Product Review

Wyetech Labs Pearl Stereo Tube Line Stage Preamplifier

June, 2004

Jason Victor Serinus




● Tubes: Three 6SN7WGTA NOS Phillips Dual Triode

● MFR [ reference to a sine wave at 3.5 Vrms output ]
1. +/- 0 dB FLAT ... 15 Hz to 200 kHz
2. +0 dB/-1 dB ... 7 Hz to 520 kHz
3. +0 dB/-3 dB ... 3 Hz to 950 kHz

● Absolute Phase: Non-Inverting

● Input Impedance: 50 kOhms

● Output Impedance: 600 Ohms

● Rated Output: 3.5 Volts RMS

● Slew Rate: 25 µvolts/microsecond

● Dimensions: 4 1/4" H x 17" W x 14 1/4" D

● Weight: 18 Pounds

● MSRP: $5,300 USA

Wyetech Laboratories


Early in 2004, we published a review of Wyetech's $2300 Coral line stage preamplifier. My enjoyment of that entry-level preamp led me to salivate at thoughts of reviewing the flagship of Wyetech preamplifiers, the $7800 Opal.

However, given that the Opal has already received extended praise from the audiophile press, Wyetech's Roger Hebert suggested that I instead review the preamp closest to it, the $5300 Pearl line stage. The one-box Pearl has been designed to duplicate as close as possible the sound of the two-box Opal.

Both products employ the grounded grid configuration which Wyetech considers the best possible circuit topology for line level amplification. They also use the same circuit boards and Shallco switches. For a complete parts comparison chart, see


The Pearl offers four line level inputs plus a tape input. There is one tape output and one line level output. The Pearl only accepts cables with RCA (single-ended) termination (no XLR).

Taking a giant step away from the standard black and silver profile of most audio gear, the Pearl sports the Opal's shiny automotive finish gray face and oversized gold-plated brass control knobs. Red (mute) and green (ready) indicator lights are large and easily seen across the room. So are the silver tape/source and mute/on switches. There is no way this unit could be confused with another component on your rack.

Given that Wyetech supplies much technical information on its website, I shall simply comment that the volume control is unusually silent, offering 24 increments small enough to enable an adequate range of adjustment. I found the preamp a snap to install, connect, and power up.


At a recent meeting of the Bay Area Audiophile Society, several members bragged that they could tell the sound of a component lickety-split. “In Two seconds” was one boastful listener's claim.

Not me. I can certainly tell something about a component from a quick listen. But since different musical selections, genres, recording engineers, venues, and electronics bring to the fore different musical and sonic qualities, I prefer to contain my conclusions until after I've played a wide assortment of recordings that emphasize different aspects of the audiophile experience.

After isolating the Pearl from vibration by means of Gaymede feet, cleaning all connections, demagnetizing the system, and playing non-stop break-in tones for over 24 hours, I felt ready to take a first listen. I had the advantage of just having just auditioned the Manley 300B preamp, and thus having everything but the Pearl already in place.

My initial reaction to the Pearl mirrors what I felt when I first heard the Opal. What a beautiful sound this line stage has.

There are of course major differences between the Pearl and Opal. Because the Pearl employs higher quality parts, it is far more transparent, extended, and capable of greater dynamic range. But the two units definitely share a trademark warm, silken sound.

I may be a classical man at heart, but I've been spending more and more time exploring and loving world music. Thus, the first disc I played was not Brahms, but Zion Roots' Abyssinian Infinite featuring the arresting voice of Gigi Shibabaw. The sound was sweeter than I am accustomed to hearing through my Theta Gen. VIII. But it was so smooth, transparent, and beautiful that I didn't care. “Sound is smooth as a baby's skin” is what I wrote on my notes. This is a preamp that caresses you with its presentation.

That caress went deeper when I turned to the voice of the great Rosa Passos, paired with the bass of Ron Carter and guitar and percussion from other superb jazz musicians on Chesky's excellently recorded Entre Amigos. Passos seemed to sing with an almost forbidding intimacy, as though she was whispering to us. There was a sensual cuddliness to her voice, of the kind that makes you want to curl up and purr in her lap. I could not recall ever having felt such a seductively warm glow from her artistry.

When I turned to my old standby, Terry Evans' “Blues No More” track from Puttin' It Down (JVC-XRCD), I was neither expecting nor wanting a seductive, warm glow. That's not what this performance is about. Instead, I looked for an electric snap to the drums, a blues-tinged soul of an occasionally hoase voice, and a sizzle to the muted but nonetheless alive cymbals. These were not so readily in evidence.

Instead, I found a presentation so pleasingly palatable that I could not sense its ultimate blues bite. The twangy, slightly acid sound of Ry Cooder's electric guitar was unquestionably softened. It was as though I was gazing at Greta Garbo's visage through the scrim employed by George Cukor during the filming of Camille. Not a wrinkle in sight. Everything had a seductive softness. That may work for Garbo, but it's surely something I wasn't looking for in hard-edged blues, let alone the heavy metal mayhem of die-hard rock that causes my plants to grow in the opposite direction.

What, I wondered, would another cherished standby, Reference Recordings' Rachmaninoff Symphonic Dances, sound like? The initial size of the soundstage and resonant glow of the hall amazed me. So did the sheer beauty of the sound. Nonetheless, I wished for more bite. The low “thump thump thump” of the double basses seemed milder than usual. No, they weren't weaker or less full, but their visceral impact was softer due to the diffused nature of the Pearl's sound. I also noted that pitches were a bit less distinct.

This led me wonder what the Pearl would do with the voice of Maria Callas in her prime. EMI's remastering of Callas' mid-1950s performance of “La mamma morta” from Andrea Chenier (the same performance Tom Hanks listened to in the movie Philadelphia, albeit now in significantly improved sound) may at first seem a strange choice for an audiophile audition. After all, the sound is monaural and hardly state-of-art, what with the tape hiss, flatness, and general lack of silence that characterize Callas' earlier commercial recordings.

But Callas is Callas. There's no other soprano voice that comes close to conveying the Callas combination of fear-inflicting strength, heart-tugging fragility, untamed rage, smoothness of coloratura, and (in the higher reaches) steely attack. And it is the mono recordings Callas made in her prime that most fully display her unforgettable technical and emotional impact.

Welcome to a sweeter, gentler Callas. What a pretty, even beautiful voice the Pearl conveys. It's lovely, touching, inviting of repeated listening. But is it truly Callas? Someone coming to Callas for the first time via the Pearl would have a hard time understanding why some people claim that she " . . . has the voice of a bitch on wheels."

For a reality check, I returned to the Theta. Frankly, I could just as easily have popped the disc into David's antiquated sound system, or plugged my ancient portable CD player into the tape slot of my 1994 Toyota Corolla's standard radio. All three convey the little acid kick in the Callas voice that I am accustomed to hearing. The Theta's ultimate transparency also brings Callas a little closer to me, increasing the heart-tugging pull of her complex voice.

Preamp and Amp Hopping

Happily, the Manley 300B, which retails for virtually the same price as the Pearl, was still on hand. Again, I was sure to the warm the unit up, as well as demagnetize and break-in before proceeding.

Let's cut to the chase. On the Rachmaninoff, the Manley definitely offered more bite on high frequencies. It was less sweet than the Pearl and thus closer to the Theta's neutrality. Very low pitches also seemed a bit more distinct. Nonetheless, the top seemed to gradually roll off above 10K, resulting in a less extended presentation than with the Theta, and ultimate bass extension and control were wanting.

The Manley 300B was a different sound, to be sure. As to which one an audiophile might prefer, it is simply a matter of taste and aesthetics.

What, I wondered, would both preamps sound like when paired, not with the tubed Jadis Defy 7, but with the recently reviewed solid state Soaring Audio SLC-300? This is an excellent amp for the price, especially notable for its midrange fullness and bass impact.

The most telling comparison again occurred with the Callas. The Manley lent a warmer glow to Callas' voice than I was accustomed to hearing. The voice was a little fuzzy on top, and a bit of the edge was gone. But it was still recognizably Callas.

With the Pearl, we were introduced to a gentler, kinder Callas. The sonic presentation was far more silent as well. It was as though Callas had stepped off the stage and changed out of her costume. Here she was entertaining fans and reporters after a triumphant performance, dressed in one of the many strings of pearls she so admired. Kind, gentle, demure, even shy, this was the face of Callas she sometimes assumed when someone like Edward R. Murrow didn't turn in the screws and force her to account for her string of scandals and vocal mishaps.

To come full circle, I mated the Soaring Audio with the Theta Gen VIII. The thing that shocked me most was the amount of background studio noise I again heard on the mono recording that I had not heard through the Pearl. Clearly the Pearl is one forgiving preamp. I also heard more overtones on the cello that figures prominently in the aria's orchestral introduction, and more coldness and hollowness to Callas' voice.


Reviewing equipment is a bit like analyzing politics. There's a tendency to polarize, to say this is good and that's bad. But life is not that simple.

Will the real post-Hussein Iraq please stand up? Shall we order from Column A or Column B? What do we want to see? What do we want to hear?

For many listeners, the Pearl preamp presents an ideal vehicle for listening. Its forgiving, soft, somewhat rose-colored glasses gaze into the heart of the musical experience delivers precisely the pleasant listening that so many of us seek.

The Pearl has an almost magical intimacy, a silken seductiveness that's hard to resist. The sound is so lovely and beautiful, it's almost hypnotic. If this is what you value most from a high-end audio system, by all means take advantage of Wyetech's 30-day trial and give the Pearl a listen. Unless you're looking for the sonic equivalent of horseradish, you are sure to find much to admire.

- Jason Victor Serinus -

Associated Equipment:

Digital Front End
Sony 707ES transport modified by Alexander Peychev of APL Hi-Fi
Theta Gen VIII

Perpetual Technologies P-1A with modified Monolithic Power Supply and Revelation Audio umbilical power cable (not used for this review)

Jadis Defy 7 Mk IV modified with a Siltech silver harness

Bruce Moore Companion III tube preamp with Electro-Harmonix gold pin 6922s and Jan Philips 12AU7 equivalents;
Reflection Audio OM-1 Quantum battery-powered preamp in non-battery mode (used for this review)

Talon Khorus X speakers (with latest modifications and Bybee filters that render its response even across the spectrum and greatly improve the bass)

Nordost Valhalla interconnects and digital interconnects
Nordost Valhalla bi-wired speaker cable
Powercables: Elrod EPS-1, 2, and 3 and EPS-2 and -3 Signature on main chain plus Harmonic Tech, Nordost, and AudioPrism SuperNatural S2 elsewhere

PS Audio P600 Power Plant power synthesizer with MultiWave II
PS Audio Ultimate Outlet; PS Audio Power Ports
Michael Green Deluxe Ultrarack, Basic Racks, room treatment, and Audiopoints
Ganymede supports under amp and transport
Black Diamond Racing Cones
Shakti stones on Amp, Monolithic/P-1A and Theta
Bedini Quadra Beam Ultraclarifier
Audioprism Stoplight and latest, Marigo Stealth Mat for CDs
Sheffield/XLO degmagnetiser and break-in disc and Ayre demagnetizing disc

© Copyright 2004 Secrets of Home Theater & High Fidelity

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