Welcome to the wonderful world of high efficiency!
You asked for specific recommendations, so I’d like to mention some high efficiency speakers that I think have particular merit. Since I’m a dealer I’m not supposed to blatantly recommend stuff that I peddle here at the Asylum, but I am going to mention a few brands that I sell and use “in the interest of completeness” as my excuse.
In alphabetical order:
AAA Audio XLH 1812's: Enormous and very high quality horn/woofer hybrid system from China, using JBL components. Don’t let the China part put you off - this system has world-class dynamics and impact. Uses giant “Queen Latifa Buttcheeks” horn. You gotta see this, so I’ve provided a link below.
Altec Lansing: The Model 19 and Model 14, long since discontinued, are excellent speakers that show up used from time to time. A great place to start (and to finish!), but you might have to do some restoration work.
Avantgarde: Combines extremely deep bass with very high efficiency by using a powered woofer system. Not always easy to get a good blend between woofers and horns; easier on the larger models.
Cabasse: The very expensive “La Sphere” (that would be French for... “The Sphere”) sounded magnificent to me. Looks like a big beachball, or a giant eyeball. Not what one traditionally thinks of when talking about “high efficiency”, but worth mentioning in my opinion. Format is a four-way coaxial, with a 20" woofer centered behind the other drivers. On a weirdness scale of 1-10, it’s an 11.
Cain & Cain: Word class craftsmanship and very enjoyable sound in all of their models. Works of art that also make beautiful music. Single-driver based, sometimes with a supertweeter.
Classic Audio Reproductions: Superb dynamics and liveliness, and their Hartsfield is especially lifelike in dynamics though it doesn’t image very well. I would have become a C.A.R. dealer if they didn’t sell factory direct for what my cost would be.
Cogent: Extremely smooth and effortless. Very lifelike and maybe a bit on the warm side, which to me is a good thing. Perhaps the most lusted-after of high efficiency speakers, and certainly among the most mystical. I could listen to these all day long.
Duevel: Very wide sweet spot from unique omni-pattern horn.
Edgarhorn: Probably the standard by which other aspiring world-class high efficiency systems are judged. Very good to excellent across the board, superb bass, very relaxing long-term.
eXemplar: Very lively, lovely reproduction of cello, a bit weak in the bottom couple of octaves.
GedLee: Especially good at disappearing as the apparent sound source, very low in coloration, wide sweet spot. I sell these.
JBL: The discontinued model 4430 studio monitor is a classic and shows up used from time to time. The GedLees are a modern incarnation of the same basic concept.
Jumping Cactus: Very nice, primarily cone-based (four-way with horn tweeter) high efficiency system.
Klipsch: The Klipschorn and Belle Klipsch (the latter now discontinued) are very lively and enjoyable, though perhaps not as clean and uncolored as more modern designs.
Omega: Reasonably priced high quality single-driver speakers, typically a bit weak in the low bass. I sell these.
PHY: Makers of a high quality single-driver-ish (actually coaxial) speaker that has especially good bass extension for its type.
Pi Speakers: Available finished or as a parts-only kits. The 7Pi cornerhorn is particularly smooth and enjoyable. I’d pick it over the Klipschorn.
Rethm: The larger model is my favorite single-driver speaker sold in finished form. Very natural-sounding tone of voices and instruments.
Supravox: Now we have my favorite single driver that you have to build your own enclosure for, namely their 215-2000 EXC field coil driver. Superb imaging.
Tonian Labs: Importer of PHY drivers and maker of some very nice sounding, reasonably priced single driver and augmented single driver speakers.
Probably excellent but I haven’t heard ‘em: JBL K2 S9800, Kalinowski Custom Speakers, Pioneer TAD speaker systems (discontinued), Tannoy Westminster, Usher Audio D2.
Note that manufacturers Terry Cain, Steve Schell & Rich Drysdale (Cogent), Earl Geddes, and John Kalinowski (inmate “Kloss”) are regulars here at the Asylum.
No doubt I’ve left several worthy contenders off, but I’ve also intentionally omitted a few that I don’t think are especially worthy contenders.
As a (self-serving) aside, I build & sell an augmented single driver speaker (uses a supertweeter and built-in powered woofer). I’ll go out way on a limb here and claim that it doesn’t suck too bad.
Eso did a fine job of drawing the distinction between the two major types, and even-handedly commented on their relative merits. My preference is also for the multi-driver horn-based systems even though that’s not what I build... yet. Note that I haven’t consistently distinguished between fully horn-loaded systems and horn(s) on top/woofer on bottom systems, though that distinction is emphatically made by many. You’re more likely to get superb imaging and coherence from a single driver system, but it’s harder to get good tonal balance and deep bass out of them. And in dynamic capability the multi-driver horn-based systems have a huge advantage.
Finally, I’d like to toss out a bit of “minutia” that is near & dear to my heart. I place a very high priority on getting the reverberant field right, which calls for a uniform radiation pattern over as much of the spectrum as is practical. I believe this contributes to natural timbre, but won’t bore you with my reasoning. Just mentioning it as something you might want to keep in mind during your search.
Enjoy the journey, enjoy the discoveries, enjoy the company here!
Best of luck in your new quest,
Duke
