07-26-15: Audioconnection
07-26-15: Tls49((( One thing to keep in mind is that the input impedance is somewhat low (25K ohms), so a tube preamp with a very high output impedance (above 2.5K ohms) will not mate well.)))
Not, its 100 K no problem for a Tube pre amp
JohnnyR
Sorry JohnnyR, the 100K is for the Belles 150A. I had the manual with my original Belles 150 and the specification listed was 25K. I used a few different preamps with the 150, and did have trouble with one tube preamp. That's why I remember the specification.
I'm thinking of getting one of the Dynaco PAS units and rebuilding it. I've seen a schematic on line for a SRPP preamp circuit with an output impedance of about 3K Ohms.
IMHO, that 3K will be too high to work well with the original 150. Most will say the difference should be at least 10X, and even more would be better.
