heard before, and listening to it over-and-over. (These were 33 1/3 RPM records, of course).

Well, anyway, at Dr. Monroe's, there were obviously two sets of speakers, and obviously "different stuff" was coming out of each side... so I figured the turntable would be somehow significantly different - there should be either two records, or two needles, or two somethings. (going back to my fingernail analogy). When I looked at the turntable, I saw only one record, one needle... so I was feeling a bit confused.

So I asked Dr. Monroe the question (more or less)... how can you have only one needle putting out different parts of the music into each speaker?" I may have asked something like "Don't you need two needles?". I remember the answer... first of all, he got kind of a startled look on his face (I was only 8 or 9)... and he took a while to answer. I think he may have asked my dad "How am I going to explain this?" But he gave it a go... He said something along the lines of "Well... this isn't exactly how it works, but it's close." (I thought it was cool that he set it up like this.) "Imagine that the groove has bumps at the bottom for one side of the music, and bumps along the side for the other part of the music. So when the needle moves up and down, that causes the pickup to send the signal for one channel, and when it moves from side-to-side, that is the signal for the other channel." I think he drew a picture of the cross section of the groove as he was explaining all this. I guess it's lucky they weren't doing time division multiplexing or anything like that! Analog was so intuitive.

I think the actual encoding of the two channels are offset by 90 degrees, but is on a 45 degree slant or something of the sort, with two magnetic pickups, but I've never been curious enough to dig out that level of details... at age over 50 now, I'm still pretty satisfied with Dr. Monroe's "general idea". As long as I can hook up the 4 wires and have it sound OK, I'm happy.

I built my first stereo (sort of) with a turntable I got a Zacks in Palo Alto. I installed it into a monster Zenith console radio I had (which had previously had a 78RPM-only turntable - in retrospect, that was probably a bad idea - the old turntable would probably have antique value today). I put a coax wire with an RCA plug on it on one side and ran it to an old blond (B&W of course!) Silvertone TV set I had. On this TV you could plug in a phonograph signal and turn a slide switch on the back of the TV chassis and - instant amplifier for the left channel. (When you turned the switch, I think it turned the picture off. I don't know how many consumers ever actually used this feature - today it strikes me as kind of odd that it was there at all, but perhaps it helped repair people isolate problems with the audio...) The right channel just ran through the old Zenith console radio. None of this was that "hifi", (the Zenith had better sound) but it was "Stereo", so at least I could play stereo records.




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