[net.audio] anti-aliasing harshness questionable

joe@cornell.UUCP (Joseph Bates) (05/13/85)

I recently posted an argument to the effect that frequency dependent
phase shifts should arise due to the manner in which many speakers are
constructed (independent tweeter and woofer).  If there is a correct
position for one's head (highs and lows properly in phase) then
slightly higher or lower positions should have highs arriving earlier
or later than lows, resulting (by definition) in a frequency dependent
phase shift.  I wanted someone to explain why this was benign, while
the freq dep phase shift due to steep anti-aliasing filters in some CD
players is often claimed to cause harshness.

Several people have commented on the effect, explaining why the phase
shift due to head position is not likely to be audible.  What I want to
know is why the phase shift from the anti-aliasing filters is different
from that arising due to head position.  There must be some audiophile
out there wwho can explain this, or does everyone agree that the filters
have no audible effect (due to frequency dependent phase shifts, at
least)?  Please someone, give this a shot!

joe   (joe@cornell.arpa)