High value, high efficiency speakers for SET amps


Hi, Gang,
I know that some of what I want to discuss here has been dealt with in other threads, some of them quite old, but I wanted to see if any of you fine, knowledgable folks are willing to help update and consolidate some of this info in a more current thread.
I am currently running my new Audio Note Kit 1 300B SET amp with a pair of Reference 3A De Capo speakers. I think it's a fine pairing and I am really enjoying what the 300B SET experience brings to the table in terms of musicality and emotional connection.
Still the De Capo, while supposedly an easy load due to its crossover-less design (only 1 cap on the tweeter with the mid-woofer directly coupled to the amp), is "only" rated at 92 db efficient, and based on the most recent Canadian NRC specs, that rating may be optimistic.
So, I am toying with the idea of trying a pair of more efficient, deliberately SET-friendly speakers in my rig, something that might also play lower and with greater dynamic swing than the De Capo's. Note that the De Capo's have served me well and I am very fond of them, but I can't help but wonder if my lovely Kit 1 would shine even better coupled to a VERY easy to drive speaker.
Devore and Audio Note are obvious options - the O/96 looks really tasty. Unfortunately, both of those choices are out of my budget, which I'm thinking maxes out (for real) at around $1500. I am willing to consider used equipment.
Tekton Lore 2.0: This is the speaker that Eric Alexander of Tekton has recommended when we've spoken on the phone, based upon my medium-small listening room and amp. I've read the epic "Lore vs. Zu" thread elsewhere in this forum, and clearly Tekton has its enthusiastic fans here. What I wonder is whether the Lore 2.0 has the refinement of the De Capo in terms of resolution, sweet high end and imaging. Audiogon'er Mikirob has pointed me to the many rave reviews of Tekton's speakers and I'm definitely interested.
I've corresponded with the Sonist folks (who are super nice) but their really high-efficiency, nearly-full-range floor stander is out of my budget.
Then there's the "vintage" route, going after some used JBL's or other high-efficiency "classics" from the 80's (or '70's). I am not inclined to go in this direction, but mention it because it's been suggested to me.
And then there's Omega. I spoke to Louis some time ago and he recommended his 7XRS hemp cone model. But I know all the raps on single driver designs and I'm cautious, although I would like to hear from any of you who own or have owned Omega's.
I'm in no rush to make a switch but I am very interested in your thoughts. Thanks, folks!
rebbi
So, Atmasphere,
Then why don't we have manufacting that promotes high efficiency nominal 8 ohm or higher speakers. Seems like it makes amp manufacting funnel into a narrow "limiting" high power proposition that does Limit and force a specific choice that doesn't often times serve music by my definition, but does loud/dynamic. As a maker of a fine amp, don't you realize many benefits with more efficient speakers in the manufacturing process.

I'm a big advocate of high efficiency- tube power is expensive! My speakers at home are 98 db and 60 watts is pretty good power on them and I don't feel like the extra power is wasted at all. I like to play things at a lifelike level. I'm also an advocate of higher impedance- 8 ohms or more. This reduces the distortion of all amplifiers, tube, solid state, class D, whatever. Higher impedance is also a lot less critical of speaker cables and connections! IOW if high quality reproduction is your goal, there really is no good reason to use a 4 ohm speaker. If sound pressure is your goal and you have solid state then there is a reason, albeit a 3 db reason... it would be cool if speaker manufacturers figured this out as a simple way to make any speaker sound smoother and more detailed is to reduce the distortion of the amp by increasing the impedance of the speaker.

Ralph I stand by my statement that there is no perfect amplifier, some will excel in some sonic areas and be less than ideal in another. We choose the tradeoffs we can live with.

Restated in this fashion I've got no beef; I agree 100%.

One of the huge strengths of SETs that many audiophiles don't realize is that 'first watt'. SETs might make a lot of distortion at full power, but as the power output is reduced the distortion decreases linearly to unmeasurable- at lower power levels most push-pull amps make a lot more distortion (one of the few exceptions being our OTLs which have the same reduction of distortion as power is reduced). This is where that great 'inner detail' and 'magic' comes from- without distortion you just get the music (distortion masks low level detail via the ear's masking principle).

That's a lot harder to do than it sounds!

This is why if you really want to hear what the amp does you need a speaker with real efficiency.
Jetrexpro, you nailed it. Well done sir. One 8 or 10 watt SET amp can play much louder than another 8 watt SET amp without the distortion Ralph talks about, if the amp has a robust power supply and iron.

10 watts is not created equal in all 10 watt SET amps. One amp may run out of gas well before another based on power supply and iron. This has certainly been my experience. My current 10 watt SET amp drives my 90-92db 8 ohm speakers wonderfully. A past 12 watt SET amp ran out of gas!
Grannyring,
Agree, the same rating doesn't mean they're the same amplifier by any means.
Pehare if the Dynamo didn't suit your needs then yes you should move on. One point though, don't confuse the Dynamo with the Frankenstein. Yes they're both 8 watt amplifiers yet are in reality very different. Very different design objectives, far more power supply and trannsformer capacity for the Frankenstein MK II. The Franks are 3 times as heavy as the Dynamo for a good reason. Note the comments of Jetrexpro and Grannyring regarding power supply quality and grunt. This factor and output transformers make or break SETs and thus a hierarchy is established. Franks drive the Coincident Total Eclipse brilliantly.
Charles,
Tubegroover,
There's absolutely no offense taken by any stretch of the imagination. We're just all sharing our varied experiences and opinions. The irony for me is that the SET ownere here as a group are about as an experienced bunch you'll ever find. We've as a group have owned or experienced a multitude of different amplifiers and by this time and place know what we want and how to get it. Class A, AB, D, SS or tube, OTL push pull, you name it and we've heard them collectively. Those of us who've chosen SET did so willingly, enthusiastically and with both eyes open. This has been a good discussion.
Charles,
The key to good sound is all about low noise and distortion.

Agree with Ralph that a major difference and potential advantage of a set is that first watt or so and results will depend on how far you can make that go.