Based on much of what I’ve read, and some direct experience, having a tube in the circuit [amp or pre-amp] is often a sonic benefit. Early on in my audio adventures, I teamed a Dynaco pre with a B & K solid state amp. I once had a classdaudio sds amp [class d] fed by an Eastern Electric tube pre and I thought the combo was excellent.
Right now I’m considering a tube pre with the class d Crown amps Tom and Dave have recently touted based on their personal listening experience. The "issue" there is why bother with ANY active pre-amp when a digital source does NOT require the gain stage in a pre-amp? If anything the pre-amp is used as a volume control to attenuate the signal.
Well, very recently I spoke to a well respected audio designer and asked him about this matter.
He suggested that the best sound from a digitally based system is to run the signal from the DAC directly to a tube pre-amp [BYPASSING the dac’s inboard analog output gain stage]. His point is that a great tube pre could provide the “gain” needed in the digital realm with superior fidelity than the DAC’s inboard analog gain stage. I think his concept has a lot of merit. He achieved it with an NAD cd player and loved the result. I’m actually wondering if this can be achieved with most DACs and would like to try it. I HAD been thinking a digital signal “naturally” provides the 2 volt output so it does not REQUIRE any gain stage [ala a pre-amp], but, in fact, there is gain coming from the DAC itself. Food for thought. I’d welcome some feedback on this concept. Maybe, this deserves its own thread as I don't intend to distract from the main question here.
Good luck in your quest.
