Need help : Single ended, Low power, SET amps..

Can someone help me to understand the + and - of Low Power? SET? Single Ended? And a few examples of some models would help.
Try looking up the triode guild on Eccentric, irreverent, thought provoking and informative if you can cope with an intellegent very anti pollitically correct approach that is not as sexist as it appears once you get past the surface.
General idea is you don't need heaps of power if you have around 105 dB per watt efficiency. 3 watts will go as loud as 200 watts into average efficiency speakers, i.e. 86 dB.
Go listen to someting like Klipshorn La Scala speakers suitably driven. Yes, megabucks including a good system - but so is the high power low efficiency system, probably MORE expensive.
Then have a look at JBL pro gear, for instance their slot tweeter (which is available in 15 ohm versions, ideal for low power tube amps)Try 105 dB maximum output to 22 KHz!. Not even slightly harsh, very quick and detailed. One of the best tweeters I've ever heard - as good as any electrostatic but with real dynamics!
They also do some wonderfull mid and mid/high horns, like the so-called "but cheek" or "Dolly Parton" horn. 500 Hz - 16 KHz in one driver!
Their so called "paper" drivers seem to have kevlar and carbon fibre reinforcing the paper. Very light, stiff and efficient.
How about a tube crossover (though I would actually use solid state with tube pre and power - but that is sacrilege!) and bi-amp? 2 - 5 watts of single ended driving a slot and but cheek passively crossed over with 1st order crossover and 10 - 20 watts of push pull triode on bass!

Personally, I like push pull over SE - but listen LOTS to as many different rigs as you can and then TRUST YOUR OWN EARS - cos you have to listen tp it!
Tweek, the plus is that they have low power. The minus is that they have low power. Low power sounds better because of less gain stages, tubes, and complexity.(All else being equal). Low power cannot drive most of the available speakers to a reasonable level, hence the minus. The art is to assemble a SYSTEM that will work to provide both sound quality and reasonable SPL.
Single-ended is generally preferred for great midrange. Since most SETs have output transformers, they suffer from transformer related problems like rolloff and bloat. The best transformer SETs do a very good job at minimizing this and sound absolutely phenomenal. OTL SETs of which there are very few, can be even better, since there is no output transformer. It is generally conceded that SET is superior in the midrange to push-pull. These are all generalizations and each type can be very good depending on the execution of the design. The sound of SETs like all tube amps is very dependant on the type of tubes used. 2A3 is different than 300B. NOS tubes sound different than Russian or Chinese. Etc. Speaker matching is especially critical. Load must match amp well or you will lose some of the little power you have, and impedance matching is also critical for some of the same reasons. If you get it right, the sound quality will be about as good as it gets. And you will get reasonable listening levels with higher efficency ratings of the speakers. A system like this provides enough detail to be ruthlessly revealing of any flaws in the system or recording. If you don't get it right, you WILL hear it. Many people cannot tolerate this level of detail because of this ruthless revealing nature. It can spoil your enjoyment of lesser recordings. But it will greatly enhance your enjoyment of the great ones. Nothing is perfect. This type of system has its strong and weak points. You will never get "rock show" volume levels. You will get awesome small scale sound. Whatever floats your boat.
Tmcroy, your tube xover (Marchand X126) + Single Ended + Bi-amp to push-pull sounds like a winner. But i don't choose my drivers by their db level. I look for what i believe to be superior drivers. Then i look for an appropriate amp. (i'm a Jadis fan). What are the Jadis?... Twl seems in speakers and amps you have a trade off in every choice you make....What i need is one example of Single Ended, Triode, Push Pull, SET. What i can also do is look at all the tube manufactures web sites and there should be descriptions of their amps, i should have something going then.
Tweek, Single Ended Triode is what SET stands for. S is for Single, E is for Ended, and T is for Triode. A good example of one is the Sun 2A3. Another is the Golden Tube 300B. An example of a SET OTL is the Berning Siegfried. An example of a push-pull tube amp is a Marantz 8B(I think?). An example of push-pull OTL is a Berning ZH270 or a Berning MicroZOTL. Regarding the trade-offs, there is a trade-off in every choice that you make in audio no matter what. Everything has its strengths and weaknesses. No product is perfect, even the megabuck ones.
Thanks TWL. I hope one day that your dream comes true, the ZH270 or is it the Siegfried. I'm staying with the push-pull Jadis.
A very good article regarding single ended amplifiers was written by Peter Qvortrup of Audio Note. Go to and click technical on home page. There are two very interesting articles. Of course solid state lovers will surely disagree. Differing opinions is what makes this forum so useful I believe. Get what you can from it and balance it with whatever else you learn. Good luck. As always the proof will be in your ears. :)
Hi Tweek,

Believe it or not, I didn't say JBL just because they are so efficient.

Most hi end people consider the JBL sound is what you get at concerts.
Well sometimes it is, but how would a whole wall of your favourite hi-fi speakers sound, often driven by an "interesting" selection of power amps wired up by people who think fancy cables are snake oil.
Cables being robust so they can be moved 10,000 times is what counts to them - not fancy stranding, teflon or oxygen free!

JBL's are often used in mastering studios. A friend of mine has such a studio and the sound he gets is awesome - of course VERY revealing, which is what SET is like as Twl points out.
If JBL's couldn't get it right - those recordings could never sound right on our hi-fi! (don't assume JBL's are all used for pop recordings either)
Take the best of those drivers (and they are very good, think of the volumes they do, how ruthless the competition is in pro sound and estimate their research budget for yourself), set them up like hi-fi drivers would be and you would be VERY shocked.
I was, and your Jardis gear would be damn fine to drive them - with that much power (even the smallest Jardis) going into speakers of around 100 dB/watt efficiency, bi-amping would be a sonic experement (likely to be rewarding, IMHO) rather than a necesity.

With SET, as with any sort of tube amp, output transformer quality is critical, hence expensive and single ended ones are the hardest to build! Right, = great. Not quite right = oh dear!

If you have pocket deep enough to go 3 way active, how about mosfet or PP tube bass, SET midrange and triode PP trebble? That I think, would be using each type of technology in its strongest area.
Let me know how your hi-fi adventure goes!
hello, single end amps are very simply if you look at signal paths and parts count to me this is why they sound so great but they have to run a speaker with high sensitivity to sound there best .You can run a whole speaker of a s.e.t. amp but they role off the treble and bass some what.So mix and match I say ,if you want a tube amp that can run most speakers than your choice is a push pull .they do tend to distort the signal or stretch notes.they do give you a taste of what tubes can do s.e.t.s give you a so much more musicality than push pulls but they dont do frequincy extremes as offs are what audio is all about
Tweek, check out the Lowther America website. They have improved the Lowther drivers with a re-designed whizzer cone that has a rolled edge. I supposedly eliminates the midrange resonance peak that previously plagued Lowther drivers. They also changed the suspension ring from a rolled out to a rolled in. Smoothed out response there too. New,optional phase plug design is questionable but new just the same. Old one still standard. I just ordered a pair of new DX3 with all the mods. I am making a set of Voight Pipe enclosures to start with and may go to a somewhat more exotic enclosure later. Their new "Big Fun Horn" looks pretty good as a back loaded bass horn design which extends the full-range Lowther down to 32HZ on the low end. Even if it rolls off at 12db from there, it will still only be about 6db down at 24Hz. Not bad for a single driver. Goes to 22kHz at the high end. 98db at 1watt input unloaded. About 100db at 1watt in a cabinet. Not sure if I am all that wild about a corner horn though. Still researching. In any cabinet you choose, though, the Lowther is a great choice for a SET amp. You get great sound with great efficiency and detail with decent accurate bass depth and maybe real good bass depth with the corner horn. Front wave is not horn loaded so it does not "honk" in the mids. How's that? New improved Lowther + Big Fun Horn Cabinet + SET = WOW!! Nothing can touch it! :-) Have fun.
Twl, even though full range Lowthers and Fostex may out-class the commercials, the Seas+Accuton+Philips should provide overall dynamic musicality. The DIY building the speakers says the Push-pull tube is just the thing. I hope one day to hear a Lowther, im sure the imaging is just super and may be more dynamic than a electrostat. Tmcroy, i've looked at active. But i think a superior passive xover in parts and in tweaked design (DIY) will allow the amp to deliver a better sound. Between amp and drivers , least is best. John, trade offs in amps is an issue. I could not sacrifice the FQ's in the high and low end with a good SET. I won't know the potential of this Jadis until i get the new speakers. MY B&W's and Philips lack finesse.
My dream single ended amp is the Berning Siegfried. Someday, maybe........ :)
I recently purchased a Terra Engineering Star 10. It uses el34, kt88, or 6550 tubes. It puts out ten watts and has a volume control. I have to admit, this little monster can bring across low level detail like I've never heard before. I generally prefer my ARC vt100/bat vk-5i setup, but there are parts of a recording that only the SET amp can bring accross.

I have it hooked up to my mcintosh mr71 tube tuner and a set of (believe it or not) Gallo Nucleas Micro's. The micros are 92db efficient. There is not a lot of weight behind the instruments, so you seem to be listening to a very detailed, delicate 'sonic image' of the instruments that is 'floating' in the soundstage. Some of this is a characteristic of the Gallo's, but I hear a similar effect when I hook the underpowered terra to my audio physic avanti's, or my Spica TC-60's.

Like tax rules, there is a surrealistic quality to them. It's not quite reality, but some aspects come across more perfectly than any amp I've heard. Bass guitar for example does not sound real at all - it's very distant, weak, and shallow sounding, but you hear the fingering more. Violins, Trumpet and the upper register of a piano sound more detailed and intricately textured than I've ever heard. The plink is just right.

Vocals are affected similarly. You hear more delicate inflections, but some information is also lost. Jesse Norman does not come accross as being ten times more powerful than Chet Baker, yet you hear Chet's sad ass, no smiles for miles wimpering more distinctly than ever before.

I played trumpet 20 years ago. I realized when listening to the set amp that I could hear the air rushing through and resonating with the instrument's brass. Blow into a plastic diet coke bottle (you know, the whislin sound), then image a 100 Watt ARC tube amp trying to replicate that sound. The arc amp can't do it, the SET amp can.
John, welcome to our world. Now, the next step is to get that magic into the rest of the frequency band too. This is what we are all working on. Not easy, but fun.