Why do SETs sound so good?

[tube fanatic]

Deckert makes an excellent case for SETs.  His statement in regard to feedback, "Feedback a problem? If you don’t mind the time smear it creates and the resulting 2 dimensional sound stage, then no I guess it’s probably not" is also interesting.  By "time smear" I imagine he's referring to phase distortion.  Long ago with my SEP designs, which must use some nfb to get the desired bandwidth, I stopped using global feedback from the opt secondary because I was convinced that I could actually hear the phase distortion.  By switching to some simple voltage feedback at the output stage only, I no longer hear that effect.  Regarding the soundstage, I agree with that also.  With too much nfb I also experience a very definite collapse of the stage both in terms of width and depth.  My late friend Frank developed a very interesting SET design in collaboration with European designer Claus Byrith which employed variable feedback as a means of demonstrating its effect on soundstage.  Although I never heard it, Frank stated that he could go from a huge 3 dimensional stage to one that was basically "flat" by simply adjusting the fb control.  I don't use any fb in my SETs.

William, I'd bet that if you measured the amount of power you're actually using when listening it would not be more than 1/4 wpc which gives you around 9 db of headroom.  In my world, that's plenty!  Also, at that power output, the distortion of the amp is extremely low as well which contributes to the phenomenal sound you're experiencing.  I didn't go back and look at the parameters, but I think the measured 2nd harmonic distortion at 1 watt out was only 2%.

 

We're fortunate that Klipsch continues to make speakers which are so efficient that low power tube amps can be used with ease.  In my experience, both the Heritage and Reference series speakers are capable of providing an enormous soundstage when driven by amps which allow them to flourish.  I have never heard solid state amps which can do the same with Klipsch speakers.

Maynard  

[jcmusic]

With out trying to hurt anyone's feelings are stir up a bunch of flack!!! I don't really care WHY SET amps sound so good, I just know that when I hear it it sounds good and I like that!!!