Just for general info. >
the SR stood for "Spectral Recording" > where the format used multi-band compression & expansion with advanced RMS detection.
It is sort of a shame that Dolby S, for domestic use only appeared at the very 'tail-end' of the cassette formats use >
basically - no one got to hear it !
Hi Audio>X,
Yes, I guess. I used a consumer version set up for "flat" machines. Teac and outboard dBx products played nicely together, but I also calibrated the dBx decoders and encoders. I used a Teac V-800X back then. Curiously you couldn't align both the Dolby and dBx, I choose dBx as a result. I probably could have figured out the problem, but it wasn't worth the effort.
Yes, it is too bad Dolby S came out as late as it did, it was more expensive to implement. Dolby B chips had high distortion, which is reason #1 I didn't like it. You were further ahead with no Dolby noise reduction for natural sounding tapes than using Dolby B. In pro, a Dolby SR module was very expensive and you used it on a track-by-track basis. It would be terribly expensive to load up 46 tracks (two 24 track machines synced together), or even 23 tracks.
That's the problem with equipment comparisons. No one made sure all systems were properly aligned. Comparisons were worthless as a result.
I thought the decoders for LPs were adjustable. I had never seen a dBx decoder for LP, but did have an album or two that I used the dBx in the tape deck. Yes, you had to sett he levels carefully or it would "pump and breathe".
Yes, I guess. I used a consumer version set up for "flat" machines. Teac and outboard dBx products played nicely together, but I also calibrated the dBx decoders and encoders. I used a Teac V-800X back then. Curiously you couldn't align both the Dolby and dBx, I choose dBx as a result. I probably could have figured out the problem, but it wasn't worth the effort.
Yes, it is too bad Dolby S came out as late as it did, it was more expensive to implement. Dolby B chips had high distortion, which is reason #1 I didn't like it. You were further ahead with no Dolby noise reduction for natural sounding tapes than using Dolby B. In pro, a Dolby SR module was very expensive and you used it on a track-by-track basis. It would be terribly expensive to load up 46 tracks (two 24 track machines synced together), or even 23 tracks.
That's the problem with equipment comparisons. No one made sure all systems were properly aligned. Comparisons were worthless as a result.
I thought the decoders for LPs were adjustable. I had never seen a dBx decoder for LP, but did have an album or two that I used the dBx in the tape deck. Yes, you had to sett he levels carefully or it would "pump and breathe".
Yum!
I never liked it for some reason. Perhaps that was entirely due to mismatch between whatever deck I used to record at the Olson's store and my Concord car cassette player I had back at the end of my Uni days.
My first cassette recorder, a TEAC which I had in the last couple years of high school didnt even have Dolby - couldnt afford it. I liked to take the bottom cover off things and noticed the belt pulley had two slots, one larger diameter than the belt was on. I somehow found a small Allen key and flipped it - then all my recorded tapes ran a smidge faster; 6/5X. Clever / idiotic way for a high schooler to get it to sound a bit better, he thought. Probably threw everything off - nevermind using BASF Chromedioxid tapes on a machine not setup for that.
The Concord was the best deck back then. Sendust heads by the way. I still have my HPL-200.
Most tape machines were not calibrated very well. So Dolby wouldn't have a hope of working properly.
Oh No! CrO2 tapes were "lapping tape in a box". We could tell easily when someone used real CrO2 tape, it tore the heads right out of cassette decks. TDK and Maxell were Cobalt. Normal BASF caked everything in sight will your oxide layer. Metal tape was even more vicious to tape heads.
Most tape machines were not calibrated very well. So Dolby wouldn't have a hope of working properly.
Oh No! CrO2 tapes were "lapping tape in a box". We could tell easily when someone used real CrO2 tape, it tore the heads right out of cassette decks. TDK and Maxell were Cobalt. Normal BASF caked everything in sight will your oxide layer. Metal tape was even more vicious to tape heads.
I recall vaguely that Technics “feature,”(although I do not remember if it was a dBX chip). It was not noise reduction but rather a form of range expansion: the assumption being that between the effects of compression applied at mixing or mastering processes, as well as tape compression in the process of transfer to non-high MOL cassette tape, the upper peak levels of the program were less than the original sound in the studio before capture by the recording process. The switch would expand the upper levels of the signal to “restore” the original peaks. IMO a dubious proposition at best.
Did Carver have such a system? I also remember the Burwen professional system of range expansion, or was it noise reduction? A lot of innovation was happening in the 60s and 70s.
Did Carver have such a system? I also remember the Burwen professional system of range expansion, or was it noise reduction? A lot of innovation was happening in the 60s and 70s.
Hi Halauhula,
You may be thinking of ANRS (?) possibly? It didn't require encoding and it was a way to avoid the high Dolby noise reduction fees (license). It sort of worked and cheaper equipment jumped all over it.
Carver, to the best of my knowledge, did a bunch of odd things with names that didn't really address what they did. Drove me nuts as customers were always asking about whatever feature. The feature description was misleading (like magnetic field amplifier). DTL (digital time lens) and ACCD (asymmetrical charge coupled detector) along with others are great examples.
You may be thinking of ANRS (?) possibly? It didn't require encoding and it was a way to avoid the high Dolby noise reduction fees (license). It sort of worked and cheaper equipment jumped all over it.
Carver, to the best of my knowledge, did a bunch of odd things with names that didn't really address what they did. Drove me nuts as customers were always asking about whatever feature. The feature description was misleading (like magnetic field amplifier). DTL (digital time lens) and ACCD (asymmetrical charge coupled detector) along with others are great examples.
Autocorrelator. I assume it was a bunch of bandpass filters each with an RMS detector driving a VCA. If no signal in a particular band below a threshold, the VCA shuts off and any noise coming from within that band gets muted.
I recall it actually worked and could make my nastiest tapes sound OK again. Nasty, being recorded from cassette to RTR and back to cassette - with nothing adjusted nor calibrated.
I never got the marketing name for that device/function. I even looked it up all those years ago and its something like a signal, multiplied by the same signal but with a slight time delay and that product integrated. How that translates into a bunch of bandpass filters each with a squelch circuit is beyond me. Sounds cool and looks good in black cursive, screen printed onto a sharp looking brushed aluminum front panel!
Hi jjasniew,
Yes. It is a complicated circuit. Mostly, Carver add-on circuits would sum the left and right after the attack (or high frequencies) to preserve the stereo sound. These circuits could be an entire PCB onto themselves. The devil was in the details.
We never worried about exactly how each worked. We got the general idea and just fixed them. Typical issues were a loss of signal or distortion, the very odd time - noise. Just normal component failure stuff. The names of the circuits were annoying, so I really didn't want to know the fine details. I classified them as gimmicks. They mostly dealt with poor quality signals, or to make a CD sound more like a record (DTL). Sonic Hologram was another.
Yes. It is a complicated circuit. Mostly, Carver add-on circuits would sum the left and right after the attack (or high frequencies) to preserve the stereo sound. These circuits could be an entire PCB onto themselves. The devil was in the details.
We never worried about exactly how each worked. We got the general idea and just fixed them. Typical issues were a loss of signal or distortion, the very odd time - noise. Just normal component failure stuff. The names of the circuits were annoying, so I really didn't want to know the fine details. I classified them as gimmicks. They mostly dealt with poor quality signals, or to make a CD sound more like a record (DTL). Sonic Hologram was another.
I thought to 'wrap-up' my posting about noise reduction it would be good to list all the systems that I am aware of >
Some very early entry-level cassette decks EG. AWA, Sharp and Hitachi offered a simple High Cut switch simply labeled noise reduction or hiss cut.
This was of course the simplest noise reduction, and it only worked on playback. [ did nothing to recording ]
Phillips, who invented the cassette, developed DNL = Dynamic Noise Limiter. It was a more advanced of the above. Interestingly it was included
with the Nakamichi 1000.
Dolby > A , B , C , S & SR . The brief I read on Dolby S said it was an improvement on Dolby C, and had a 'better sound' in the case of non-decoding.
DBX (type 1 & 2 ?)
JVC developed their own system ANRS, and later Super ANRS = Automatic Noise Reduction System. Both versions did use encoding & decoding.
ANRS was actually more similar to DBX than it was to Dolby B.
Fairly late in the piece, Toshiba released ADRES = Automatic Dynamic Range Expansion System. Not only in a cassette deck, but also as a stand-alone
2 Channel encoder/decoder. I actually owned the '1 rack space unit' > Brilliant for old 'hissy' 2 track reel to reel machines. It used large dedicated chips.
We also had [ as mentioned ] the Autocorrelator device > but once again it was purely a playback devise with no encoding.
Finally, I came across a Luxman DAT machine that had switchable pre-emphasis/de-emphasis that was a form of Noise Reduction.
PS.
Just imagine how many 'incompatibilities' can exist outside of a dedicated tape machine. Even NAB vs IEC was enough for some people 😕
Some very early entry-level cassette decks EG. AWA, Sharp and Hitachi offered a simple High Cut switch simply labeled noise reduction or hiss cut.
This was of course the simplest noise reduction, and it only worked on playback. [ did nothing to recording ]
Phillips, who invented the cassette, developed DNL = Dynamic Noise Limiter. It was a more advanced of the above. Interestingly it was included
with the Nakamichi 1000.
Dolby > A , B , C , S & SR . The brief I read on Dolby S said it was an improvement on Dolby C, and had a 'better sound' in the case of non-decoding.
DBX (type 1 & 2 ?)
JVC developed their own system ANRS, and later Super ANRS = Automatic Noise Reduction System. Both versions did use encoding & decoding.
ANRS was actually more similar to DBX than it was to Dolby B.
Fairly late in the piece, Toshiba released ADRES = Automatic Dynamic Range Expansion System. Not only in a cassette deck, but also as a stand-alone
2 Channel encoder/decoder. I actually owned the '1 rack space unit' > Brilliant for old 'hissy' 2 track reel to reel machines. It used large dedicated chips.
We also had [ as mentioned ] the Autocorrelator device > but once again it was purely a playback devise with no encoding.
Finally, I came across a Luxman DAT machine that had switchable pre-emphasis/de-emphasis that was a form of Noise Reduction.
PS.
Just imagine how many 'incompatibilities' can exist outside of a dedicated tape machine. Even NAB vs IEC was enough for some people 😕
Hi Audio>X,
Nakamichi incorporated the best noise reduction systems, always. Early adopters. The old 1000 is a beast, but cutting edge for the time. The 1000 ZXL (and limited) are fantastic machines. Update the electronics and you have a giant killer for today. I would update the Dolby section as a primary upgrade, then the head amp. Other improvements would gain some increases in performance, but the head amp and Dolby are the best places to start.
You brought back some memories. DNL is a dim memory, I remember the JVC systems, never heard of the Toshiba system until now.
One noise reduction system also played with the bias on tape. I can't remember if it was Dolby C or Dolby S. Dolby A and Dolby SR were purely recording studio systems, not normally offered to the public.
dBx was also part of the VCR stereo format, not on the linear tracks but encoded on the rotary head track. Now I recall the type 1 and type 2 dBx systems. Back then, licensing fees for dBx and Dolby were crushing. THX then followed the same business model. Consumers did not benefit from the inflated fees for these systems. I don't imagine anything has changed for certification to a "standard".
Digital preemphasis was a standard both on DAT and CD formats. Once set in record it set a digital flag, from there it was automatic. They also set a copy protection flag in those machines (in one DAT you only had to destroy a signal diode to defeat it).
Nakamichi incorporated the best noise reduction systems, always. Early adopters. The old 1000 is a beast, but cutting edge for the time. The 1000 ZXL (and limited) are fantastic machines. Update the electronics and you have a giant killer for today. I would update the Dolby section as a primary upgrade, then the head amp. Other improvements would gain some increases in performance, but the head amp and Dolby are the best places to start.
You brought back some memories. DNL is a dim memory, I remember the JVC systems, never heard of the Toshiba system until now.
One noise reduction system also played with the bias on tape. I can't remember if it was Dolby C or Dolby S. Dolby A and Dolby SR were purely recording studio systems, not normally offered to the public.
dBx was also part of the VCR stereo format, not on the linear tracks but encoded on the rotary head track. Now I recall the type 1 and type 2 dBx systems. Back then, licensing fees for dBx and Dolby were crushing. THX then followed the same business model. Consumers did not benefit from the inflated fees for these systems. I don't imagine anything has changed for certification to a "standard".
Digital preemphasis was a standard both on DAT and CD formats. Once set in record it set a digital flag, from there it was automatic. They also set a copy protection flag in those machines (in one DAT you only had to destroy a signal diode to defeat it).
I recall a friend, while sitting around in his living room listening, said linear encoding of music was illogical. He said the music signal should first be run through a log amp, then to the linear encoder. Upon playback it goes through an anti-log amp. I've always wondered if that idea had any merit...
Around 1976 I built an SWTP audio expander/compressor unit. I didnt know how to use it at the time, but read elsewhere (Audiokarma) others achieved noise reduction goodness with the device. I used it mostly for general dynamic range expansion, usually to excess too, as that was sort of a theme for me back then. As ridiculous as I could make things sound, I remember it got people's attention.
Around 1976 I built an SWTP audio expander/compressor unit. I didnt know how to use it at the time, but read elsewhere (Audiokarma) others achieved noise reduction goodness with the device. I used it mostly for general dynamic range expansion, usually to excess too, as that was sort of a theme for me back then. As ridiculous as I could make things sound, I remember it got people's attention.
As a layperson, using a log amp and then a linear encoder in series at the mastering stage is asking for trouble in terms of repeatability and accuracy across millions of consumer units when decoding.
Perhaps you and Anatech can comment on the effects of this at the front-end, in the mastering stage, and the possible concerns about calibration.
Perhaps you and Anatech can comment on the effects of this at the front-end, in the mastering stage, and the possible concerns about calibration.
Hi jjasniew, Halauhula,
Anything you do to a signal that is non-linear is critically dependent on the signal remaining at exactly the same levels and frequency response when presented to the decoding stage. Any deviation at all will result in mistracking of the decoding process. Generally not good. For obvious reasons, the more effective processes involve more pre-emphasis or compression. This magnifies any errors in between encode and decode. Also, the encoding and decoding must be exactly complimentary. So for something like multiband processing, the filter turnover frequencies and slopes must also be the same. Same for any logarithmic ratio (complimentary).
So, if everything is perfect ... Compression on record is the basic scheme. That places quiet passages well above the noise floor, and loud passages away from saturation of the tape. This then makes the dynamic range wider (dropping tape hiss) and reduces distortion generated by high levels of modulation during recording (mixing with the bias current, AM modulation). When you play back, the system will decrease background hiss and increase the peak levels. You will hear the background hiss varying (described as pumping or breathing). This is unavoidable.
It comes down to a balance of noise and varying background noise for some people. These effects are lower with less effective noise reduction, makes sense when you think of it. The other ways to lower hiss and allow higher signal levels are increasing the track width, and increasing the tape speed. Increasing track width also increases media (tape) costs, increasing speed also increases cost, but also moves something called "head bumps" into the more audible range. These are variations in frequency response related to head gap width and speed. Studer machines EQ these out. You can see then that a 1/2 track machine running at 30 ips would sound amazing (they really do), but the cost of the tape is shockingly high. Even a 1/2 track running at 15 ips sounds fantastic, but expen$ive as heck. You don't turn a 1/2 track tape over, you rewind and play it off storing it "tails out". I had a Teac BR-20, beautiful sounding machine.
In the recording studio, any major, decent one anyway, the tech checks azimuth and PB levels / response, then calibrates the machine to the tape used and records calibration tones. Noise reduction is done on a track by track basis (these modules are rented to the client and expensive). Choices are typically nothing, Dolby A and Dolby SR. If you are talking about Studer machines in good repair, encode-decode isn't too much of a problem. Drum tracks and similar go to the outside, typically no noise reduction. One outside track is typically time code. You'll find higher value sounds (vocals and things) to the center tracks. When mixing down to the mastering machine (stereo) they might use noise reduction. These days it goes down to digital storage, as many tracks as needed, like a surround mix for example.
Sounds recorded on the multitrack machines are called "bed tracks". They may have effects units process these before recording, or they can be run through various effects machines and laid down on another track if desired. Then they are played back, whatever tracks they want through a mixing console and "mixed down" to the final master tape. That's the old days, not entirely certain of the specifics today. I do know that multichannel stuff will go through a surround processor and saved to whatever format they are using.
Those are the basics anyway.
Anything you do to a signal that is non-linear is critically dependent on the signal remaining at exactly the same levels and frequency response when presented to the decoding stage. Any deviation at all will result in mistracking of the decoding process. Generally not good. For obvious reasons, the more effective processes involve more pre-emphasis or compression. This magnifies any errors in between encode and decode. Also, the encoding and decoding must be exactly complimentary. So for something like multiband processing, the filter turnover frequencies and slopes must also be the same. Same for any logarithmic ratio (complimentary).
So, if everything is perfect ... Compression on record is the basic scheme. That places quiet passages well above the noise floor, and loud passages away from saturation of the tape. This then makes the dynamic range wider (dropping tape hiss) and reduces distortion generated by high levels of modulation during recording (mixing with the bias current, AM modulation). When you play back, the system will decrease background hiss and increase the peak levels. You will hear the background hiss varying (described as pumping or breathing). This is unavoidable.
It comes down to a balance of noise and varying background noise for some people. These effects are lower with less effective noise reduction, makes sense when you think of it. The other ways to lower hiss and allow higher signal levels are increasing the track width, and increasing the tape speed. Increasing track width also increases media (tape) costs, increasing speed also increases cost, but also moves something called "head bumps" into the more audible range. These are variations in frequency response related to head gap width and speed. Studer machines EQ these out. You can see then that a 1/2 track machine running at 30 ips would sound amazing (they really do), but the cost of the tape is shockingly high. Even a 1/2 track running at 15 ips sounds fantastic, but expen$ive as heck. You don't turn a 1/2 track tape over, you rewind and play it off storing it "tails out". I had a Teac BR-20, beautiful sounding machine.
In the recording studio, any major, decent one anyway, the tech checks azimuth and PB levels / response, then calibrates the machine to the tape used and records calibration tones. Noise reduction is done on a track by track basis (these modules are rented to the client and expensive). Choices are typically nothing, Dolby A and Dolby SR. If you are talking about Studer machines in good repair, encode-decode isn't too much of a problem. Drum tracks and similar go to the outside, typically no noise reduction. One outside track is typically time code. You'll find higher value sounds (vocals and things) to the center tracks. When mixing down to the mastering machine (stereo) they might use noise reduction. These days it goes down to digital storage, as many tracks as needed, like a surround mix for example.
Sounds recorded on the multitrack machines are called "bed tracks". They may have effects units process these before recording, or they can be run through various effects machines and laid down on another track if desired. Then they are played back, whatever tracks they want through a mixing console and "mixed down" to the final master tape. That's the old days, not entirely certain of the specifics today. I do know that multichannel stuff will go through a surround processor and saved to whatever format they are using.
Those are the basics anyway.
I remember reading that 30ips recording has “head bumps” but the person mentioning them did not further explain what this phenomenon is. The gist of his position was that the issues with 30ips recording unless tape machine is excellent and properly calibrated, and good Q tape is used, it is not going to result in a substantially better recording than 25ips. Which means, in other words, “you gotta do it right,” as with everything else.
I have never heard 30ips tapes being played back, but I was told that the tracking tapes for Michael Hedges album, Aerial Boundaries, was recorded at 30ips. I’m trying to remember what few other albums were recorded at 30ips. My recollection is that even Mercury Living a presence was mostly 25ips tape, or perf magnetized film base run through the special recorder but at a speed not known to me. There was a book on Mercury Living Presence but it is OOP.
No ordinary person can afford tracking at 30ips!
I have never heard 30ips tapes being played back, but I was told that the tracking tapes for Michael Hedges album, Aerial Boundaries, was recorded at 30ips. I’m trying to remember what few other albums were recorded at 30ips. My recollection is that even Mercury Living a presence was mostly 25ips tape, or perf magnetized film base run through the special recorder but at a speed not known to me. There was a book on Mercury Living Presence but it is OOP.
No ordinary person can afford tracking at 30ips!
That was Dolby HX Pro.
It wasn't actually a noise reduction system, but a rather clever & nifty 'anti HF tape saturation circuit' that was developed by Dolby.
The way it worked was > in the absence of significant low frequency signal 'at a given point in time' and where there was HIGH amounts of
very high frequencies, it would 'cleverly' reduce tape-bias by a degree to help reduce high frequency tape saturation.
Of coarse, this was a 'record function' only.
In a way, you've really got to hand it to a number of companies for their tenacity to change an originally 'Dictaphone format' into true HiFi 🙂
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Hi Audio>X,
Thanks for reminding me, I couldn't put my finger on that system. Calibrated many machines using that system. Ingenious to combine Dolby with bias manipulation.
Oh, for sure! Cassette tape was intended for "Dictaphones" in office use, speech only. Any court proceedings or groups recording minutes or notes used them. The fact tape manufacturers and cassette deck manufacturers got together and produced what we have is amazing to me. 8-track tapes were better at the time, and open reel or record albums were the only HiFi sources considered.
I have a brand new Marantz PMD-360 still in the box, and had a Superscope CD-330. Those were 3-head home machines in portable form, but they added a counter-rotating flywheel so moving it wouldn't change the speed. Really, really good machines. I should sell the new one, never even unpacked.
The state of audio today would be mind-blowing to the audiophile of the 1920's and 1930's (they did exist).
Thanks for reminding me, I couldn't put my finger on that system. Calibrated many machines using that system. Ingenious to combine Dolby with bias manipulation.
Oh, for sure! Cassette tape was intended for "Dictaphones" in office use, speech only. Any court proceedings or groups recording minutes or notes used them. The fact tape manufacturers and cassette deck manufacturers got together and produced what we have is amazing to me. 8-track tapes were better at the time, and open reel or record albums were the only HiFi sources considered.
I have a brand new Marantz PMD-360 still in the box, and had a Superscope CD-330. Those were 3-head home machines in portable form, but they added a counter-rotating flywheel so moving it wouldn't change the speed. Really, really good machines. I should sell the new one, never even unpacked.
The state of audio today would be mind-blowing to the audiophile of the 1920's and 1930's (they did exist).
A high school friend's oldest brother was a "Lanier" business machine salesman. He gave me a few blank cassette tapes, which sounded like nothing else, for sure some iron oxide formulation. They were better than nothin' left to use.
Speaking of Antique, I'm almost 70. Who remembers late 60's early 70's growing up neighborhood families that had audiophile equipment?
It seemed pretty rare, like most people just werent interested. I used to follow my friend as he collected for his paper route and got to peer in the various homes he collected from. The biggest house on the street had a color TV, but no Altec Valencias... Which I would have noticed.
Mr Esch two doors down was a Harmon Kardon fan and bought a receiver and KLH speakers. Mt Hamilla had a large Grundig console and bought an equally large Sansui receiver, which my buddy said no one was allowed to touch. Didnt recall the speakers. Mr Cuoco next door was a part time TV repair person and gifted me the guts from some large GE console - a big mono tuner preamp connected to a power amp power supply via an umbilical. He kept the two 12" speakers and never did anything with them.
Even the guy who gave me a Marantz model 7 (!) wasnt really all that interested in audio. Else I suspect that bit would have been "in use". ;')
It seemed pretty rare, like most people just werent interested. I used to follow my friend as he collected for his paper route and got to peer in the various homes he collected from. The biggest house on the street had a color TV, but no Altec Valencias... Which I would have noticed.
Mr Esch two doors down was a Harmon Kardon fan and bought a receiver and KLH speakers. Mt Hamilla had a large Grundig console and bought an equally large Sansui receiver, which my buddy said no one was allowed to touch. Didnt recall the speakers. Mr Cuoco next door was a part time TV repair person and gifted me the guts from some large GE console - a big mono tuner preamp connected to a power amp power supply via an umbilical. He kept the two 12" speakers and never did anything with them.
Even the guy who gave me a Marantz model 7 (!) wasnt really all that interested in audio. Else I suspect that bit would have been "in use". ;')
Most people had console sound systems, some stereo. My father was very into stereo, so I was introduced at a tender age and apparently always loved music. He bought me a Fisher FM100 and Stereo 400 preamp before I was even 10. Still have them.
In high school, most of my friends families had nice stereo systems. Thorens turntables (we had a TD-160, as did most). It seemed normal. Friends at high school taking electronics were building stereo amplifiers and such. I did when I attended Ryerson Polytechnic.
Do you remember at night walking up the street after dark with your friends? A blue glow meant they had black and white TVs, green was colour TV. Colour was a big thing in the 60's
I'm only 66, so a youngster. Those were really fond memories. I was given scrap electronics, mostly TV's. That is where most of my parts came from, including some really nice raw speakers.
In high school, most of my friends families had nice stereo systems. Thorens turntables (we had a TD-160, as did most). It seemed normal. Friends at high school taking electronics were building stereo amplifiers and such. I did when I attended Ryerson Polytechnic.
Do you remember at night walking up the street after dark with your friends? A blue glow meant they had black and white TVs, green was colour TV. Colour was a big thing in the 60's
I'm only 66, so a youngster. Those were really fond memories. I was given scrap electronics, mostly TV's. That is where most of my parts came from, including some really nice raw speakers.