SET the best?

My speakers are 97 db and 16 ohms. I find that 30 wpc is not enough- its much easier to play the system if I have 60 watts. But the amps I use are designed to not generate any loudness cues to the human ear (unlike SETs, which rely on enhancing the 5th and 7th harmonics to get the 'dynamic' sound that SETs are known for), so I use the power without the system sounding loud. My room is 17'x 22' and is moderately lively with lots of diffusion. I do like to listen at higher levels, often reaching 100-105 db, but the system is relaxed at those levels and lacks any hint of being 'loud'.

I put 'dynamic' in quotes here and above because IME, many audiophiles when using that word are often referring to distortion of the 5th and 7th harmonics instead of actual dynamics. The way this works in an SET is the 5th and 7th harmonics don't show up until you really push the amp, which is usually on transients. So the loudness cues exist on the transients, but not in between. This is why SETs are well-known for being so 'dynamic' in a way that is out of proportion to their power. IOW its a psycho-acoustic effect.

This is why so many SET users play their systems at relatively low levels- the loudness cues created by distortion prevent them from wanting to turn it up. But if the system is designed to avoid these harmonics and has the ability to play louder, it will be very natural to do so.

Hi Mike, I don't think any of us can answer your question, we can only offer clues from our own experiences that may help you find YOUR answer. Here is a summary of my experiences.

I've been in this hobby over 40 years and have owned many different types of speaker. I finally settled on a design that pleased me for the past 19 years, until I changed those this past summer. My long-term speakers were a large, floor standing design that offered a full range response with very good soundstaging and tonal accuracy. They were rated at 90 dB and were touted to be "easy" to drive. But they were also rated at 4 ohms and their load dipped below 3 ohms at two point on the spectrum. Therefore, they were difficult to drive and I tried many different amps, SS and tube, medium and high power, before settling on 800 wpc mono blocs.

Within the last few years, three of my friends changed their systems to speakers of 97 dB or higher. As we frequently visit one another for listening sessions, I came to two realizations. First, high quality efficient speakers seem to offer more sense of "aliveness" than less efficient speakers, all else being equal (and here I would agree with those who suggest at least 97 dB to truly be considered efficient). And second, even with efficient speakers, amp matching is important to insure adequate power -- one of these friends progressed through a series of amps from about 4 wpc SET to about 16 wpc PPT and each power increase resulted in a more musical presentation.

Influenced by these listening experiences I sold my long term speakers and bought a pair of Cain & Cain BENs, rated at 97-98 dB. I'm still experimenting with amps but I've reinforced the idea that 15 to 20 wpc are needed to simulate live music experiences, even with such efficient speakers.

The other factor of course, and as others have mentioned, is the size and acoustics of your listening room, the type of music you listen to, and your preferred listening levels.

But my summary conclusion is that SS/tube/SET/PP/OTL etc. is not the critical factor. Finding speakers that suit you best, then searching out the best matching amp for THOSE speakers will be your key. Good luck and have fun along the way.

Thanks guys, a lot of great information here. I missed out on the speakers I was looking at, but I may try to grab a new pair of demos. I have been reading non stop, researching many different amps. I think I should change the speakers first before I get hung up on the amplification like many of you have recommended. I am in the process of changing my current amp for one that will work with both my current speakers and the ones I plan to upgrade too, then I can play with the super low watt SET's in the future.

Thanks again,

Breuninger, it was really cool to read your thoughts on this subject. I know you come from a place of experience and I've slowly been coming around to share your opinion.

Hearing you say that stuff makes me feel like less of a traitor for coming back to push-pull and solid-state amps on speakers that dip below 6 ohms and are less than 88db sensitive. Haha.

Atmasphere you said {This power limitation is one reason why I don't use SETs. The bigger you make them, the less bandwidth and detail} Please explain if you would for this doesnt seem to make sence, maybe its just wordered wrong. Maybe Im not getting your point. But power rating in SET doesnt have anything at all to do with bandwidth its the SETs design. Mostly the transformers used. I have owned SETs with limited bandwidth but if of proper build this isnt a universal SET problem. Now if you dont have power your loudspeaker requires thats a system matching error and not the fault of the SET amp but of owners system choice.