Axiom Home Page Forums General Discussion Technical Questions Using Low Power SET Amps - Questions Re: Clipping

I recently finished building my first DIY amplifier - the "Bugle" designed by Gordon Rankin. It's a single-ended triode amp that uses type 45 ouput tubes and produces 2.5 watts/ch. I've had some comments on another board (Audio Asylum) that I should really consider getting some high efficiency speakers to get the most out of this. I've been using a variety of speakers, both vintage and modern, including original Large Advents, Advent/1's, stacked Advents, Axiom M3ti, Michaura M-55, Michaura M-66) I've been amazed at how loud it plays (and especially how it SOUNDS!) but I'm concerned about the possibility of damaging speakers due to clipping. I'm not hearing any distortion or compression at the levels I listen at (not extremely loud) but I've had comments that it might be clipping more than I know. If I can't hear anything that sounds bad am I OK or is it possible to damage the speakers even though the amp sounds very clean and dynamic? Anyone here have experience with such amps and medium efficiency speakers like these?

That's probably a good question for Alan.
You might want to send him a PM.

Hi FlaCharlie
I don't think you have anything to worry about. SET tube amps clip soft, not like solid state amps. I like your speakers! I use either a pair of M55s or M66s with a 5 watt per channel tube amp, and every time, that is every time, I listen to that system, I'm all smiles. Sweet, sweet music. I've also used it with a pair of M3Tis, also beautiful. BTW, I modded a pair of M55s with Jensen paper oil caps, Caddock resistors, and Cardas silver wire. Those modded M55s sound ever better than stock which sound spectacular in their own right.

But the M66s are awesome with the SET amp.

G'luck with your set up. Did I buy my M66s from you? Your user name is familiar.

Hi Philip - yeah, you did buy a pair of M-66's from me a while back. I'm glad you're enjoying them so much. I thought you might respond to my question since you use a low power tube amp. It's good to get some input from someone who has real experience with this type of setup. I would hate to damage anything in this setup - these low power tube amps do sound incredible. The guys who insist that you need 100db efficient speakers with them must like to listen REALLY loud. On the rare occasions that I want to listen louder than the SET is comfortable with I have a variety of vintage tube amps that also sound great but the SET does have a magic all its own. I wonder if Axiom has ever considered building high efficiency speakers? . . . Charlie

Axioms are pretty darn efficient, and work really well with low power SET amps. Once you kick back with either the M55s or M66s with your SET you will love what you hear. Same for M3Tis, and larger Axioms.