The death of audio pioneer Amar Bose brings back the memory of something that was a passion of mine during the 1970’s–audio equipment. (The legacy of that passion may be seen in my digitisation technique for some of the albums on my music pages). It may seem strange now but the quest for analogue perfection was a serious business for many of us.
“High fidelity”, the catchphrase for the 1950’s and 1960’s, was a relative term, and most of the equipment produced during the era didn’t quite make it. A good example is the BSR turntable to the right. They were cheap and appeared in millions of “stereo systems”, all the while helping the UK’s economy, struggling under post-World War II socialism and trade unions. (Garrard, from the same shores, were better). But the ceramic cartridges (the thing that actually faced the vinyl record) were not only poor transducers of the groove modulations to electrical signals, they pushed back against the grooves and wore them out, which is a major reason some of the albums on this site sound so bad. (The photo shows a moving magnet magnetic one, a major improvement in all respects.)
Once the signal was out of the turntable, amplifying it was probably the best part of the process, although some circuit configurations were better than others. When we hit the other end of the process, the speakers, we ran into another electromechanical component, and things got dicey again.
Speaker design in the era was something of an art; the designers worked without the benefit of either computer simulation or digital processing at the speaker. Since the frequency range of any speaker component is limited by its size and physical configuration, it’s usually necessary to build a crossover network of some kind to feed different portions of the frequency spectrum to different components. Between the limitations of passive crossover networks and the various configurations of the speaker “box” (a part of the sound generation process), speakers of the era ranged from good to hopeless.
Most were dreadfully inefficient too; in parallel with the “muscle cars” of the era, there was a power race in amplification to get the sound levels Boomer rockers and others wanted out of the things, and to avoid “clipping” which was yet another source of distortion. This was especially true of the “bookshelf” speakers of the era, most of which were stuffed with Scott’s acoustical foam to kill as much of the effect of the box as possible. Others attempted to redirect the backward waves forward. This improved efficiency but, if not done properly (and generally it wasn’t) the result was a muddy sound due to phase shifting. The most successful speakers of the “reflex” kind were the Arkansas produced Klipsch speakers, although these corner-standing behemoths were not practical for most people to have.
Others decided the best way to get to audio victory was to pitch the conical coil speakers and go to a “flat panel” configuration. This involved putting a membrane between two biasing plates, the biasing being either electrostatic or electromagnetic. The UK made Quad ESL’s were for many years “the deal”, and they, backed up by Quad’s amplification system (first tube then transistor), could match their company’s slogan of “the closest approach to the original sound”. On a smaller scale the Wharfedale Isodynamic headphones did the electromagnetic thing; the biggest advantage of these was that one could dispense with the externally powered plates by using permanent magnets. Today flat panel speakers are common, a testament to the vision of Quad’s Peter Walker.
And that brings us to Bose…although 1970’s audiophiles fought speaker wars with emotion, and many swore by them, Bose speakers of the era never struck me as particularly accurate reproducers of sound. Like many speaker manufacturers of the era, they produced a full line of them, and I always felt that the small, (relatively) cheap bookshelf speakers were the best of the bunch! The less you paid Bose, the better a product you got!
What I suspect is that Dr. Bose was attempting to produce something that was beyond the design capabilities of the era, which may explain the broader success of his later products. (He was also a vociferous defender of what he produced, which intimidated critics).
Personally I moved on to computers as a “hobby” interest, although I suspect that many reading this blog wished I has stuck with the audio equipment.