tube preamp please, replacing counterpoint sa7

the rest of my system consists of antique sound labs mono blocks- the real small ones, ecl-82 driven at 7.5 watts each driving a pair of NHT super two's. i was using the NAD 705 as a preamp before the counterpoint and bass was no issue even with controls at flat, so i don't think my power amps or speakers are an issue. as a source I am using a rega planar two with a grado silver which i have also had for a while, the only variable is the preamp. the tube change sounds like a good first step because i love the sound and simplicity of the SA7 and would keep if i can improve the bass. its just too loose and undefined right now. it is also excessively noisy which hints me more at tube replacement.

Both before and after the tube replacement, you may want to play with speaker placement and lister position (if you haven't already).

Go for the best tubes you can buy from Andy. You won't be dissapointed. You might consider re-tubing your mono's next. Ask Andy for his advise. I got lower noise floor, holographic sound stage and improved bass extension right away. Everything improved from there over the next month until they were fully broke-in.

You were happy with the NAD 705, which makes me think that going back to the NAD is the solution, but perhaps there is a low frequency roll-off with the Counterpoint preamp that can be resolved. 

Hope after 15 years he solved the problem!