CD-4 (Compatible Discrete 4) was also known as Quadradisc
It was as a discrete four-channel quadraphonic system for vinyl records.
The CD-4 system was created by JVC and RCA in 1971 and introduced to the market in May 1972, many albums were released for this format., usually clearly marked as such on the front cover of the album.
However to hear the records in quad sound, a special demodulator was required in the user's sound equipment.
To maintain the full effect of the quad sound, some periodic checks and "fine tuning" were required, this record was intended to be used as part of this "fine tuning" of the quad sound system.
Special CD-4 test record from Matsushita Electric Industrial Co. Ltd (Japan)
More well known as National Panasonic
National Panasonic CD-4 Test Record
Matsushita Electric Industrial
Cat# SPR 113-1
Released 1970's
Play at 45rpm
This was a test record kept as a service spare in our previous pro audio business, but I don't think we ever used it
Cover is in excellent condition, no edge wear, no tears, no seam splits, no writing on the cover
Instructions on how to use this record are clearly printed on the rear in a step by step fashion
Original special inner sleeve is supplied
Vinyl is excellent, as far as I can remember this record was never used and the visual inspection of the record indicates this
New outer protective sleeve is supplied
This test record primarily deals with Right and Left channel separation adjustments and Balance
Tracks:
Side A
Introduction - begins with some music, then spoken word instructions by a "Japanese American" voice talent
Separation of Left Channels
Separation of Right Channels
Sound Volume Balance
Side B
CD-4 format 4 Channel source material
Love Theme from the movie, The Godfather (orchestral)
