I agree with Mrtennis. There are many great solid state preamps along with tube amps that will do well with the Wadia 581i SE. To name a few solid state preamps that I have enjoyed in the past were (Accuphase C-2800,MBL 6010D ref.,Spectral DMC-20 ref.,) tubes: (First Sound Paramount Mk II SE,VTL 6.5 sig.,CJ Art series 2, VAC Renaissance Mk II sig.). The reason I chose the Lamm LL2 Deluxe because of its price range, and it perform the best for its resolution (1.5hz-400khz), extreme transparency (neutral) when using my Stax 4070 cans/SRM-007tII driver. By using the Stax system and having a very good source, I was able to be very critique on the audio gear. Good Luck!