SET Tubes - Sonic Differences

They all sound different. I would stick with triodes: 300B, 45, 2A3, 845, etc. at least to start. What you are talking here is purity of sound, not huge amounts of power. Speaker sensitivity is critical. You want the highest number of decibels at 1 watt/ 1 meter. My experience has been that the sound achieved through simple but elegant Single Ended Triode power amps is so lovely, musical, fast, and somehow "right" that there is no going back. I would choose an amp that has a tube rectifier rather than solid state. If you want to listen to music playback that conveys the delicate sense of the real thing, that wonderful feeling of life and emotion in the music, then SET is the only way to go. The lower plate impedance tubes ( 300B, 2A3, etc. ) seem to my ears to garner first place in the "how do they sound" department.

I agree with the above. I've been playing with SET'S, push-pull etc for years, and unequivically the most real, beautiful music I've heard is on SET's in general, and the 2A3 tube in particular. Certain 2A3 tubes have the bass oomph of a 300B, and in the mids and highs the 2A3 outdistances the 300B by a wide margin. A simple yet elegant 2A3 based SET is magic. And a KR enterprise 2A3 tube, although expensive, delivers the low end goods in spades.( RCA NOS tubes are also great) The simpler the design and the better the output transformer the better. The music lives. A sensitive speaker is needed, hornloaded or otherwise. But the result can be musical magic. OPT-less amps are also wonderful, such as Atma-sphere, and the low ends are much better than the critics are warning. One of my amps is a very simple Fi 2A3 designed by Don Garber which I have modified with Tamura OPT's, and on the right, ie sensitive, speakers these things breathe life into the music. And don't let the low power of the tube fool you, the 3-5 Watts in a KR Enterprise 2A3 can drive the right speaker to ear shattering volumes without clipping, not that I recommend or practice this. Give it a try, SET's may just be your cup of tea. Have fun!