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
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I am using the CODA #8 and CODA 07x preamp with my Thiel CS3.7. It is an very satisfying sound. IT has good detail, lots of power for my speakers, and non-fatiguing. I did hear some increased clarity and resolution when I recently heard the CODA 07x and CODA #16 amp. The plan is to trade in the #8 for the #16. But it is not a pressing concern and I will take my time to do so. The #8 is a very good amp and the #16 is a great amp.

I think the #8 was not as clear and detailed as the Benchmark AHB2. However, I do not feel many amps are of that caliber. When I heard the #16 I was thinking the #16 was like the AHB2 in clarity but way more powerful with a bit more warmth that the AHB2. If I did not own the AHB2 I would have thought the #8 had a lot of detail.

I also love my CODA #8 paired with my Benchmark LA4 preamp. The amps and preamps from these 2 companies (in any combination) really appeal to me.

BTW - I am currently listening to my Thiel CS3.7 in my small room with the AHB2 + Topping pre90 ($599 preamp). I think it sounds real good when I am not playing too loud (most of the time). However, that bottom end is really not there with the AHB2 and Thiel CS3.7. My CODA 07x is in for repairs so I am using this combo until the 07x gets back. The Topping pre90 does not work with the CODA #8.
@chungjh Is your friend familiar with your system, your room and your preferences, etc.? If yes, what is he advising?
My friend is a Spectral man, so he recommends a complete Spectral system. Along with all the MIT cables.