Paul Hodges <[email protected]> wrote: > --On 25 January 2012 20:04 +0000 Richard <[email protected]> wrote: >> But was BBC ever using either of the formats officially? > > And given that HJ was defined to include within its tolerance zones both H > and 45J, they could by definition have simply continued using existing H > equipment and labelling the results HJ.
Matrix H and HJ were only ever experimental. (The BBC was making official experiments.) "Richard" <[email protected]> wrote: ... > I've the feeling I've more chance of finding the Holy Grail than find the > truth behind the H/HJ story For an individual recording, it should be possible to determine the encoding by measurement (he said with total ignorance). Matrix H has a 48 degree phase angle between the two channels. As Paul points out, HJ was variable, coming as low as 30 degrees. So, if the measured phase discrepancy is close to 48 degrees then use a Matrix H decoder. If it is less than this then use a UHJ decoder. (If it is close to zero then there is no encoding, and it is plain stereo.) All you need now is to work out how to make the measurement. This step has been left as an exercise for the reader.:-) Regards, Martin -- Martin J Leese E-mail: martin.leese stanfordalumni.org Web: http://members.tripod.com/martin_leese/ _______________________________________________ Sursound mailing list [email protected] https://mail.music.vt.edu/mailman/listinfo/sursound
