NewcastleFalcon wrote:Now this is another decca series which I just about recall
I was curious about this Phase 4 Stereo so I looked it up...
Wikipedia article
I well remember the 'gimmick' demo records of ordinary stereo that made sounds move around the room... Some early mono to stereo remixes of classic tracks also over-emphasised the stereo effect with vocals in one channel and instruments in the other...
And I recall well quadraphonic in the 70s. One of the engineers at the TV workshop has a quadraphonic Radiomobile 8-track in his Zephyr 6.... He had a few prog rock quadraphonic cartridges, one being the Floyd's Dark Side Of The Moon
It was magical in quadraphonic...
I was keen then to get into it myself but my meagre pocket money never stretched to building a 4 channel amp and speakers, buying a suitable cartridge for my Garrard SP25 record deck and buying the necessary records to play so it forever remained a dream.
Interestingly, the wiki article mentions the Hafler Circuit... These could make a kind of quadraphonic sound from a stereo source and indeed a kind of very poor stereo from a mono source...