Possibly. I had issues when I did this. I was using a Singlepower Supra++ (old school chassis as well) -> Musical Fidelity A300 power amp (whose gain is insanely high) -> Dynaudio Special 25's (full-range speakers), and I got this bass clicking -- had something to do with being full range drivers; sounded like tubes expanding when warming up. It wouldn't do it on Hirsch's bookshelves, but it did do it when we tried to use it on a subwoofer of his. Hirsch contacted Mikhail about this, and determined the "problem", part of which was that it wasn't intended to be used as a preamp. Mine is an early model, as is yours, so yours could have the same problem. There is a fix for it. It has something to do with the power supply. I would contact Mikhail about it -- he should know if yours was before or after this or not. It's not a fault of the amp's, I should emphasize -- I believe the ones with a preamp out do not have this problem at all. It might just be a DC filter on the output, but I honestly don't remember. I never "fixed" it on mine, as I got rid of the amp (money crunch) before I had a chance to investigate it.