The problem is you need efficiency to really hear what the amp can do.
With any SET, your normal high volume listening level should not exceed about 20-25% of full power that the amp makes, due to the excess distortion that will occur. The distortion manifests as 'dynamics' due to how the distortion components interact with the human ear.
This is one of the reasons people often think or say that 'its loud enough'; its not because it actually is- the 'loudness' they hear is being caused by distortion, not actual sound pressure.
The reason this is so is that the ear uses the higher ordered harmonics to sense sound pressure. When higher ordered harmonic distortion is present, the result is that it sounds louder when it really isn't.
To avoid this, a more efficient speaker is needed. If you want something smaller, about the only game in town is a higher efficiency full range driver, like a Lowther or PHY.
PHY has offered an open back cabinet for their 8" driver that is actually not very large and isn't expensive. Its good down to about 60 Hz or so and sounds pretty decent. Its efficiency is about 99db with the PHY driver. I'm not a fan of PHY, mostly because the product is not well supported after the fact (we had to recone one once and getting the parts was a nightmare- PHY was being pretty precious about them). But if you really want to hear what a lower power SET actually does, you need this sort of efficiency in most rooms.
In truth a horn system of 105db or more would be better, but that is hardly 'monitor' sized.
@soundrealaudioI i can explain my philosophy which i used before
with Bache Audio -002
You have 8 watt tube power. Ok , No more, you have to use this Revenue 8 to power midrange and tweeter. No more power to get
good sound , just 8 watts, From 700hz and up to 20000, you need
high sensitivity wideband driver and tweeter. External subwoofer
does not good in this situation . you need extra midwoofer 5-6" but you
cannot find midbass with sensitivity more 90db. So we used active buld
in small amps with crossover point 700hz. But dont worry , is not important , it will be driven just midbass, it not will be affected to tube sound
I have a pair of Air Tight AL-05 monitors which I run with the Air Tight 300 B (30th Anniversary) amp. Just unbelievable. Only a 4" driver, but out of this world clarity, coherence, sound stage, blah, blah. Very reasonable if you can find them. I paid 1300 used, new I think they are only 2500.00. I recently added a low powered REL sub, just because I could, but they really don't need it.
My two cents, but I do have three systems, a lot of experience. I also run ESL 57's (refurbished by Wayne Piquet, Quads Unlimited) on a Air Tight KT88 amp, (in the same room) and it's kind of a toss up, both are extremely good.
I used AudioNote 300b's with Reference 3A decapo's (be) for over a year and half before I moved on to a Pass 30.8. The Decapo's with the audionote amps were very seductive, their imaging and instrumental tonality was just wonderful. I spent many late nights listening to music with this setup. On a couple of nights while listening to Eva Cassidy's "live at blues ally" I actually thought she was standing/sitting in front of me. And no I was not using any pharmaceutical enhancement.
For several happy years, I enjoyed the music making company of my Audio Note Kits "Kit 1" 300 B SET amplifier, which I built with my own two hands (loved the experience). As documented on my blog, here, I eventually learned that although sensitivity ratings (the stuff you see quoted in decibels in manufacturer's literature) are certainly important in finding a good match for a low powered, single ended amplifier, it doesn't tell the whole story. I thought that my Spatial M3 Turbo S speakers sounded splendid with that single ended amp, and they did… until I happened to hear the same speakers with a high-powered, solid-state amp that I had borrowed and that seemed to make everything I like about the Spatial's a lot better. When I spoke with Clayton Shaw of Spatial to ask him why, he explained that sensitivity is part of the story (and an important part, since ideally you want a SET amplifier to be operating within its "1st watt” for lowest distortion), but you also have to take into account the impedance curve of the speaker – how difficult or easy a load is it for the amplifier to drive properly? And in that regard, the standard M3 Turbo S was not going to be a particularly great match for a SET amp.
By the way, I ran my Reference 3A De Capo monitors (which I loved) with that 300 B amp for quite a while. It sounded lovely, but it turns out that the sensitivity ratings given by the manufacturer are somewhat optimistic. It's not a slam on the manufacturer or the speaker – both are great – but there doesn't seem to be any standard way of determining sensitivity, and the question is always, across what part of the frequency spectrum is the speaker that sensitive?
Anyway, let me toss out a somewhat out-of-the-box suggestion. You might take a look at the very well reviewed Fritz Speakers Carbon 7's. Although the sensitivity ratings of Fritz's monitors are not at first glance especially high, their impedance curve tends to be nice and flat and an easy amp load due, in part, to the series crossovers that Fritz uses. Plus, Fritz is a sweetheart to deal with. Anyway, here is my review of the Carbon 7 SE speaker paired with my old 300 B amp. Enjoy.
I enjoy very much a pair of Omega Super Alnico Monitors.
I heard there was a cult following for this speaker before I bought it.
Now I know why. Just an amazing speaker for a 300b amp. It is 94db and sounds just as good with my 4 watt parallel 45 EML mesh tubes. Actually the 45 tubes are slightly more intimate than 300b's but have less power.
The Omega's never gets past 4 o'clock on the volume. They are so easy to drive and so revealing and natural without any crossover.
I have speakers worth ten times the price, and the Omega's are very special because even though they can't do everything, what they do right, is just bliss.
I have tried Totem Model One's monitors at 87.5db with the 8 watt 300b amp. It does sound Ok but the Omega's sound so much better. At 11w x 20h x 14d , the omega's are a large monitor.
Maybe one day I will try the smaller Omega Super 7 Monitor Mk2 at only 9w x 15h x 12.5d.