I recently acquired a second pair of the WPA 3.5 (to use in a tri-amped
setting) and am trying to figure out what the story with the second set
of amps might be.
Most of the ones I have seen have a serial number and the initials of the
assembler along with a date (month/year). For example, my first pair have
the following info:
Serial number: 417 L 417 R
Assembler / Date: SH 5/01
The second pair have the following markings:
Serial number: 042 R 042 L
Assembler / Date: SM ROHR
It would stand to reason that the second pair were number 42, whereas
the first were number 417. What stumps me is the possible meaning of
the "ROHR" (in place of a date).
I am also interested to know which output transformers were used. On
the second pair, they are a gold color, whereas on the first pair, they are
black. From what I have read, various OPTs were used by George over
the years: MagneQuest, Sowter, and O-Netics have all shown up in various
searches. I've seen DeYoung come up, as well.
I have asked the gentleman from whom I purchased the amps about this
andhis reply was "Over the years I have owned many of his amps, pre-amps
and phono pre-amps. The 3.5s that I sold to you were used by George as an
experiment to see what the gold transformers would be like versus
Magnequest. George preferred the gold transformers but they were too
costly--he would have had to charge more for his amps and he didn't want
to do that."
Any ideas on who might have made the "gold" transformers or to what the
"ROHR" designation might refer?
Any insights / leads would be appreciated!