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SET 45 Amp Driving Dynamic Speakers

I have an Antique Sound Labs Tulip SET amp running Emission Labs mesh plate 45s, driving Audio Note AN E speakers. It will play WAY louder than I want to listen, and the dynamics are amazing with all types of music.

Why do I keep reading that 45s (and other low power triodes) are only appropriate for horns, or other super efficient speakers? I think a real disservice has been done to the audiophile community by the propagation of this idea. IMO, anyone who prefers to listen to music at sane levels can enjoy the many benefits of a low power SET amp with carefully chosen dynamic speakers.

Anyone else feel this way/have similar experience?
tommylion
lewinskih01
912 posts
 

Hello Al.

Thanks for the excellent and thoughtful reply. I've gone through it several times in the last couple of days.

You made it very clear so I can work through the tradeoffs. Maybe running the amp up to 50% si not as offensive? Something to try and learn.

I think most of my music is going to be rather compressed. Of course I have some good recordings, including Telarc's Firebird you mentioned, but the majority of my listening is going to happen with lesser quality recordings. Let alone having 3 kids into teenagehood and wanting to share some listening time with them, with their music ;-)

FWIW, I'm working on the midrange driver. It's a horn-loaded cone, so efficiency is yet another tradeoff in the design. I believe 100dB/W is about a floor, and probably a cieling around 106dB/W. Hopefully I can get it to 103-104dB/W and then things start to look significantly better. Or I'll have to settle for a 2A3 or higher power amp.


Glad to see a healthy thread develop on SETs. I'm hoping that eventually more people will be open to try what well-implemented DSP can do for a system (emphasis on "well-implemented"), just like Charles was open to experience well-implemented digital. Not saying it will be best for everybody, but I find it a pity people follow so many preconceived notions in audio and preclude themselves from trying new things. OK, time to get off my soap box :-)

charles1dad's avatar
charles1dad
10,250 posts
 
Lewinskih01,
You have the right attitude and I wish you well. Sometimes you have to ignore well meaning warnings based on preconceived notions. When I became interested in SET amplifiers the warnings were, limited music genre, pleasant but very colored midrange, very little  bass or high frequency information. All were completely wrong and in hindsight total nonsense. The past 7 years with my SET 300b based system  has provided the most  vibrant,open,transparent, organic and emotional involvement I’ve ever experienced. I wish you the best of success moving forward with your project.
Charles,
atmasphere's avatar
atmasphere
12,171 posts
 
I've often been amused by the comments in Stereophile about how an SET can measure so poorly and yet sound so good- and further that no-one seems to know why. I have to assume that they did not ask any designers when that comment was made.

IMO low distortion is pretty important, and as long as you don't push them hard SETs can have distortion lower than any solid state amp. And when you ask a little more power, you get the 2nd harmonic which is a lot less offensive to the ear (even in large quantities) than the higher ordered harmonics of solid state! So its no surprise why SETs have a following.
mapman's avatar
mapman
22,969 posts
 
"Sometimes you have to ignore well meaning warnings based on preconceived notions. "

How someone thinks something sounds good or bad is a notion.

Technical facts are facts however, not notions. You can choose to ignore them but chances are higher you may regret it later if you do.


That’s not to say technical facts tell the whole story either. They do not. But they do set the foundation for how the story is most likely to end.

tommylion OP
874 posts
 
I’ve only heard SETs with horns at an audio show. I recall an Art Audio amp with PX25s driving Avantgarde speakers (Duos?) that sounded REALLY good. I don’t doubt that 45s et al can sound even better with horns.

What I am saying is that those who don’t want horns (for space, budget, WAF, or other reasons) can still get a lot of the virtues of SETs with well matched, higher efficiency, dynamics. That was not at all the impression I got before trying it for myself. I know there are always trade offs, but, in my case, I have a hard time perceiving any significant ones.

Horns are not an option for me, at least right now. Maybe there’s an amp out there that can give me the the "magic" of my 45s AND greater dynamic headroom, with my current speakers. I’m not chasing after it, though.
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