Hi Keith!
 It sounds like you did your grounding via the brute force method on
your board design. That works too, most of the time. Seperating chip
grounds from signal grounds can be a problem though in this situation.
Paying attention for ground loops can be done on a board level though.
Ah yes, Walter Jung is THE MAN as far as Op Amps go. I have learned much
from him. Some of the best information I ever recieved in AUDIO was from
Bill Dilley from Spectrasonics, Inc. I attended along with a small group
of similarly inclined individuals a seminar that he gave, where he
started off telling us that everything we knew was wrong and proceeded
step by step to prove it. Was only a couple of days, but what a couple
of days!!!! I haven't been the same since and this was many years ago
now. That and some seminars with Don Davis and Syn-Aud-Con.
Your idea of getting the transformer away from the box was probably your
biggest contribution to the low noise of your preamp along with your
care in grounding techniques.
 Bonnie *:>
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