A good match preamp for B&K EX-442 Sonata amp?


I just picked the above amp hoping for a warmer sound than my HK 635 receiver. Any suggestions for a preamp will be greatly appreciated. Thanks
rollerotr
I just noticed that my Harman Kardon AVR 635 receiver has separate stereo preouts (multi-room) to power an external amp. So, besides trying to find a good fit for my just purchased B&K EX-442 Sonata amp, how well will the HK do as a preamp?
TIA for any responses.
How much money are you budgeting for the preamp? As for the Receiver, I've tried using a few different receivers as a preamps (Yamaha, Denon, Sony) and while the addition of an outboard amp was an improvement, the receivers really didn't perform wellas preamps, and it wasn't hard to find a standalone preamp that out performed them in a big way. This may not be true for your HK, and it's certainly worth trying it.
Do to finances, I figure to spend about $150-400. Since I bought a 20 year old amp, I'm not opposed to same for preamp. I am more concerned with matching the (hopefully) warmer quality of B&K Sonata. Eventually, I may end up back to tubes!