Johny B Good wrote:

I was going to mention the effects of phase shift on the harmonics of
a 500Hz squarewave played back from analogue magnetic tape where,
despite the oscilloscope display showing it looking nothing like a
square wave, it still sounds just like the original squarewave.


** That is not true of the vast majority tape machines which are well capable of reproducing a good square wave at 500Hz.

True of any decent cassette deck or R to R and includes Roland tape echo machines as well.

My standard test for a Roland 201, 303 and 501 models involves recording a 500Hz square wave and I except to see a good looking result on the scope.

Sure you were not thinking of 50Hz?



Also
the trick, when dubbing copies from a master tape, of playing the
master and slave recorders in reverse to cancel the effect of the
phase shifts, largely restoring the waveshape back to a semblence of
'squareness'.

** Very hard tobeiev it worked or was in any way necessary.


I guess the phase shift sensitivity reference Trevor is thinking of
is in relation to stereo detection of the direction of sound sources
rather than the percieved quality of the sound by each individual ear.


** For certain.


.... Phil


--
J B Good