Have you heard the Aria amps by Mike Elliott?

Like PhilD, I got my SA-100s totally rebuilt (Premium Gold) with Silver Audio internal wiring and 15-amp IEC receptacle. They are very close to Aria by the information posted on Alta Vista Audio web site. The sound is very netural and not too tuby. It is very similar to Atma Shpere OTL sound but faster. The tube selection is critical, I have tried VT-231 (Sylvania, Ken-Rad and RCA), 5692 (RCA, Sylvania, Tung-Sol and Raytheon), 6SN7-GTY (Mullard and Brimar), 6SN7-GT, 6SN7-GTA, 6SN7-GTB, 6SN7-WGTA, 6SN7-WGT and 6SN7-W. The only thing I havn't tried is the ECC32/CV181 as fas as I know. You have to experiment to see which tube is the better fit for your personal taste. The only thing I am still trying is to enhence its bass authority. Not they don't provide enough bass, I just want to a little bit more.

The associated equipment is listed below for your reference:

Source - BAT VK-D5 (with Amperex 7308)
Line Stage - Counterpoint SA-11 (with Tung-SOl 6SN7-GTB)
Power Amplifier - Counterpoint NP-100 monoblocks (with RCA smoked envelope VT-231)
Speaker - Theil CS 3.6 / Silverline Auido Sonata MK I
Speaker Cable - Ensemble Megaflux / Silver Audio Symphony 48
Interconnect - Silver Audio Appassionatta
Power Condictioner - Chang LightSpeed 9600 MK II
MUSIC - Classical

As you can see, I havn't decided whcih speaker to use yet.

PhilD,
If you really enjoy Counterpoint SA-5000, you might consider to try the SA-11. Just a suggestion.

Happy Listening!

Otto