slightly ot: DAT clock deviation

[Martin Czech]

Another way would be to sacrifice one stereo channel for the (reference)
signal, ie. the pseudo random and to have only the other one for
measurement.  This is described in "Simulation of Romm Acoustic Using
Head Related Transfer Functions", Gerry Beauregard et al. Dartmouth
College, 1991.

They claimed that still they weren't able to correlate repeatet
recordings. I can not understand why, cause the reference is always at
once recorded on the other channel...

But they also describe that they had lots of trouble because of over
or near Nyquist frequency components of the pseudo random, that upset
the ADC.  This is a very good hint, I have to test my DAT what happens
for -say- 100kHz sine input etc.

If this doesn't work, I must go linear:

shift register -> filter-> linear amp->speaker


It is possible, that Beauregard tryed to determine the relative position
of the pseudo sequence on the tape instead of correlating each single
recording with it's own reference channel which was recorded in the same
take. Then I'd understand their problems.

m.c.