Consumer stereo audio first appear in 1982 with the Marantz VR 200. It was not Betahi-fi, which came out the following year, but used the normal (monaural) audio head split into two channels. The ACE assembly (where normal audio is recorded) was different and had dual magnetic pickups in place of the single monaural. Performance was good but the slow speed of video recording made for marginal performance compared to vinyl records (LPs). Noise reduction was used to enhance the sound but it still didn't match the fidelity of LP recordings. Plus the tape had to be very high quality, super flat and the speed had to be very uniform. When Betahi-fi came along dual stereo recording by using the stationary ACE assembly all but disappeared. Some high-end and specialty models did employ linear stereo but it was there to compliment the Betahi-fi audio. It was recorded along with the Betahi-fi FM recording that is inserted into the video signal. This added capability made for some interesting recording options. For instance if you wanted to record using just the linear stereo you could do this by simply turning off the Betahi-fi. Only the linear tracks would record and be played back. You could also record in Betahi-fi and then add two audio tracks later to the linear audio. These inserts could be a SAP, foreign language or commentary. (You cannot edit or add to the Betahi-fi stereo because it is placed inside the video signal.) Having several ways to record audio expanded the options enough that Sony included it in their professional GCS-50, SLO-420 and others. It also was featured in a number of Japanese models including their versions of our SL-HF2100 (their SL-2100) and our SL-HF1000 (their SL-HF3000). ©Misterßetamax go to homepage