🚀 go-pugleaf

In article <3463@polari.UUCP> mzenier@polari.UUCP (Mark Zenier) writes:
>Some of the first ones used 1 D/A and sample and holds. The 
>BBC wanted to broadcast monophonic off of some CD's.  With
>the half sample time delay, it made the signal sound terrible.


WHAT???  I saw the few posts about the time delay alledgedly IMPOSED
by using a single D/A.  A little thought reveals that using 4 sample
and holds and 1 D/A removes the time delay completely, and S/H's are
cheaper than D/A's.  

S/H1 locks the D/A output for the left channel as it comes off the
CD, S/H2 does the same for the right channel.  S/H's 3 and 4 grab
the values of S/H 1 and 2 just before the next set of values gets
locked in, resulting in an output completely in phase.

Joe Touch
PhD Candidate
Dept of Computer and Information Science
University of Pennsylvania

Time	1	2	3	4

CD	L1  R1  L2  R2  L3  R3  L4  R4 

D/A	L1  R1  L2  R2  L3  R3  L4  R4 

S/H 1	L1------L2------L3------L4-----

S/H 2       R1------R2------R3------R4------

S/H 3	       L1------L2------L3------L4------

S/H 4	       R1------R2------R3------R4------