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Reviewer:
Srajan Ebaen
Financial Interests: click here
Source:
27" iMac with 3.4GHz quad-core Intel Core i7, 16GB 1.333MHz RAM, 2TB hard disc, 256GB SSD drive, ADM Radeon HD 6970M with 2GB of GDDR5 memory, OSX 10.8.2, PureMusic 1.89g in hybrid memory play with pre-allocated RAM and AIFF files up to 24/192; Audirvana 1.5.5 in direct/integer mode 1, Metrum Acoustic Hex, AURALiC Vega
Preamp/Integrated:
Nagra Jazz, Esoteric C-03, Bent Audio Tap-X, TruLife Audio Athena, Bakoon AMP-12R
Amplifier
: First Watt SIT1, FirstWatt SIT2, Goldmund Job225, Crayon Audio CFA-1.2, AURALiC Merak monos [on loan]
Speakers:
soundkaos Wave 40, AudioSolutions Rhapsody 200, Boenicke Audio B10, Zu Audio Submission, German Physiks HRS-120, Davis Acoustics MV One [on review]
Cables: Complete loom of Zu Audio Event, KingRex uArt & Light Harmonic LightSpeed split USB cables, Tombo Trøn BNC/BNC S/PDIF, AudioQuest Diamond glass-fiber Toslink, Van den Hul AES/EBU
Stands:
Artesania Exoteryc double-wide 3-tier with TT glass shelf, Rajasthani solid hardwood console for amps
Powerline conditioning: GigaWatt PF2
with Vibex Two 1R on amps, Vibex Three 11R on front-end components
Sundry accessories: Extensive use of Acoustic System Resonators, noise filters and phase inverters
Room size: 5m x 11.5m W x D, 2.6m ceiling with exposed wooden cross beams every 60cm, plaster over brick walls, suspended wood floor with Tatami-type throw rugs. The listening space opens into the second storey via a staircase and the kitchen/dining room are behind the main listening chair. The latter is thus positioned in the middle of this open floor plan without the usual nearby back wall.
Review component retail: $20.000/pr [EL15m $15K/pr, EL60m $30K/pr]


The outback. For most of us in the Western hemisphere, Australia is one huge blank spot on the map. It's virtually on the opposite side of our world. Except for images of Sydney's famed opera and their equally picturesque Ayers Rock, there's precious little of concrete substance we associate. We know certain stats, say the spectacularly low population density outside the country's major cities. We've read of monster 15-axle tri-container lorries crisscrossing the continent on endless highways. We've read of Aborigines but never met one. We've heard of dingos and seen koalas and kangaroos in the zoo. We might have a few eucalyptus trees shed bark in our neck of the woods. We've admired the country's rolling hills of New South Wales with the talking pig of Babe. We were charmed by Crocodile Dundee. And that's about it.


With audio it's no better. How quickly can you rattle off just five domestic brands? Duntech goes way back. Later came Halcro, Continuum, Burson and Eichmann Technologies for a few who gained recognition abroad. In Edgar Kramer we have an Aussie contributor who also sits behind the editor's desk of Down Under's hifi print magazines. That's how our prior reviews of SGR Audio's EL30s amplifier and Signature rack came about. Revisit the first for its basic company profile and background on today's amp. When the time came to do a bit of gear sleuthing from my end because a number of promised deliveries were late, Edgar suggested their new EL30m monos. He had them in-house ready to depart. In a factory tour report of their Melbourne facilities published in last year's Audio Esoterica (a special annual print issue of Australian Hi-Fi dedicated to the best of high end for which he penned most reviews) our man expressed serious admiration for the scale and breadth of SGR Audio's vertically integrated operation and their overall ambitions.

The innards of the 160-watt stereo version in mirror-imaged layout

This includes numerous in-house CNC mills, wave-soldering stations, spray booths for automotive finishes, assembly areas, Finite Elemente analysis, CAD design, Clio speaker measurement software, Autodesk Inventor 3D modeling and a catalogue of three active speakers lines, amplifiers, an upscale rack and the perfectly monolithic MusicKube server with their very own software media player and MSB digital circuitry. Read his report of the visit here. In a subsequent email Edgar expressed equal admiration for the father and son principals of Harry and Stuart Ralston; and a non-partisan desire to see them gain traction and acclaim outside their large continent's watery borders. Hadn't heard yet of SGR Audio? That's my point.

A Google Earth view on the SGR Audio location


The EL30m is the mono version of the EL30s Edgar reviewed [see below with white Corian fascia]. A matching monaural twin exists for the EL15s. Finally there's the ultra EL60m which doubles today's 300w into 8Ω. At such stiff power ratings we obviously face class A/B. Here the first fistful of watts operate in pure class A. As the second photo above showed, all mono amps—and stereo for that matter—share a standard 340mm wide footprint. All are equally festooned with bristling heatsinks which by consuming half the real estate enforce vertical growth as power ratings scale up. SGR's signature ribs start out life as 4-meter long aluminium extrusions. In obvious celebration of machine-shop chops they recall the heydays of exuberantly styled heavy-metal muscle amps from Krell, Plinius and Threshold. [EL15s atop EL30s at left.]

The logo-duplicating but enlarged motif on the fascia operates as a defeatable VU meter. The Corian facia of the MkI amps is no longer available on the current MkII replacements.

As Jeff Rowland do for their 625 stereo amplifier, SGR drive their 12 x On Semi ThermalTrak bipolar transistors—I'd previously encountered those in ModWright's mighty KWA-150—with a National Semiconductor op-amp input buffer/driver stage. Inputs for the monos are on XLR exclusively with custom Jensen input transformers for galvanic isolation of signal ground. Circuitry is true balanced-differential for max common-mode noise rejection. A microprocessor controls signal-sensing auto on/off claimed to eliminate false triggers and cut-outs and also surveys power supply and thermal status. So-called stealth mode turns off all outer and inner LEDs for in-the-dark sonic immersion. 4-layer PCBs with field-cancelling topology use twice the industry-standard copper trace thickness.

The smaller EL15m brother.

The isolated ultra low-noise Plitron toroidal power supply with high-current 35A bridge rectifier lives on the 'dirty-room' ground floor topped by a 4mm steel plate to effectively shield the upper 'clean-room' circuit packed into the same half-width case. It uses gold-plated solid-copper buss bars and Linear Tech complementary regulators. Other pedigree parts are from Nichicon Muse, Wima, Vishay and Mills. Circuit gain is 28dB, bandwidth is 3Hz-50kHz -3dB. Idle power consumption is a low 20 watts, standby draws 5 watts.


SGR Audio amplification, Illuminator flagship speakers and rack with MSB digital front end and turntable. Bygone visions of Duntech or Dunlavy, anyone?