High Efficiency Speakers Your top 3 or more

I've heard the Classic Audio Loudspeaker, both T-1 and T-3 many times. The recent field-coil versions are remarkable. They are faster and just as detailed as the best electrostatics, yet very relaxed, and image easily. They are also very cohesive. The beryllium diaphragms used are custom-built. The have no breakups until about 40KHz, so the speakers are exceptionally smooth, even more than the Cogent, which uses phenolic diaphragms (or at least, did the last time I heard them).

The speaker also is easy to set up- you don't have to have it far from the walls to make it image well. It has bandwidth to 20Hz, and is about 99 db 1 watt/1 meter and 16 ohms. So you can shake the walls with a fairly small amplifier. IOW not only is this one of the best speakers you can buy at any price, but it is also easy to drive.

Most high efficiency speakers have fairly tight tolerances in the voice coil gap which makes them very reactive. The back EMF they present to amplifiers that use a lot of feedback is enough to confound the amplifier, as the feedback signal thus contains induced errors.

This is why transistors in general tend to sound shrill on horns and why horns had such a difficult road back into high end audio in the last 20 years- the bad rap of a bad combination.

However if not so much a tube/transistor thing as it is the amount of feedback used by the amplifier. Transistors do tend to use a lot more than tubes, and there are tube amps that don't use any. There are some transistor amps that don't any feedback also and not surprisingly they don't do so bad on horns.

I heard the new field-coil Shindo speaker at THE Show. It seemed to have some potential (no pun intended) but was clearly not playing the bass that you would expect out of a driver and cabinet that large. The material I played has information in the mid-20s, and my suspicion is that the Ongaku amplifiers that were being asked to play the bottom end were simply not up to the task, but its only a suspicion. When hearing any system there is always the tendency to place the blame of shortcomings where your biases lie... regardless, I think that the speaker they showed is really something to watch.

I'd really like to see how it stacks up against the Classic Audio stuff- they cost twice as much as the Classic Audio speakers do.

Mapman, although I prefer OTLs myself :) if I had a set of field-coil powered Classic Audio Loudspeakers (which are about 99-100 db, about 3 db more than their Alnico versions), I would not hesitate to try out one of the DeHavallind SETs and treat it with lots of bass-heavy techno material.

I listen to a lot of this stuff at home- I guess you could say I demand a lot out of my system, so I know that with the right speaker you could do that with the right SETs.

We have what we call the 'Atma-Sphere Bass of the Year' award, see
http://www.atma-sphere.com/awards/bya/index.html
I've seen some of these recordings throw some well-known speakers right on their respective faces...

Tvad, we are not so strict about the loading on the M-60. I've seen it work fine with speakers that dip to 4 ohms at crossover points, IMO its always something that you try and see how it works. But Thom has had his M-60s for well over a year and a half and seems to really like the combination, so it seems that they are a good match. He's pretty demanding.