Dumb question......why do you need a preamp?

Some integrated today are more than enough ,if that what you need. Many yrs ago Dan Modwright modified my Sony sacd player 9000 es with a very good volume control . I used it direct to amp.I like the sound better. Before I heard a Backert preamp ? I never care for preamp, Now I have 5 preamp 4 tubes , one solid state Krell Krc3.

My MSB Discrete DAC has a volume control and plenty of output. Almost 4v at 300 Ohms and close to 2v at 150 Ohms. I use predicted 150 Ohm 2v setting and without a preamp. I owned a Benchmark HP4 preamp and I found that the sound was better without it. So I sold it. The MSB has a high quality volume control and I only have a digital source. 

For me the pre amp is the hub of all the components.

Streamer & cd player to DAC. DAC to preamp, tt to preamp, one pre out to sub, 2nd pre out to main amp.

I use a old recapped Carver c4000. Attenuators for high & low HZ, balance, filters, an awesume sonic holograghy feature which enhances soundstage.

Even has a built in amp for time delay speakers. I dont use it anymore but it gave a nice concert hall effect or " opened up" a small room.

Added gain, drive, dynamics, energy and sound stage. 

I have a luxman L-507z integrated amp. I havent seen anyone put a tube pre-amp on it yet. Altho with cornwalls it might be interesting. 

@paqua123 - The Luxman integrateds really are something special.  Many manufacturers claim that their integrateds have their top of the line preamp circuits built in and who knows but in the case of the Luxmans I honestly believe it.   The difficult thing for me is that I'd actually like to go fully active, and trade from the Luxman integrated to Luxman pre, but the pre's are like 2x as expensive as the integrateds.