Reviewer: Srajan Ebaen
Source: Cairn Fog v2.0 as transport; Zanden Audio Model 5000 MkIII DAC; Furutech Digi. Reference BNC-BNC digital cable; Ortho Spectrum AR-2000 filter/buffer on the DAC's analog outputs
Preamp/Integrated: Bel Canto PRe6
Amp: AUDIOPAX Model 88; Coda Technologies S5 [on review]; Acoustic Reality Enigma Plus [on review]
Speakers: Avantgarde Acoustic DUO
Cables: HMS Grand Finale; Analysis Plus Solo Oval and Oval 8; i2digital X-60; Stereovox HDXV; Mapleshade Ebony active digital interconnect; Mapleshade Planar power cord with DC bias; Audio Magic Clairvoyant power cords; Z-Cable Reference cables and Hurricane power cords [on review]
Stands: Grand Prix Audio Monaco four-tier
Powerline conditioning: BPT BP-3.5 Signature; Walker Audio Velocitor for source components
Sundry accessories: GPA Formula Carbon/Kevlar shelf for tube amps; GPA Apex footers underneath stand and speakers; Walker Audio SST on all connections; Walker Audio Vivid CD cleaner; Furutech RD-2 CD demagnetizer; WorldPower cryo'd Hubbell wall sockets; Musse Audio resonance dampers on DUO subs; Mapleshade 4" solid maple platform under BPT conditioner
Room size: 30' w x 18' d x 10' h [sloping ceiling] in long-wall setup in one half, with open adjoining living room for a total of ca.1000 sft floorplan and significant 'active' cubic air volume of essentially entire house
Review component retail: $6,480/pr

Lowthers. Mention them to the utterly uninitiated audiophile bystander. Chances are, you'll hear "Lowther shout" in response. This demonstrates that the Achilles heel of these full-range drivers is far more infamous than their many virtues. And that's true regardless over whether such opinionates have ever even heard a Lowther-based speaker in the flesh. Being mostly known for one's shortcomings by repute and from the distance makes not only for one massively foregone conclusion. It also erects a perception barrier that anyone working with these devices in production loudspeakers must tackle. Put more succinctly, you're liably written off before you ever got a chance to make your point. That would be too bad.

Jacob George of Rethm is the first to agree that yes, unmodified and simply stuck into any old cabinet, Lowthers
do suffer from an upper midrange peakiness that veritably honks at the listener. He would further admit that to get decent bass performance from these drivers poses real engineering challenges in the driver loading department. Which raises the obvious question: If both bystanders and intimates agree that these drivers have problems, why even bother? The answer boils down to the promise of zero-crossover, zero phase-shift, zero time-delay, zero-lobing coherence. The whole single-driver ideal is to loudspeaker designers what a zero NFB single-ended triode is to amplifier builders - minimum mechanical and electrical complexity to pass the fragile and complex music signal fully intact. More importantly, to pass it in one piece that doesn't require reassembly in the listener's ear/brain apparatus: Speaking with one single voice rather than many (forked tongue, anybody?). Immediacy. Directness. Clarity. Transparency. These are the bewitching qualities that compel designers like Jacob to brave the many obstacles of fabricating commercially successful single-driver Lowther models.

But nobody said that was easy. A single glance at Jacob's The Second -- incidentally his first-ever design -- immediately telegraphs unconventionality, something borne from years of architectural training and practice (including four years at the Brooklyn School of Architecture/Pratt Institute); his gift for thinking outside of the box; and a concise aural image of his ideal which is firmly imprinted in his mind. While you're still close to the photo above, focus on the far speaker. Imagine yourself as the driver rear wave. Travel back from the DX-4 Lowther through a gradually expanding, formed plywood (not PVC!) tube of semi-spherical profile. Stay horizontal, then follow the downward slope of the cabinet above the two holes. Go vertical toward the floor past the big hole, hang a right angle to now move underneath it and return to the cabinet's front. Then hang another 90-degree turn to go straight up until you reach the bottom of the driver. Now turn back again for your first 360-degree loop of continuously expanding and widening tunnel fun. Commence downward again (just below your first passage this time) until you come to a fork in the road: A smaller portion of you-as-the-rearwave will exit through an opening inside the upper hole, the far larger portion of you will travel a bit farther to exit through a similar opening in the larger hole.

But that's not all. In order to prevent this rear wave from reflecting off the first change-of-direction barrier back through the diaphragm -- a major flaw of most Lowther-based designs according to Jacob -- our clever engineer affixes a rather sizable expanded polystyrene attachment to the driver magnet to create a compression chamber that effectively prevents both back flow and accelerates the rear wave to commence its hasty progress through the circular rear-horn/TL-hybrid labyrinth.

Are you pro birth control but no elephant? Join the club, enjoy a moment of levity and then move past the predictable locker room jokes. Jacob rather unceremoniously wrapped a stretch of black electrican's tape around the juncture of magnet and cone rim, then attached his 1mm solid-core copper leads in linen sheathing to the Lowther terminals and mounted the driver to the tube rim with four special screws.

The next operation involved more screwing, this time by way of his - okay, wooden phase plug whose perforated skirt pattern, size and angle was the result of 4 months worth of testing.

So while -- and because -- there's only one driver to go around in this design, the transducer itself and what happens behind and around it become hyper critical. The final coup-de-grace is the radiused trim/dispersion ring that hides the driver basket flanges as well as provide an edge-free contour to minimize off-axis turbulences, reflections and refractions.

Three further steps of partial assembly were required before the curved-bottom Rethm would stably greet the flatness of Mother Earth - attachment of the winged brackets which, between each other, wedge the central metal rail into place.

The second image in the assembly trio of pix to the right shows said rail. It makes two lone points of contact with the bottom section of the actual tube - front and aft via set screws that double on their lower ends as additional floor couplers. In addition to the four spikes of the wings, this gives 6 points of floor coupling, the rearward one necessary for balance since the speaker itself is 34 inches deep whereas the base formed by the wings only accounts for 14.5".

The front and back set screws should be adjusted to touch the beast's belly and act as vibrational pathways between cabinet proper and floor. The clamshell arrangement of the wing attachment otherwise creates more decoupling and floating than coupling.

All in all, a most fascinating contraption that combines complicated internals -- which create two vents with different preceding path lengths, one of 9ft 6in. and one of 11ft from the driver -- with extensive front/aft driver modifications. The former add a proprietary wooden phase plug with its own stationary skirt to a second skirt of different perf patterning which is affixed to the driver proper and hence moves with its excursions and rarefactions. These frontal add-ons are unique to Rethm and tailor frequency response to mitigate the famous Lowther peak.

The compression chamber formed between the attachment and the surrounding tunnel walls eliminates back flow and thus driver colorations, while the subsequent spiral "transmission line" prevents internal standing waves and concomitant "box talk". It takes no genius to appreciate that Jacob George skinned his Lowther cat in a very novel, thoroughly thru-engineered and brilliant fashion.

The true genius part enters the picture when you consider that all this novelty found itself already incorporated into the very first Rethm model Jacob ever designed. Admittedly, the Second has benefitted from certain evolutionary refinements since its launch in 2000, but the basic architecture already appeared in the debut version. Possibly more stunning yet -- at least if you've been in speaker manufacture before to appreciate the 1001 reasons why you should not attempt cabinets with compound angles, non-parallel-wall bending tunnels and curved surfaces -- is the physical construction; the fact that its country of origin is India; and that the final product looks visually stunning, finished, modern and architectural. There really hasn't been anything quite like it before. And for $6,480/pr retail, you couldn't begin to dream of building the Second Rethm with formed plywood sub-assemblies in the gool ol' US of A.

India. Besides residential and commercial architecture, Jacob also designs and builds furniture. His woodworkers fashion both Rethm speakers and furniture depending on whatever orders happen to be pinned to that week's schedule. Because Jacob grew up in Singapore and spent many formative years in the US, his standards for fit'n'finish as well as overall appearance have undergone thorough "Westernization". All of these ingredients begin to explain Rethm but fail to tell the whole story. As Jacob shared, India is a vital part of the recipe not just because of lower labor rates. To the enterprising architect, Indian legislature doesn't impose the constructional code limitations of the West. If you can envision and draw it, you can build it. This artistic and conceptual freedom welcomes and stimulates unconventional thinking. It quite literally proved the necessary fertile context in which Jacob could look at speaker design from an untried "outsider's" perspective and conceive of everything that makes the Rethm The Second so fascinatingly different.

Perfecting assembly protocol and training a work crew unfamiliar with Western-style HighEnd audio how to manufacture with consistency and to flawless standards must have been its own -- and likely remains an ongoing -- challenge. Add the limited market for single-driver speakers; the limited visibility of an Indian manufacturer in the West where most such sales are conducted - and what makes Rethm unique just compounded well beyond the speaker model under review today.

Alas, my upcoming vacation in four days now limits what else you're going to learn until I return. Consider this a cliffhanger preview then, of very exciting things to come in late March, early April. I shall add this, however, to tempt you yet further. Those who have followed my HE2003, VSAC 2003 and CES 2004 reports will know how impressed I was with the Rethm showings at each of these events. Needless to say, even the most favorable of show conditions -- or the cleverest of exploitations of truly ruinous ones, which is probably far closer to the truth -- can't predict a product's performance within your own known four walls and with familiar ancillaries.

I'm gratified to report that shy of the last 10 Hertz of possible bass extension and the last word in soundstage depth (the former as a function of unpredictable room interaction; the latter because my long-wall setup doesn't allow for Jacob's favored mid-room center line placement) these Rethms duplicate the peculiar magic I had heard at three different shows now in my own environment - and with serious aplomb. My AUDIOPAX Model 88s prove to be extremely copasetic mates and I look forward to reporting to you in-depth about my musical encounters with these holey Indian creations.