Ultralinear vs. Triode vs. SET

I can't qualify my preferences like Atmasphere, but like many, I find the limitations of SET's too restricting. My adventures in audio began with solid state, but as soon as I realized that tube amplification was the common thread shared by the systems I liked, I've been devotee, and spent time with several examples of your subject designs. All choices involve some compromise, which then boils down to your personal musical values. The best compromise, for me, has been a well executed 300b push-pull design of moderate power. My tastes in music are pretty wide ranging and this design has allowed me to enjoy the entire range without extreme limitations being placed on my choice of speakers.

I currently own an Atma-sphere OTL (S30), 4 SET amps (45,2A3,300B,GM70), a SEP amp (single ended pentode using 6CL6 tubes), a reburbed Dynaco ST-70 and a Class D amp. I have owned a myriad of other SS, PP and SET amps over the years.

With appropriate speakers, Single ended and OTL topologies bring me far closer to the music than any other type of amplification. The clarity and presence of these type of amps can be stunning. I'll leave the technical explanations to more qualified folks like Atmasphere. To my ears, the distinction between good SE/OTL and other amps is not subtle. It's readily noticeable.

However, saying that, there are a few important considerations when using these amps. First, you must match your speakers accordingly. For the most part, SET's will not perform optimally with inefficient speakers. If you love large planars and Electrostatics, then you are probably going to need to look elsewhere. Also, your listening tastes come into play. A 45 or 2A3 SET is wonderful with intimate vocals, small scale accoustics and jazz. Realistically, not enough muscle for Bruckner or Mahler symphonies. If you love large scale orchestral music, you probably want to look for a high powered SET (211,845,GM70) or OTL's.

If your speakers match well with either SET or OTL, I really think you owe it to yourself to investigate these amps. It can be a major ear opener.

Droz,
As predictable many opinions and experiences expressed here, as each type of amp design has some level of compromise(SET,PP,OTL,etc.) The 300b PP route is ok but won`t offer anymore speaker flexibility than say a 845 or 211 tube used single ended. There are`nt extreme limitations of speaker choices either( even if you choose a 300b SET). With a PP 300b you will gain power, but now you`ve introduce phase splitters to the circuit. The SET approach will generally sound purer and even more natural(very simpler circuits tend to sound more natural) Since the original post was an inquiry of SET AMPS i sincerely hope you have the chance to hear them in a well thought out system and judge with your own ears. Just for the record I can play any type of music I want with my 8 watt Coincident Frankenstein. Don`t think you have to limit your music selection at all.
Best Wishes

For my taste, a speaker well matched with an OTL is the very best type of amplification overall, especially if you include compatability with a broader range of speakers than is possible with most SETs; and much better frequency extension with very resolved midrange. If you are intrigued with SET, a good time to also consider OTL (Atma-sphere, Joule, Transcendent, and soon Music Reference - there are others).

Charles1dad made the solid statement that you would get many "opinions and experiences expressed here" and then expressed his. As I read the original post, it is not an inquiry exclusive to SET amps but a comparison between SET and other designs. While I guess the word extreme is subjective, we disagree that SET's, in general, aren't much more demanding and restricting of the speakers they're matched with.