Preamp for NADC370,please

Simon: Did you ever replace/upgrade the jumpers on the 370? If not, then I would try this first (as it is a weak link). Commercial reviews of the X-Pre state that it really needs the addition of the MF X-PSU to perform well. This has been said of all the X-gear that uses the little stock wall wart, for a power supply, and makes sense. Also what tubes are you running in the CD player? This could be another possible upgrade? Based on your goals of "softer HF's and fuller bass", certain 6dj8/6922/7308 type tubes can supply this sound and some not. Smooth HF's suggests tubes from the Amperex/Philips/Mullard group with Amperex white label USA's being my favorite all around tube (6922 or 7308 - both are good).

Thanks Dekay for your info. BTW,I have replaced the jumper of my NADC370 with TruthLink IC(same IC I used for CDP connection, only half-shorter,0.5 m).Do you think replacing the JAN Philips 6922 stock tubes of the CDP with Amperex 7308 would do it(softer highs,heavier bass)? It seemed that there is no sense of using MF-X PRE without pairing it with the X-PSU is'nt it ? The ads of Parasound HP850 preamp stated that it is supplied with 1900 uf cap?? so that it would deliver extensive punchy bass,I wonder if this is true?? Perhaps you and any one might comment on this and thanks
Simon

After spending some more time listening to the preamp section of the NAD C350 into the AMC tube amp, I am starting to think the NAD's preamp section is a bit rough and electronic sounding. I am either going to get some mellow interconnects (I am using revealing ones at the moment) or another preamp. While a good tube preamp will probably give you the best sound, I used to own a Classe DR-4 which was a very rich sounding piece, better than at least one hybrid tube preamp (Audio Note Zero) that I compared it to and certainly better than the NAD. A used DR-4 should be in your price range and will likely be better than the Parasound or the X-Cans.