What is the best premp for Atma-Sphere MA-1 3.3 amp?

 @select-hifi    

A number of people indicated that A-S MA-1 goes well with 545s. Compared to Nords or other SS amps, you don't find MA-1s lacks the dynamic/punch sound of SS?

Just to quickly chime in and please note I am a dealer for A-S. Yes the MP-1 is clearly better than the MP-3 but it's also substantially more $$$ not that $$$ has anything to do with SQ but in this case it does. The 3.3 vs 3.1 or 3.2 is also better in the MP-3. Personally I did prefer the MP-1 3.2 line section vs the MP-1 3.3 line section but the phono section in the MP-1 3.3 is again clearly better/quieter. These are my own subjective views. 
I can also say I bought SL 545's and as much as I really wanted to like them (I LOVE their bigger speakers) I just could not get them to sing. Roger West did take them back after almost 4 months but still it was a $$$ learning experience. 

(Dealer disclaimer)

sksos

Is it possible that your room was too big for SL 545?  What is your room size?

What did you use do drive SL 545? A-S MA-1?

Room size is approx 16' x 26' with 10' ceilings. M-60's with Zero Autoformers (not enough power) Bricasti amplifiers as well as Merrill Audio Veritas and even tried the new Merrill Element 118's. There were other amps as well and again just could not get the SL 545's to sing.

(Dealer disclaimer) 

So, do you think 545 was just too small for your room?  Not because of weak amp?