Recommendation for a highly resolving amp


I have Don Sachs 2 tube preamp driving Pass Labs X350.5 driving Sound Lab M545 ESL speakers. I like the sound very much, but when I went to hear my friend’s Spectral system (driving Quad2912 ESL) I realized my system can benefit from having a higher resolution amp. Spectral amps need all Spectral preamp/cabling, which would be quite expensive. What would you recommend?
128x128chungjh
it all starts in the front end but if its good next are the amps
my amp and preamp are Aesthetix very resolving

Enjoy the Music 
Tom
Can you explain exactly what 'resolving' is or means?
Not intended as bait; I really do not know what this means.
I have tried fiber optic and other top 6SN7 tubes. Not big difference. By resolving, I mean high resolution, clarity, detail.

What do people think about the Bryston cube series? Specs are similar to Spectral amps.
You have a very nice system so it's hard to say where your issue is. However I would try a Sanders Magtech amp if you are looking for a new amp, they are designed for electrostatic loudspeakers and do that job really well.