Some dynamic loudspeaker manufacturers consider the preservation of a music signal’s spectral coherency their top design priority, and often favors the 2-way approach. Although many manufacturers offer more than just the 2-way designs and companies producing strictly 2-way speakers are few, oftentimes these companies’ best efforts are their 2-way designs.
Then, there are those dynamic speaker makers that elect to pursue an even more purist venue in the form of crossover-less single-driver designs. Rethm of India is among the devout group of loudspeaker manufacturers that believes in the sonic realism such design will transpire even when compared to the best of the tweeter/woofer 2-way designs.
To Jacob George, Rethm’s proprietor, drivers developed from the latest technologies for reenacting credible engine roars and planetary annihilations have no business taking part in the consecrated music reproduction environment, and spectral coherency is just as important to him as tonal purity and single cone dispersions. At the end, expeditious transients and single-cone radiation are the absolutes in Mr. George’s mind for attaining natural dynamics and tonal coherency. To achieve his goals, Mr. George adopts Lowther’s 8-inch, neodymium magnet, paper cone DX4 driver.
Jacob George has definitive but realistic expectations in marrying his Rethm enclosure to the Lowther DX4, and in modifying the Lowther driver to his own specifications. The DX4’s original paper cone is proliferated by two inner layers of Rethm‘s own perforated paper cones, which in turn encircle a sizable, central wooden phase plug of Rethm’s design. The outer Rethm cone is attached to the driver’s diaphragm, while the inner perforated cone is attached to the phase plug, providing certain inertia for curtailing certain spectral anomalies. David Dicks of Lowther USA, in a 2-hour phone conversation with me, acknowledged that the DX4 is the most detailed, full-range Lowther driver ever designed for use in bass reflex enclosures.
The 2nd Rethm’s suggestive virtues are all readily visible. As Mr. George intended his loudspeakers to be rid of cabinet reflections and resonance, the molded plywood cabinet‘s front baffle is sculpted in a vertical cylinder extending all the way to the floor. At the top of this cylinder is a shorter, open cylinder flipped perpendicularly upward to house the Rethm-modified Lowther. With such construct and visual effects, my wife considers the 2nd Rethm the most visually appealing of all speakers in the house alongside the lacquered Madrone Audio Note AN-E SEC Silver.
Inside the top enclosure, the rear center of the Rethm-modified Lowther DX4 driver is encased in a molded foam to absorb out of phase higher frequencies. Lower frequencies emanating from the outer cone’s rear are allowed to double-back pass the damping foam and down a labyrinth for bass augmentation, diverting into two separate routes at a junction and eventually exiting through a port on the side of each of the two circular openings, one measuring 9.6 inches in diameter, and the other 11 inches.
A single-wiring terminal is located at the lower rear of each speaker, employing an industrial-grade, long durability plastic called Derlin, which accepts only 4-millimeter banana plugs and connects to the DX4 via a single 1-millimeter strand of bare copper wire. This practice of coupling a bare wire to a plastic medium was boldly pioneered by Japan’s 47 Laboratory in its 4708 OTA Cable Kit, in which a center plastic plug clipped with a copper wire is fitted through a matching plastic outer shell, wrapped in another wire of opposite polarity. By not passing the signal through metals and soldered joints in conventional terminals, designs from both Rethm and 47 Lab are said to deliver the least contaminated sound.
Positioning and System Compatibility
Mr. George set up his 2nd Rethm’s in my 12x27x8 listening room by situating them at a little over 7 feet apart phase plug to phase plug, 8 feet from the Lowther cones to the couch, and 7 ½ feet from the cones to the walls behind. Incidentally, Mr. George set up his speakers in a virtual equilibrium without using a measuring tape, and the height of the DX4’s were perfectly parallel to the ear at the listening position.
In my experimentation of positioning, I was able to induce the Rethm’s into performing the most convincing vanishing act of speakers, projecting a modest-width but most aerial and holographic soundstaging, by repositioning the speakers down to 6 feet apart and nearly a foot closer to the listening position.
Moving the speakers past that point towards the listening position diluted soundstage definition and accentuated an upper and lower midrange prominence, one that hovered around the upper range of electric guitar playing, as well as in clarinets and flutes. Repositioning the Rethm’s further against the front wall beyond Mr. George’s prescription only served to induce considerable degrees of the midrange excitability repeatedly. This excitability resurfaced when the speakers were toed-in as well.
Dispersion of the Rethm’s when faced straight out was extraordinarily wide, rendering the king’s sweet spot less of an issue, and facilitated a more liberal listening environment that encourages spousal participation. The Rethm-modified Lowther driver’s closer proximity to the listening area also minimized the room factor.
By my estimation, the 2nd Rethm had an in-room bottom-end response at around 60 to 80Hz, which my Genesis VI’s trio of active subwoofers were able to complement with their controller’s cutoff set to the lowest point of 70Hz. Conversely, the Genesis’ subwoofers represented a bittersweet engagement in consideration of the Rethm’s near-proximity, optimal placement to the listening position.
Within each of the Genesis 8-inch’s confinement, the 3 drivers operated in concordance to each other to deliver the most extended and fastest bottom-end; but the 42” tall, 11” wide and 18” deep Genesis VI mini towers dominated the center of the listening room alongside the 2nd Rethm’s in the optimal sonic integration. The effect was equivalent to having your own listening room shrunk considerably, which your wife would certainly object to. Most adamantly, too.
Relocating the Genesis’ to over 2 feet behind and to the side of the Rethm’s, in spots where they augment the Audio Note AN-E SEC Silver most effectively, the Rethm/Genesis engagement only served to produce detached, odd spectral spread. A minimal-profile subwoofer system comparable to the Genesis VI’s trio of 8-inch’s in flexibility, transient speed and power would be an ideal partner, although such a dream subwoofer system remains elusive in the marketplace.
The 2nd Rethm exhibited a predominant affinity towards finer digital front end and interconnects over other parts of the system.
Led by the 47 Laboratory 4704 PiTracer CD transport, Combak Corporation’s re-priced $4,400 Harmonix Reimyo 20bitK2 DAC, the DAP-777, made the Rethm’s more coherent than 47 Laboratory’s $7,100 4705-G Gemini Progression DAC, conceding only to the dual-mono 47 Lab’s dynamic and tonal contrasts. Then, Audio Note’s upgraded, $30k DAC 5 Special induced the Rethm’s to produce most vivid tonalities and wildest dynamics, with the most mesmerizing spatiality to boost. In conjunction with the DAC and amplification, AN’s Sogon digital and interconnects were essential in conveying advantages in equipment upstream.
On amplification, the Rethm’s were noisy at idling with most tube amplifiers, including Combak’s $36k Harmonix Reimyo CAT-777 and PAT-777 amplification, and the $6k pair of volume control-equipped Audion Silver Night Parallel Single-Ended monoblocks. Loth X’s $15k JI300 integrated 300B amplifier was the one remarkable exception whose quietness was on the par with Linn’s $9k Klimax Twin stereo power amplifier as driven by the Reference Line Preeminence Two Signature passive preamp, as well as 47 Laboratory’s $7,100 Gaincard S integrated.
Then, Audio Note’s $10k M5 preamplifier proved to be the quietest tube preamplifier thus far, as its pairing with the Linn KT in driving the Rethm produced faint idling noise that was audible only with 2 feet of the speakers.
In terms of sound, the Audion monoblocks were already capable of superlative dynamics when driving either the AN-E SEC Silver or Churchill Wideband, with a reserve that was apparently never called upon in driving the 100dB, crossover-less Rethm. For perspective, while the Audions’ volume pots were consistently at 20 to 30% of full volume when driving the Audio Note or the Tannoy, they never had to go beyond one-tenth of its full volume when driving the 2nd Rethm.
Next to the Harmonix Reimyo suite in tonal resolution, the Loth X JI300 surpassed all others in sheer musicality. Its Tokyo Ko-On broadcast-grade, stepped volume was even quieter than the 47 Lab’s DACT24 in operations, scoring a notable point with the crossover-less Lowther. Retrospectively, it was the Gaincard S that complemented the dimensionality of the Rethm most convincingly.
A big “little” surprise. I put Steve Deckert’s midget, $499, 5Wpc, volume control-equipped Decware SE84C to the test, and found the deprived-looking SET a transformed curiosity. The degree of dynamics and loudness the little Decware was able to induce from the Rethm elevated the little amp’s level of competence many times over. Steve was correct in his response to my March, 2002 Decware SE84C Review, that the crossover-less Lowther would be a better match for his little creation than my 104dB efficient, crossover-laden Klipschorn back then.
Doubly enticing was the fact that the Decware was just as quiet as the Loth X at idling. The SE84C remains a $499 item even to this day, so every tube aficionado could afford one. The suggestion of four Rethm’s and four SE84C’s in a home theatre system accelerates heartbeat.
Despite its noted, varying behaviors towards front ends and amplifications, the 2nd Rethm showed a curious insusceptibility towards the link between amplifiers and itself.
Experimentation with my cache of copper and silver speaker cables did not produce the differences in magnitude as did DACs. For instance, replacing my reference Audio Note SPx silver speaker cable with the company’s own large crystal copper AN-La rendered noticeable changes, but did not impact the Rethms’ tonality to the degree that would disqualify the copper AN, differing primarily in an improved top-end clarity in the SPx. Substituting the copper AN-La with the Tara Labs Phase II w/TFA Return yielded a similarly marginal inferiority, although in this case the advantage of the SPx became more obvious.
In the aforementioned phone conversation with Lowther Speaker USA, David Dicks further commented that because the DX4 was the most detailed Lowther driver ever, he normally would recommend the DX3 or DX2 in most cases, reserving the DX4 for customers with unusually absorptive, sonically dull rooms.
The dilemma of a speaker being capable of giving too much detailing had never happened to me, nor was I aware of speakers largely impervious to differences between AN’s copper and silver speaker cables.
Among other things, the perfect speaker cable would sense the impedance present at both of its ends proactively and calibrate its own property to complement the relationship. In the absence of such wonder cable, I am of the opinion that silver represents a superior medium for signal relay. Yet, the 2nd Rethm seemed insensible towards the advantage.
This experience recalls an encounter of another loudspeaker with a similar indifference at a dealership a few years ago, the owner of which tried to sell me a renowned British monitor on the premise that I could save on amplifier choices, as the 3 or 4 amps he rotated didn‘t make the speakers sound all that different.
In light of the Rethm’s changes in its interaction with all things else, it appears as if the Lowther harnesses a sensitive that lends less reliance on what comes between an amplifier and itself, which would explain its relative indifference towards advantages and characteristics silver cables have been effecting on speakers I’ve reviewed, such as the Audio Note AN-E SEC Silver, Tannoy Churchill Wideband, the Tannoy TD10, the ELAC CL330JET, etc.
Microdynamics and Dynamic Output
Since the 2nd Rethm’s dynamic profile benefited from the rather nearfield arrangement, which in turn enabled lower driver output in reaching higher perceived volume in my listening room, the resultant level of detail from lower midrange to the very top generated by the Rethm-modified 8-inch Lowther, regardless of amplification being used, was among the most abundant, approaching speakers in my household costing above $10k. Starting with extreme examples, the premonitory heavy metal world projected by James Hetfield and his Metallica band in the similarly-named 1991 release (Elektra 9 61113-2) sounded clearer and more spacious than most speakers I’ve used. Granted that instrument and soundstage delineations were not the priorities of the artists and producer, enough distinction came through that would change one’s preconception of the bombarding music. In rendering the sub-terrain region of “Enter the Sandman”, the Audion PSE monoblocks-driven 2nd Rethm fashioned a subjectively most conducive and full upper bass in the rendition of the rumbling bass guitar.
Recalling how my Genesis VI behaved as the primary speaker in reproducing the Metallica, with its active subwoofers exhibited spectacular excursions in throwing the bottom-ends at me, the Lowther DX4 surprised me with no cone movement at all, regardless of amplification being used with. Considering this is the CD bestowed with some of the most extreme bass lines, the fact that there was not a single sign of activity on the paper cone’s surface amidst the mayhem is simply beyond comprehension.
The one disc that is seemingly unsuitable for playing through the Rethm is JVC’s Dotou Banri XRCD by Ondekoza (JVC SVCD-1027) in its woofer-intended taiko drumming; but even so there were mitigating instances in which the Rethm cast its spell onto the listener, such as during the bamboo flute playing in “Yuki no Ashita”. Steered by the silent-running Loth X JI300 SET, the timbre detail of the lone instrument via the Rethm’s was among the most realistic I’ve experienced, and the speakers’ ability to cast the enormous taiko’s subdued rumbling in the background behind the flutist was simply first class.
The Rethm’s recreation of classical music also spotlighted a distinct design priority that favors sonority to scale. To illustrate, the violin solo in tone poem Also Sprach Zarathustra’s “The Dance-Song” (Deutsche Grammophon BMG D 13748) was rendered with an individuality sumptuously rich in flavor and texture. Yet, entire sections of strings and brass alike exhibited mild compression during the sunrise reenactment of the beginning track, and the music were not given the massiveness in scale that some minimonitors were able to produce, such as the Celestion SL700 and ELAC CL330JET.
If one were to contrast the 2nd Rethm’s dynamics aspect with drivers of similar size, such as the ELAC’s metal-impregnated 7-inch woofer and the Celestion’s 8-inch PVC woofer, which were conceived to break the bookshelf speakers’ barriers in reaching full-range status, then some readers might favor designs of the British and Germans’ instantly. For both ELAC and Celestion were of the metallic tweeter and high excursion woofer design, and their allegiance to a 2-way structure set well-established precedence in dynamics and outputs achievable in minimonitor. The 2nd Rethm, on the other hand, makes an indisputable testimonial in its superior dynamic transients, at
the expense of ultimate dynamic output.
Ideological boundaries and design tradeoffs seem to be realities that no loudspeaker manufacturer can underestimate.
On portrayal of piano solos, the 2nd Rethm provokes a most contentious predicament on its core existence.
Harvesting some of the most realistic piano sound in recent memories, RCA Red Seal’s 20-bit disc of Evgeny Kissin playing Chopin’s 24 Preludes (RCA 09026-63535-2, Chopin – 24 Preludes – Sonata No. 2 – Polonaise, Op. 53) yielded pristine top and bottom-end that overloaded the Audion-driven 2nd Rethm at high volume, resulting in occasional but noticeable lower midrange compression. Retrospectively, the Audion/Rethem’s piano playing from discs of relatively milder dynamics and softer transients, such as Arthur Rubinstein’s 1963 iteration of Beethoven’s Appassionata Sonata from the same label (RCA Red Seal 09026-63056-2, Beethoven Piano Sonata – Pathetique, Moonlight, Appassionata, Les Adieux) sounded markedly spotless, transcending and utterly rid of the shadow of a dynamically deprived sound.
Alternating amplification to 47 Lab’s Gaincard S ameliorated 2nd Rethm’s lower midrange shortfall completely in the Kissin disc without subduing the intrinsic dynamics: permeating throughout the 47 Lab-driven Rethm’s depiction of Rubinstein’s genius was a swift transient that exceeded what my Audio Note AN-E SEC Silver could approximate. It is noteworthy that accompanying the dandy little amp’s exceptionally excellent transients in the Rethm was an absence of the Audion’s midrange galore. Subjective tastes on the part of the listener will decide whether the 47 Lab or the Audion should be paired with the Rethm.
Not everybody listens to symphonies and classical music, and on that note, the Rethm was in top form when recreating jazz and pop concoctions. In fact, the most powerful testimonials to the Rethm method are its materialization of acoustic instruments, and First Impression Music’s hybrid SACD Autumn In Seattle (FIM SACD 040) represented the perfect musical genre to fulfilling the promise of the Rethm.
Via the Loth X JI300, the Rethm’s vanished in its rendition of the recording studio, an expanse that formed from behind one Rethm to the other, breathtakingly so in the hauntingly convincing dimensionality of each of the three players. The 2nd Rethm was able to resolve tonal contrasts of the piano, bass and drum given by the PiTracer/DAC 5 Special front end, and I was shocked at the lifelike transients liberated by the 8-inch Lowther. A world apart from the demands of large-scale symphonies, this jazz trio incursion was most inimitable towards substantiating the finesse of the 2nd Rethm.
Arguably a higher form of the Lowther method by virtue of the avant-garde cabinet conception and driver modification, the 2nd Rethm quickly reveals its virtues in continuous, daily interaction, revealing passage to a sonic reality that is apart from what we are familiar with.
It has an efficiency and crossover-less heart that makes it a true universal speaker, and it is utterly revelatory of differences in front ends and amplifications used. Readers using less exotic speaker cables can further be assured of a first-class experience.
When used with care and within the realm of its output level, the 2nd Rethm’s level of musicality is of exaltation. The sound of the 8-inch paper Lowther is surprisingly fast and spacious, its resolving prowess nurturing intrinsic sensibilities in all music that it graces. For the gentle souls among DAGOGO readers seeking musical enchantment, the 2nd Rethm is a most unique companion promising elation of a kind unheard of.
Jacob George’s novel adaptation of the Lowther DX4 and his thoroughly conceived enclosure set a new standard in the art of sound reproduction. In exploitation of the Lowther advantage, Mr George diverges from the bass reflex methods traversed by most Lowther adaptors, and embarked upon a Herculean effort in cabinet diffraction and resonance control. The resultant cylinder-based enclosure in molded plywood is beautiful beyond reproach, and makes a most profound statement among loudspeakers manufacturers. What if Jacob applies his talents into designing sports cars, too?
In retrospect, as fantastic as the Lowther paper cone is in all things mentioned, it is also the only speaker material I’ve encountered in that size that compresses lower midrange at progressively higher volumes, as well as becoming utterly deficient in reproduction of the lower registers. More ironic is the fact that even as the Lowther-equipped Rethm is the only loudspeaker I’ve encountered that the midget Decware could drive to high volumes, the Lowther would distort once driven past a volume threshold.
Therefore, although he bass augmentation strategy incorporated into the 2nd Rethm accorded the speaker articulate tonalities at its lowest point, it is not enough to accord the speaker a place in the full-range hall of fame by way of the paper Lowther.
DAGOGO readers who would scrutinize the 2nd Rethm as persistently and restlessly as I did are probably few, but I nonetheless take great comfort and a greater heed in realizing from email letters that DAGOGO’s readers are an examining bunch. So, allow me in offering the following closing words.
We, the audiophiles, are intrinsically more demanding, idealistic and stubborn than the secular music lover, and the extra dimension we seek in music appreciation puts us in a league of our own. Paralleling this shared passion of ours is the unique music preference each of us developed. With this in mind, here is my counsel: for any young and old DAGOGO reader who fantasizes for a peaceful and quiet retirement in the company of violin and wine in 50 years, and whose musical preference does not include the overwhelming recreation of a full orchestra and planetary destructions, treat yourselves to an early retirement of peace and love in a pair of the 2nd Rethm.
Digital Front End
47 Laboratory 4704 PiTracer CD transport
47 Laboratory 4705-G Gemini Progression DAC
Accustic Arts Player I Upsampling CD player
Audio Note DAC One 1.1x Signature
Audio Note DAC 5 Special
GW Labs DSP Engine
Harmonix Reimyo DAP-777 20bit K2 DAC
Sony SCD-777ES SACD/CD player
47 Laboratory 4706 dual mono Gaincard S with DACT24 & Cardas posts
Audion Golden Silver Night 300B monoblocks
GW Labs 270 tube power amplifier
Harmonix Reimyo CAT-777 preamplifier
Harmonix Reimyo PAT-777 300B stereo amplifier
Linn Klimax Twin
Loth X JI300 integrated amplifier
Reference Line Preeminence Two passive preamplifier
Reference Line Preeminence One Signature power amplifier]
Z-systems RDP-1 Reference Digital Preamplifier
47 Laboraotory 4722 Lens minimonitors
Apogee Duetta Signature
Audio Note AN-E SEC Silver
Murata ES105 spherical super tweeter
Tannoy Churchill Wideband
Tannoy Dimension TD10
Audio Note Sogon digital cable (1m, RCA)
Audio Note Sogon interconnect (2m pair, RCA)
Audio Note AN-Vx interconnect (1.5m, RCA)
Audio Note AN-V silver interconnect (RCA 1m, 2 pairs)
Audio Note AN-SPx speaker cable (2m, bananas, bi-wired)
Audio Note AN-La copper speaker cable (8 feet, bi-wired)
Canare L-5CFB 75-ohm digital cable (RCA, 1.5m)
Canare D206 110 ohm digital cable (AES/EBU, 1.5m)
Cardas Quadlink 5C (8 feet)
Granite Audio #470 silver cables (RCA 1m, 2 pairs)
Granite Audio #560 AC Mains (2)
Harmonix Reimyo Studio Master AC cord (2)
Illuminations D-60 75 Ohm digital cable (1.5m, RCA)
Van den Hul MCD-352 (8 feet)
ISO, Salamander Synergy 20 (2), ASC Tube Traps and Flat Traps
REVIEWS OF OTHER EQUIPMENT MENTIONED:
47 Laboratory 4704 PiTracer CD transport
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