Reviewer: Srajan Ebaen
Source: Cairn Fog v2.0 as transport; Zanden Audio Model 5000 MkIII DAC; Ortho Spectrum AR-2000 filter/buffer on the DAC's analog outputs; Eastern Electric MiniMax CDP [on review]
Preamp/Integrated: Bel Canto PRe2 GenII; Eastern Electric MiniMax [on loan]; Acoustic Reality eAR Pre2 [on review]; Antique Sound Lab MGHead DT/OTL 32 [on review]; Wyetech Labs Opal [on review]
Amp: AUDIOPAX Model 88; Bel Canto eVo 4 GenII; Eastern Electric MiniMax amplifier [on review]
Speakers: Avantgarde Acoustic DUO; nOrh SM 6.9, Gallo Acoustic Reference III
Cables: HMS Grand Finale; Analysis Plus Solo Oval and Oval 8; i2digital X-60 and Stereovox HDXV S/PDIF cables; Mapleshade Ebony active S/PDIF interconnect; Furutech Digi. Reference BNC-BNC digital cable; ma recordings BNC/BNC reference digital cable [on review]; Mapleshade Planar power cord with DC bias; Audio Magic Clairvoyant power cords; Crystal Cable Reference complete wire set of analog and digital interconnects, speaker cables and power cords; Z-Cable Reference Cyclone power cords on both powerline conditioner; 2 x Stealth Audio Cables Indra analogue &Varidig S/PDIF cable [on review]; Artistic Audio Vacuum Reference S/PDIF [on review]; Dynamic Design digital interconnects [on review]; Audience Au24 digital interconnect [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 squ.ft floor plan and significant 'active' cubic air volume of essentially the entire (small) house
Review component retail: $2,300

Impressions
Wyetech Labs' Canadian Roger Hebert strikes your writer as an engineer's engineer. There are certain tell-tale signs surrounding his products which prompt this reaction. For one, the documentation for every one of his tubed components -- preamps and power amps, on-line and owner's manual -- is so extensive as to leave no leaf unturned. Simply put, there are no 'proprietary' secrets. What makes these products special isn't some form of unobtainium parts or dark-ops circuits but superior implementation.


Expressions
For another, the appearance and feature set of Wyetech Labs gear is a fetching combination of retro and yeoman no-nonsense. The features provided and omitted are a thinking man's address about what you really need and what'll perform best. On his entry-level Coral preamplifier under review today, this means 4 line-level inputs, 1 tape loop, 1 fixed-gain output and two variable-gain pre outs; a high-quality resistor-ladder balance control with silver-plated contacts and 1dB increments over a range of +/-5dB; internal dual-mono jumpers for 4.5 and 12.5dB gain settings with 3.5 and 7.5Vrms outputs respectively; massive NKK toggle mute, power and tape monitor switches; clearly engraved front-panel attenuation settings for repeatability not just via dial markers but actual dB figures; a 90-second soft-start auto-mute to prevent turn-on thumps and prolong tube life; a resistor-ladder top-quality ELMA attenuator with 24 gold-plated contacts of 0.1% precision metal-film surface-mount resistors for channel accuracy of +/- 0.05dB; and an absolutely shocking frequency response of 4Hz to 825kHz +0/-3dB (referenced to a sine wave at 3.5Vrms output) which eludes most solid-state preamps, never mind tubed units.


Attention to detail is expressed with aluminum chassis panels and stainless steel screws for RFI rejection; dual hex screws affixing the control knobs to prevent shaft slippage; automotive high-gloss dark-lavender paint finish and polished brass handles; dual-layer hand-soldered glass epoxy circuit boards with bi-sided masking; Teflon-coated silver-plated OFHC copper hookup wiring; a two-pole relay for muting which isn't in the circuit path when disengaged; 27 WECO flying-lead screw connections to facilitate easy parts replacements; 18 gold-plated Teflon-insulated RCA terminals; and non-inverting absolute phase.


The low-noise, zero-feedback DC-coupled and mirror-imaged circuit is a three-stage grounded-grid topology with a pre/post cathode follower. It uses two 5814As and one 5687WB which are pre-installed NOS-JAN (joint Army/Navy) military issue from the company's own inventory which was assembled in sufficient quantities well prior to committing to the actual design. The power supply uses a toroidal Richard Sumner power transformer, a Pi RC filter for the 250-volt plate supply and a dual Pi RC filter on the 12-volt filament supply, with purely passive filter components to maintain the circuit's inherent speed. Physical dimensions of the Coral are 15" x 10.9" x 3.75" WxDxH and 12 lbs. The warranty is 1 year on the tubes and 5 years parts & labor with submitted registration.
The line-up of Wyetech Labs' preamps progresses, top down, from the Opal [$7,800/$204] to the Pearl [$5,300/$135], then the Jade [$3,800/$90-135] and finally today's Coral [$2,300/$48]. The second price figures are for matched replacement tube sets, respectively. It's fair to say that Roger covered his model bases rather comprehensively while deliberately electing to play in the sane rather than committed ranges of High-End audio's inflationary/bancrupt pricing scheme.


One feature I already noted as lacking on the Klimo Merlin valved preamplifier from Germany? Remote control. Dr. Klimo has since added this functionality to certain of his models, thereby invalidating the one 'modernity' complaint in my review. In the Coral's price range, this lack is less objectionable since a prospective buyer isn't acquiring an unconditional statement piece but rather one in which sonic performance, features and reliability are balanced to the best of its maker's ability. This naturally means eliminating remote if it can't be implemented both cost-effectively and without sonic compromise. By the time you part with $7,800 for Wyetech's best preamp effort, I'll leave it to you to determine whether this reasoning remains justifiable.

Even in its high-gain setting, the Coral via my 103dB Avantgardes was very quiet in the >28dB attenuation range I actually used to listen in. To truly maximize its theoretical noise floor, I did thereafter set it to lo-gain, however. The jumpers are clearly marked and change-over merely involved the loosening of 6 top-cover screws, pulling the jumpers and parking each with one leg reinserted into the pins. Low-gain in my circumstance did lower the noise floor even further and made things pop harder, suggestive of a higher contrast setting on video sources. Maxing out gain sans signal and in either setting did net power supply noise on my hornspeakers but that is to be expected. In the actual range used, the Coral proved dead-quiet.