High efficiency speakers

I am getting into low wattage SET amps (specifically the 18w Lamm ML2.1). I am told that to realize the full benefits of such low powered SETs, you need high efficiency (>95db) speakers with benign impedance curve. But when I look around, these speakers are often horn based, huge and unattractive (to my eyes), and have problems with low bass (either no low bass or needs powered woofers whose integration is a problem).
My question to the experts out there. Have you come across well designed high efficiency speakers that are full range, don't take space like Avantgarde Trios, and look as nice as a Kharma?
Thanks for your suggestions.
Coincident from Israel Blume.
I'll second Coincidents-I'm using them with 20 watt SET's and have tons of power.
95db is pushing it, 92db or better will be great. 90db will possibly cut it.
Check out www.daedalusaudio.com

If you are considering a pair of DA-1's, drop me a line, as I am likely moving on to one of the newer models.

Seriously, the Daedalus speakers are high efficiency and incredibly musical.
KCS loudspeakers offers hi-eff loudspeakers that are not horn based. Where a custom shop so most anything goes;)
you might look at devore silverbacks -- i ended up with trios but when i was auditioning speakers i also liked the silverbacks
Take a look a the WLM line of speakers now distributed by Red Wine Audio. I haven't heard them but the reviews have been good so far. On the more affordable side of the scale, look at Omega.
Silverline. Though check discussion threads for synergy of specific models with SETs.
I am using a 16 watt Art Audio Carissa to drive the 92 db Von Schweikert VR4sr mk2. This is a great match. The VS speakers higher up in the line are more efficient and all are full range. Hope this helps.

Blessings, Bob
When talking about low powered amps and high efficiency, it's all relative. 18 W is not really that low powered and you have a lot more options. Personally, I prefer ultra high efficiency speakers no matter how much power. When I mean high efficiency, that is certainly 97 dB or higher.

Based on your conditions, there are many possibilities. I would recommend a speaker built around a PHY-HP driver. Check out either Ocellia, Musical Affairs, Tonian Labs.


These are 97 dB and have deep bass. I wouldn't rule out horns entirely. Depending on what you consider huge, you can check out several Altec/GPa 604 based speakers. I use a 604 based speaker but my speakers are huge.


There are also a bunch of back loaded horn speakers that are fairly compact and conventional looking. The Feastrex based Maxxhorn speaker is pretty cool.

http://www.lovecraftdesigns.com/index.html (formerly Cain and Cain)


Along more conventional lines, the speakers mentioned above like Coincident, Devore, etc. would all probably work. Many of those are not really high efficiency but with 18 W many would work just fine. Those speakers would require more careful matching in terms of power since it is borderline. The speakers I suggested would all work in terms of power and it would be more of an issue of synergy with your amp and personal preferences.
try the yahoo 'SET' forum, they'll have many ideas, as most there have been into SET for years.
Don't ignore the Triangle speakers. They are very efficient and lightening fast. The Celius 202 also earned a Class A rating in Stereophile. And, to be crass about it, I've got a pair I'm about to list on Audiogon.
I have had three pair of Coincidents and one pair of Kharmas. The Coincidents will sound great at 18 watts (I love mine), though nothing will look like the Kharmas. If you need something with that kind of finish, and want powered bass, check out the ZU line.
Zingali horns are beautiful looking, highly sensitive, reasonable in size, and very good sounding at "normal" listening levels(my 3s get a touch "hard" at high spls - although this may be the amps - Cary 300B monos - struggling). Hard to find, but worth checking out.

See a couple of sugestions that I can agree with, but if it were my situation, I'd be looking into Zu Audio, which I've owned and used with an 8w/ch 300B amp and Rethm Saadhana. Great amps hope you find the right match.
That 18-watt Lamm amp really gives you more options than most single-ended triode amps do. I think you can reasonably look at speakers below 95 dB efficiency, assuming a benign impedance curve. I've shown benign 92-dB speakers with SET amps of 5, 6, 12 and 25 watts, and the only time we ran into audible clipping was with very loud solo piano on the 5-watt amp, and real-world that conservatively rated Lamm amp is probably more powerful than the 25-watter.

Hi all, thank you for your suggestions. I have the Kharma 3.2.2s which are borderline efficient at 90dB and not getting the full benefits of the SET design from what I've been told, but probably Ok in my current smallish room. Going forward I am looking for full range SET friendly, high efficiency speakers. No more of the Kharma limp bass I hope. I do have pre-conceived biases against side-firing woofers and powered woofers, but maybe unfounded.
I'll echo the suggestion of Coincident and Silverline. Both have excellent SET-friendly solutions. With your bias against d"Appolito alignment might eliminate Coincident though they sure sound great to me. I heard Daedalus speakers sounding absolutely superb at their room at RMAF and I believe that was with ArtAudio SET amplification. They have a very specific look to them as well using some interesting joinery on the cabinets which I'd imagine wouldn't be everyone's taste, though I thought they looked and sounded great.
Jax2, I haven't had the pleasure of hearing the Concident. My bias against side firing woofers is from listening to one of the models from Rockport. I heard less integrated bass, the same way some people would say about the rear firing woofers of the Verity speakers. My bias against powered bass in high efficiecy speakers is just a thought that since these designs use transistor amps for ther woofers, are they forgoing the supposedly sonic superiority of SET over SS amps (even in the bass quality.)?
I would agree with the posters who say do not rule out horns. Horns are the perfect match up for tube amps of all types, and many of them have 100 dB or more efficiency. There are many horn speakers out there with great bass. Altec Lansing made some incredible speakers, as an earlier poster mentioned. JBL did as well, and Klipsch made some great ones too. You can still find some "vintage" Klipsch speakers at very reasonable prices on the used market. I own a pair of Klipsch Cornwall II's which have fantastic bass. I am not as familiar with some of the newer horn designs, as most are European and hard to find over here, and I would tend to be skeptical of any design incorporating a subwoofer in any case.
ZU Druids. 103 DB and a wonderful speaker. Bass galore and unified sound as it uses a single drive plus a super tweeter. BTW - they move quickly when they come up on Gon. I've had mine for about 3 months and have fallen head over heals for these babies. An added plus, they are bottom-ported so you can put them within inches of a wall. I use mine for nearfield listening and they bested Magenpans, Mark and Daniel Rubys as well as Gallo Dues (though these others are not high efficiency speakers).
I understand your problem perfectly, because I embarked on a similar journey myself. Click on "my system" to see what I ended up with. My setup is not without its problems but I am working on a solution to it.

The problem with hi-fi is that you can go the "accurate" route, which usually means big SS amps and ineffecient speakers, or you can go the "high efficiency" route. The former gives you accurate but sterile sound, the latter has benefits of simpler electronics, extremely fast speakers, purer sound, but usually involves compromises such as cost, size, coloration, and lack of bass. This is a harder route to take, and you will have to think hard and match carefully if you are going to succeed.

There are a few types of designs you might like to consider. Front loaded horns (e.g. Avantgarde), back loaded horns (Lowther, Rethm, Tannoy), high efficiency conventional speakers (WLM, Zu), and compression drivers are the main technologies involved.

By far the most similar to speakers you are used to would be speakers by WLM and Zu. I have heard both - not a fan of the Zu, but I do like the WLM's very much. As a bonus, they are very reasonably priced.

The Tannoys would be a good pick if you could get over the styling. They are by no means uncolored - in fact they are very heavily colored. But it's a very appealing kind of sound.
Dukes Audiokinesis loudspeakers might run on your 18 watts hes a great guy products very well though out.
Amfibius, your Acapella speakers look very cool indeed. Aesthetics is important to me. While my little Kharma's are not perfect match for my soon-to-arrive SET amps, and have limp bass, at least my wife doesn't complain. If i brought in the Avangarde Trios, I think she would scream:). So I need to avoid big broad cabinet designs if I could and there goes Tannoy.
My bias against powered bass in high efficiecy speakers is just a thought that since these designs use transistor amps for ther woofers, are they forgoing the supposedly sonic superiority of SET over SS amps (even in the bass quality.)?

I don't know how you would actually like it, but before you jump to conclusions about it you should perhaps try listening to some implementations of what you are describing here (basically you're talking about bi-amping). I do think it takes some skill and knowledge, but have heard it done well, though I cannot say it was with a SET amp in the mix. As far as the sonic 'superiority' of SET over SS - IMO (this is coming from a big SET fan who has used 300B 8 watt SET amps in my main system for around 8 or 9 years now) the allure of SET is all in the midrange purity and that magical holography that no other type of amp does so well (OTL is a nice alternative though and comes pretty damn close). I haven't heard any SET amps that can do tight convincing bass as well as an SS amp - that's not to say one doesn't exist, but I haven't heard it if it does. When it comes to pushing those larger woofers that really move a lot of air fast to create the convincing bass, the lower powered amps just are not up to the task when compared to more powerful alternatives. I'd also highly recommend SET and horns, and would have mentioned vintage Klipsch as well but your tastes seem to run in the more exotic realms. Klipschhorns and SET were made for each other. Horns and SET in general are a great match, but they can also be a matter of taste as the sound is unique. I love it myself, but have also heard front loaded horns that bore me to tears or make me want to go running from the room. I tried Zu Druids for a while and didn't warm up to them at all. The success of your implementation of SET and a particular pair of speakers will also be determined by the kind of music you listen to, how loud you like to listen, and the volume of the room you are listening in. Most of the music I like the best is well suited to SET - it is simple, acoustic and or vocals in small arrangements. If you are into densely arranged orchestral, jazz or rock music IMO there are better choices in amplification than SET, and the idea of 'superiority' goes right out the window in comparison with an excellent SS amp when listening to these materials regularly. In this sense SET is kind of a one-trick-pony. It is certainly not the Swiss army knife of amplification. Don't get me wrong, I love what it does well - in those realms it is king when put together with the right speakers. You are right to carefully research that specific interface as it is more critical than ever when using a SET amplifier.

Good luck!
Specs don't always tell the whole story.

My ProAc Response 2.5s are rated at 8 ohms and 86 dB. When John Atkinson measured them back in the day, he calculated 83 dB!

Yet they work wonderfully well with my Cary 300B-based SET, rated at a whopping 14 watts!

Part of it is the real-world (not claimed!) 8 ohm load--Atkinson's graph shows them barely dipping below 8 over the whole 20-20k range.

BTW, I was turned on to this synergistic combination years ago by Arnie (founder of A'gon) in his previous incarnation as owner of Accutronics of Ann Arbor, MI. According to Arnie, Dennis Had used (at least back then) ProAcs to voice his Cary amps.
>>ZU Druids. 103 DB and a wonderful speaker. Bass galore<<

Zu Druid is rated at 101dB but might even be lower.

"Bass galore" is overstated. The bass is adequate but not great.

Dealer disclaimer.

No offense intended, but how did you come to owning a Lamm ML 2.1 without much experience with Hi-eff speakers?
I am using Reimer Tetons with my ML2's to great effect. They are full range and have a nice tight bottom end with the ML2's.
Hi Jax2, your advice noted. I listened mostly to light classics and folks, and occasionally big scale music. My current room is only 10' x 14'. I have an opportunity to build a bigger one (perhaps 18' x 20'). The hi efficiency speakers are meant for that room for which I would like full-range and life-sized reproduction of the music I love. For many years till recently, I have always used SS amps...Classe, Pass labs, Goldmund. Just my experience, they had been good in many ways. But at the end of the days, i feel them collectively to be a little cold and sterile.

Hi Darkmoebius, I have a pair of Kharma 3.2.2 (borderline efficient at 90dB) driven by Goldmund Telos amps. I wasn't touched by the combination. Since the matching of kharma and Lamm has been well chronicled, I ordered the Lamm ML2.1s at risk without hearing. But I did phone up the Kharma factory and was told the ML2.1s are "perfect match" for my speakers. The amps haven't arrived, so I shall see.
Jax I use SETs and play rock, punk, pipe organ ,etc most every type of music. I never feel limited by my SET horns systems I play whatever I want. If loudspeakers and SET both are well matched I can play most any SPL level off 1 SET amp. Ive even used a SET horn system at a outdoor biker rally and at my sons school gym. And these are musical horns designed for hi-end audio use not PA. And some bass systems dont need large SS power if designed for low power or SET so not all large bass drivers need large power. Also since SET powers not just 2-8 watts many SETs have more these are not as limiting. I will also end by saying I greatly enjoy 300b but most if not all 300b amps are rolled off after 40hz. Ive owned many some of the best all have been weak in bass compared to other SET designs. And drivers are not moving air as much as exciting it by pressure wave like ripples in water.
I recently purchased a pair of Tonian Labs TL-D1 speakers after hearing them in a home demo coordinated with Tony Minasian, the designer. They are rated at 95 db with a frequency range of 42 hz to 40K hz and a benign 8 ohm impedance. Measuring 33"H x 11W x 17"D they are a simple two way design with an 8" Fostex driver and a modified ribbon super tweeter. They feature a minimal crossover and come with three different sized wooden plates that vary the rear vent size to adjust the bass output for the room.

I found that the TL-D1's worked better in my small (10.5'W x 12'L x 8'H) room than a pair of Audio Note AN/J speakers that I have owned for the past eleven years. The AN/J's sound great in larger rooms but in my smaller room they could be a bit boomy at times with a 50 hz peak due to a primary room mode. Not so with the TL-D1's which have a smoother frequency response in my room.

For amplification I've used an Audio Note M1 pre and P2 SE (18 wpc) amp and a Red Wine Audio Signature 30 (30 wpc) integrated amp. Currently I favor the RWA amp with the Tonian speakers which are still breaking in and are becoming more open and extended at both ends with use. Time will tell which choice of amplification wins out but neither lack in power with an eclectic range of music.

Not much has been written about these speakers, but there is a recent Positive Feedback review at http://www.positive-feedback.com/Issue36/tonian_labs.htm that I found to be in line with my experience with the speakers.

Whether the TL-D1 speakers will be a good match with your amp and room I couldn't say, but they definitely work very well for me. Given their musical capabilities I would consider them one of the best values in speakers. Tony also makes other speakers based on the PHY drivers that reputedly offer more refinement and realism, but at a much higher price.

Good luck with your quest.
But I did phone up the Kharma factory and was told the ML2.1s are "perfect match" for my speakers.
Aaaaah, that makes sense. I was hoping that you didn't just pick a reference SET amp and hope it would work.
Hey JohnK - I believe you, and am glad to hear it. Please note, I did not say that SET amps could not play rock, punk or pipe organ music. I've also played and enjoyed all that as well as orchestral and other dense and challenging source material with SET and horns. I did not say it was necessarily a bad combination. I only stated that it was my opinion that the denser source material is better served by SS amps in comparison (IMO, of course - you may feel differently). I have not heard any SET amp / speaker combos that serve that type of material better than SS, but there are many out there and I've only listened to a relatively small amount of what's available between shows, dealers and friends, as well as the few I've had at home. So many amps, so little time! Seems like the SET stuff that I have heard that does better with denser material are parallel SET solutions mostly that put out a bit more power. Bel Canto's SET amps were pretty nice in that respect too. I'm glad to hear that more is possible than my experience leads me to believe. It does not surprise me. I've seen some of the unique speakers you've sold here and they certainly look interesting (with much emphasis on bass cabinets as I recall). Thanks also for the clarification on the physics of drivers! As I understand it, transformers also play a big roll in successful implementation of SET topology. I've been using a pair of Mike Sanders Quicksilver 300B SET amps. They're not on his site, but he had a pair at the recent RMAF and was also playing his KT88 based SET amps there as well. Love'em. They do have what seems to be a better bass response than a few other 300B's I've been able to compare them directly too (Wavelength and Wright Sound). That said I don't think bass is a 300B's strong suit. The horns that I've seemed to like the most take up a whole lot of space and need room to breath. While the smaller solutions don't really excite me much. I've recently had to give up my larger workspace and bring my system home and I've been having a hell of a time missing those horns. My modified LaScalas are just too big for my modestly sized home. I've tried a few different speakers looking for that speed and dynamics of horns. Coincident has come the closest with a very similar clarity as well, without any edginess at all. Damn fine speakers, but ultimately I do think they're in need of a bit more power to really sing in my room (the volume of which is rather large overall, while listening is practically nearfield). They do great with the 300B's otherwise except for the deepest of bass notes. If I were in a smaller room I think they might be perfect. 300b's with horns is nirvana for me with much of the music I prefer, but I don't think it is necessarily everyone else's, and I don't think that I might not enjoy other alternatives (and have certainly done just that).
Alectiong, as others have said having 18 watts gives you the luxury that many SETs don't give you. I loved my Reimyo PAT777 amp but bought Acapella LaCampanellas at 92 db. The 8 watt Reimyo just could perform as it had with the Beauhorn Virtuosos at 103 db. But the Beauhorns were dying at 60 Hz and Murata super tweeters helped a lot. But with no crossover, the Beauhorns were wonderous where they worked.

The guy that bought my Reimyo uses Avantgarde Trios and absolutely love it. I think your requirements realistically cannot be met. The Zus would work, but I have never been a fan. Were you not to have your space requirement I would recommend the Klipshorns, which still seem to me to be the best efficient speakers. I have owned them three times in my 45 year audio experience and often wonder why I ever moved away from them. They do have to be in corners, which was my reason for selling the first two pairs. Now, however, I could put them in the corners with no hole in the center.

The bad new is that there really is no good solution for you. It'd be best for you to sell your Lamm amps now - mail me and I'll make a fair offer.

But, if you're going to keep them, you need to look into Audio Note speakers.
You might try the Classic Audio Reproductions if you have the budget: 97db 1 watt/1 meter, 16 ohms, 20Hz-45KHz and the 20Hz is bona-fide. I have found very little to complain about in this speaker: the resolution (with the field coil drivers) equal to the best ESLs, imaging and delicacy to match. OTOH they are the size of small refrigerators, but they work great even if only 6" from the rear wall.

If you are on more of a budget, the ZU Druid (the new version) is not bad; I found that while the Audiokinesis was not *rated* the same efficiency, that it *behaved* as if it was just as efficient, but with greater bass impact and more definition.
Paul, I read your AN review on AA you say only 2 days use? Is this correct? Where drivers etc broken in before you purchased? Thank you
Hi, I finally received my Lamm ML2.1's, and am burning them in. I haven't gotten myself a pair of high efficiency speakers yet. I am still using the Kharma 3.2.2. I have a qn to ask and hope someone can enlighten me.
The ML2.1's have 4, 8, and 16 ohm taps. My speaker's nominal impedance is 4 ohm (and can dip to 3.5 ohm). My assumption is to use the 4 ohm taps of the ML2.1's. But if so, what is the technical reason for that? And is there any reason to try out the higher ohm taps? And if yes, why?