Last month I looked at a turntable design from Garrard that if it had taken off might have meant no need for CDs at all, allowing as it did the possibility of up to 5 hours playing from an LP. Alas its lifetime was little more than my interest in MiniDiscs. This time round I conclude my look at turntables and arms with other ideas that could have changed the fortunes of vinyl before its revival (or should that be revinyl) in the 21st Century.

Whilst the Garrard invention meant an increase in playing time, another invention from across the pond would effectively lead to a halving of the playing time. This idea, and published in the US High Fidelity Magazine in 1956, was for a clever lateral playing tonearm developed by Truline (The Reproducer Arm) that contained two cartridges that kept a finite distance apart. This allowed the Cook Livingston method of stereo whereby the two legs of stereo were kept as two distinct tracks side by side on one side of an LP. This was to be confusingly known as Binaural stereo, not to be confused with dummy-head-stereo. Emory Cook believed the stereophonic record as we know it today, which was invented in 1933 by EMI’s Alan Blumlein, was not good enough.

Blumlein’s idea had each leg on the two sides of the record groove kept at an angle of 45 degrees to the vertical, and does mean that crosstalk of information will find itself infecting the other leg. Blumlein joined EMI’s central Research Laboratories at Hayes, Middlesex, in 1931 when Columbia and The Gramophone Company merged in the same year. Over his lifetime he was a prolific inventor, responsible for much of the stereo we take for granted today. After a night at the cinema with his wife he was frustrated that the sound from a character on screen never seemed to appear where the image on the screen was. He looked at how to re-create the features of the sound-field that we pick up from our ears by creating the coincident-pair microphone system (also called Blumlein pair), whereby two microphones were placed close to each other and toed out for left and right. Many audiophile sound engineers use this approach for un-processed un-complicated true-stereo recordings. Incidentally the very first stereo microphone system was actually by mistake at the great Electrical Exhibition in Paris in 1881 by a Clement Ader, who was demonstrating an early telephone system similar to what we now call the spaced-microphone stereo technique. No one took an interest in this idea then, so he went on to invent the inflatable bicycle tyre and then started playing with aeroplanes, calling his first plane ‘A Vion. Of course these two words were later joined together to become the generic name used in the French language.

Blumlein’s next task was to look at how to create stereo on a gramophone yet still remain compatible with the existing mono records and record cartridges. His idea involved creating a complex cut on the gramophone record with two imprints at 45 degrees to the vertical on either wall of the groove that could be read simultaneously to playback the new stereo (Binaural) audio. On the 14th of December 1933 the first wax disc was cut in a test recording of stereo sound at the auditorium of the EMI site, a number of years before the invention of PVC and the 33 1/3rpm LPs. Another stereo experiment from the late 1920s involved playing a record vertically on a special record deck with two arms, one for either side of the disc, with one for left and one for right. Alas, this idea didn’t catch on. With only Blumlein’s idea being taken seriously for stereo replay, Emory Cook considered the invention not developed enough to be effective in terms of stereo separation – indeed one of the arguments highlighted in the promotion of the CD – and that the only successful approach to having two distinct legs was literally by having two separate grooves. Because it came a bit too late and wasn’t compatible with conventional mono or stereo LPs the idea died pretty quickly. Also, because of the lower fidelity and high frequency distortion of the inner groove due to its effectively slower speed, he used two lateral grooves with a 500 Hz crossover in the inner track to try and compensate. It didn’t work. Also, with the duration of the “long” playing record now being similar to the shellac 78s from before,  its improved audio wouldn’t make up for the reduction in playing time.  Stereo separation has of course been a major issue in vinyl ever since, and cartridge tilt and azimuth are central to providing the best crosstalk from your cartridge. Some manufacturers such as Jolida and their Foz XT-R Crosstalk Reduction Device aim to improve image focus and soundstaging electronically from any cartridge, though this idea is limited to 40dB separation.

My final look at turntables that could have changed the world was my favourite ADC Accutrac 4000, which was a very able direct-drive turntable with automatic track selection and a computerized memory bank. The American company was actually owned by BSR (The Birmingham Sound Recorders) who were Garrard’s main competitor in their heir day. This turntable could play tracks in any order from the comfort of your armchair, something we now take for granted with other forms of replay. The Accutrac wasn’t however the first ever “automated” turntable. That one was by Toshiba back in the 70’s, but it is this unit that will always be remembered by me not least because of the very 21st century silver “bulb” receiver for the remote control handset.

I have looked over the last two months at forward thinking ideas that could have made a big difference to vinyl replay in terms of quality and playback-duration. It seems weird that having been accustomed over the last thirty years to mass-storage, long playing times and ease of playing from MP3,WAV,HD Audio and CD, audiophiles are now working their way back in droves to playing a 24 minute vinyl with limited crosstalk and scratches. Perhaps the Cassette tape will be the next to return. Now, where is my Nakamichi Dragon…?

Janine Elliot

Read more Retro Bites with Janine Elliot


You must be logged in to leave a reply.