boji
Well-known member
Some formats give OPA's their own 0v rail as distinct from audio reference (Pin #3 / Pin #5 in 500 series).Ian: "At Neve, we used a brass bus bar for B- (=AGND) which was tapped at regular intervals along its length. "
Other designs have a single reference for OPA and audio, sometimes even when there's led's and mute fets sharing the same power source.
Further still, some discrete OPA's don't have an 0v pin or I've read they aren't always needed.
Are these single / dual references arbitrary, or Is it that some designers put more trust in decoupling/filtering caps than others?
I ask because in my power distribution, I've added a seperate bus bar for OPA power reference as distinct from signal ref (tied together much later), and would like to know if there's any advantage to doing it this way. Either method would have decoupling and smoothing caps everywhere.
Thanks in advance for your opinions/comments,
-Boji