High sensitivity done right
$54,175 – $57,465/pair (finish dependent)
supremeacousticsystems.com (US distributor)
odeon-audio.com (factory)
As with so many reviews, this one begins with Aimee Mann’s “Humpty Dumpty” to anchor things. I’m immediately taken by the way Mann’s vocals anchor somewhat to the right of the sound field these moderately sized speakers create, powered by the exquisite AirTight ATM-300B amplifier, driven directly by the Wavedream DAC. Sporting a sensitivity spec of 96dB/1-watt, the luscious Air Tight amplifier never strains in the least, powering these speakers in SAS’s large demo room. There’s nothing like big speakers in a big room to create lifelike sonic cues.
The two-piece Sempers weigh 185 pounds assembled. With shipping being what it is these days and the risk that these exquisitely finished speakers could be damaged in transit, it makes more sense to jump on the 1:45 flight to Las Vegas and pay Supreme Acoustic Systems a visit. I’ve spent enough time at SAS over the last year to become more than familiar with their setups, and insisting that “the speakers must be in my room” is a waste of efficiency. And hey, not having to move big speakers is an added bonus. #askmehowiknow.
I’ve got a big-ish room at 24 x 36, but SAS has a really big room at 36 x 54 feet. Incredible! Yet with the big YGs and a few other speakers, it’s the way to experience big sound. The Odeon Sempers sit in one system, along with the larger flagship Carnegie to compare. Much like planar speakers, larger horn speakers are built for larger rooms. If you have a medium to large room, the Semper will probably be a better match than the Carnegie, because it’s about properly pressurizing the room and getting back far enough for the drivers to integrate. Horn speakers often get a bad rap because they are in rooms that are too small to let them do their thing.
Setup
Fortunately, the Sempers are set up when I arrive, so I don’t have to go through the painstaking part of dialing in a pair of 185-pound speakers. SAS’s principal, Hiram Toro, assures me that these speakers set up pretty quickly. They are set up to perfection in his space. The photo below, shows them in their approximate location, with different gear between the speakers. (and woofer grilles affixed)
With the speakers about 12 feet apart and about 6 feet from the rear wall in Hiram Toro’s massive listening room, the optimum listening position is about 10 feet back from the speakers. Moving closer in delivers a more intimate, almost headphone-like vibe, while moving back a few feet beyond the 10-foot spot makes the presentation more diffuse (and less pinpoint-like) but equally compelling. If you have the luxury of space in your room, you’ll find that perfect spot that provides the best balance of explosive dynamics and a sound field that’s just the right size for your taste. And you might just find that mixing it up with different music is more fun.
Seriously, if you can set your Odeons up in a larger room, the ability to adjust perspective to your taste and the music playing is a major benefit.
Odeon claims a frequency response of 28 – 28,000 Hz, and while we had no test instruments handy, calling up some test tones on Qobuz confirms solid bass down to 30 Hz, with 20 Hz falling off. Hey, if you’ve got a room big enough for these, you might even add a pair of subs – or six, but that’s another movie.
Not all high-sensitivity speakers are created equal. Some use overly complex crossover networks that tend to eat up the first watt (the most important one) and can sound less than lively or require more power than you might suspect. The Sempers present an easy load for the Air Tight 300B amplifier (one of the wonders of the audio world) and achieve a volume level that most of us will never need to play music loudly.
That said, the true magic of what these speakers deliver is at a modest, almost conversational level. There’s a level of transparency here that rivals the best panels, combined with realistic dynamics that always breathe more life into the music, no matter the genre.
Considering the very reasonable cost of the Air Tight (about $20k) or your favorite SET, source(s), and cables, this makes for a total system cost of about $100k. The level of musical realism this delivers is tough to beat.
Truly, the only aspect of these speakers I did not get to experience in the same way I would in the TONE studio is using a wide range of amplifiers. We did, however, switch from the 300B amplifier to another AirTight amplifier, the ATM-2Plus, powered by KT88 tubes. Things got even more dynamic, but slightly less extreme fine detail. Still lovely, but the mega resolution that these speakers produce will offer the end user an interesting experience to find their perfect amplifier.
Construction
The Sempers are unique because they use a down-firing ported design for the woofer, which is a 13” Audax driver with a lightweight paper cone. A similar but smaller design than the 15-inch driver used in their top Carnegie. This downward-firing port makes the Semper much easier to place in a room than a speaker system with front- or rear-firing ports.
No attention to detail in the hand-assembled, point-to-point wired crossover networks, featuring the highest-quality premium parts with 1% tolerance. The cabinetry is achieved with a similar design aesthetic. This level of attention to every aspect of the Semper’s execution is a big part of their cost. The other is the level of musical realism they achieve.
The horn/waveguides that couple the midrange and tweeter are works of art, and help to deliver image focus, so form does follow function here.
More listening
The Sempers deliver dynamics in a quick, responsive, articulate way that makes even listening at low volume immersive. They go beyond delivering precise imaging, creating a sense of realistic scale that brings you closer to the illusion of having musicians in your room than a box speaker usually can. If you’ve spent time in front of a pair of big-ish Wilson, Magico, Rockport, or other top-line speakers, you know they can deliver “pinpoint imaging” (if they are set up correctly), but what the Semper brings to the presentation is different. Some call it a jump factor, but it’s more than that.
Moving on to Jean-Michel Jarre’s “Ethnicolor” (from Zoolook) confirms the initial excitement over the envelopment that these horn speakers provide. The additional clarity that the Odeons offer, combined with their massive dynamic range, pulls you in.
Mixing it up with some Crash Test Dummies – “Superman’s Song” and “Just Chillin” makes for more envelopment. As someone with an admitted bias for big panels, the top-to-bottom integration of the 13” woofer, horn-loaded midrange, and horn-loaded tweeter is exquisite. Few cone speakers at any price achieve this level of performance.
The Sempers exhibit none of the squawking, beaming that befalls other horn designs, and they have a wide enough dispersion that they still sound great, even way off the axis of the sweet spot, sitting on the floor. This is significant because, should you have several people over to listen to music, everyone can have a good time with the Sempers. Not just the one person sitting in “the spot.” This speaker goes beyond audiophile performance and engages.
Exploring the extremes
Grooving on Squeeze’s 1995 record Ridiculous, the vocals in “Long Face” sound almost Tom Waits-like. #nobigjohnhere. Glorious. By now, the WE 300Bs in the Air Tight amp have been on for hours, and the front-to-back image of the massively layered vocals all have distinct, locked-in spots. Every one of the well-worn tracks picked reveals texture and detail galore.
The Semper’s biggest beauty is its ability to play well at a modest volume. When called upon to recreate the drama of a live performance, they do so effortlessly. Even listening at an approachable level around 75dB, with 80-something dB peaks, it feels loud.
When you need to rock, they do that too. There’s just something incredible about listening to a live performance on a great pair of horn speakers. Turning the volume up to enjoy “Because We’ve Ended as Lovers” from Jeff Beck’s Live at Ronnie Scott’s, rockets between silent and stupendously loud passages, and he wrings the notes from his Stratocaster with his band.
Tonally, and as you might suspect, the Sempers give you a more forward, front-five-rows look into the music, which I find exciting. Where my Clarisys Auditorium/REL 6-pack reference system has more of a 12th-row perspective, and the Magnepans feel another 10 or 15 rows back, the Sempers are up front and engaging.
By comparison, the same tracks on my reference Klipschorns are very different. The big K horn is not as refined in terms of minute detail and image precision. And the Sempers go deeper, as they should, for 2.5x the price.
It keeps coming back to texture
There’s nothing about the Sempers I don’t love. Yet their ability to pull the tiniest of details from familiar recordings without sounding strident, harsh, or exaggerated borders on magic. Isn’t that what being engaged by music is all about? It’s so easy to forget about the system with these speakers.
Along with the massive amount of detail served up, the Sempers image like crazy. Running through Mickey Hart’s At The Edge is truly psychedelic. What would you expect from the Dead’s percussionist? The big drums hit hard, with gentle, rolling synths in the mix, all wrapped up with bits of rare percussion and cymbals floating around the landscape. This record actually sounds more inviting with the listening chair back further.
The Semper delivers a maximum amount of musical information without deconstructing it. This is a weakness that speakers focused merely on delivering a pinpoint image as the audio grail, lose the pace of the music.
These speakers are so engaging that a 5-minute break for a quick slice of pizza is the only distraction I afford myself, and before I know it, a nine-hour day in front of the Sempers is done, and it’s time to head back home. I feel like my bull terrier after playing with puzzles all day – exhausted but happy.
If you have enough room to make a pair of these breathe, you owe it to yourself to experience a pair. If you’ve never considered a pair of horns or perhaps had a pre-conceived notion of what you thought the horn experience was, the Odeon Semper might avail you to an entirely new audio experience.
A week later, watching Aimee Mann perform Lost in Space in its entirety in a modest-sized hall, the sheer spaciousness that these speakers deliver confirms their excellence.
Even as a horn enthusiast, they have established a new paradigm for me. Highly recommended. -Jeff Dorgay
