Atmosphere listed some very good choices, and there are even more available if you are into DIY.
I have owned Rogue preamp and amps. I have always found them to be a clean, clear, non-tubey sounding equipment. Based on this I think I understand what you are looking for.
Changing speaker posts, by-passing is even better, will possibly allow more details to come through but won't do anything for speaker colorations.
I'm not sure I would agree that there are speaker made for SET. There are certainly very efficient speakers, but that just helps SET work with them. The coloration that you have heard with such speakers could very well be coming from the SET. Like speakers, some SET are less colored than others.
Also, there is nothing wrong with running very efficient speakers on 150 watts/ch. I have added a second 50 watt PP amp to my horns and the improvement in bass control, as well as enhanced separation, is amazing.
I have owned Rogue preamp and amps. I have always found them to be a clean, clear, non-tubey sounding equipment. Based on this I think I understand what you are looking for.
Changing speaker posts, by-passing is even better, will possibly allow more details to come through but won't do anything for speaker colorations.
I'm not sure I would agree that there are speaker made for SET. There are certainly very efficient speakers, but that just helps SET work with them. The coloration that you have heard with such speakers could very well be coming from the SET. Like speakers, some SET are less colored than others.
Also, there is nothing wrong with running very efficient speakers on 150 watts/ch. I have added a second 50 watt PP amp to my horns and the improvement in bass control, as well as enhanced separation, is amazing.