Hello to all,
     Perhaps Mr. James Tanner might be able to address this issue.  I would like to run two preamps into my 7B-STs: a Bryston BP-25 into the balanced inputs (as I am doing at present), and an Audio Research SP-9 hybrid tube preamp into the single ended inputs (not yet installed).  I assume that I can simply toggle the preamp by using the "unbal - bal" input selector switch on the back panel of the 7B whenever I want to change from the BP-25 to the SP-9 (all powered off, of course).  Can anyone see any problems with this setup?  I want to try a tube preamp as the front end for analog LP playback.  Another recent post mentioned possilbe problems with DC output from tube preamps running into wideband power amplifiers like the 7B-ST.  Could this be checked with a VOM?
Thanks in advance,
Steve W.