Authorized Re-publication of Review from:

  The Inner Ear , Volume 16, # 4 2005
85 Moorehouse Drive, Scarborough, Ontario
Canada M1V 2E2
Tel: (416) 297-7968
Fax: (416) 297-0311
E-mail: editor@innerear.com
Website: www.innerear.com

 

WYETECH LABS PEARL Vacuum Tube Preamplifier

Source: Wyetech Labs

Price: $ 6300

Rating:

 

This company doesn't need much of an introduction as we have been using its top-of-the-line preamplifier - the model Opal ( reviewed in Vol. 10 # 2 ) - for our listening test for many years. Principal designer and head honcho Roger Hebert, has been around the electronics industry for about 10 years. The company is small by choice as Hebert believes in hands-on quality control of each carefully assembled component. The painstaking process of thoroughly checking and matching parts to very tight tolerances is - in Hebert's opinion - a labour of love. We see it, however, as one man's preoccupation with perfection - something we'd like to see more of when it comes to high end audio components, for it guarantees longevity and reliability.

Appearance:

As with all Wyetech Labs components, this unit is solidly built. It is constructed with 1/4" and 1/8" thick aluminum plated bolted to square post, resulting in a chassis that provides first rate shielding from external RF fields. On the face plate, three machined gold plated brass knobs function as {from left to right} the selector switch, balance and volume controls. A toggle on the left allows monitoring and another on the right is the mute switch. Least you forget the origin of the component, a large company name plate { gold } will remind you. A red and green LED on the far right indicates operating ready and mute/standby. The component is a simple, not very stylish design, but manages to look impressive never the less.

Technology:

The Pearl is a vacuum tube unit that employs a grounded grid configuration, isolated by a cathode follower stage ahead of and subsequent to the output stage. The stages are non-inverting, thus maintains absolute phase. The grounded grid format is said to provide extremely wide bandwidth and speed { as noted below }. Each { channel } cathode follower has been provided with two pairs of RCA output jacks for those who wish to bi-amplify. All stages are DC coupled with only one capacitor used in the output stage for DC blocking. Separate circuit boards for the audio section and mirror imaging circuitry results in a feedback free design. Wyetech Labs power supply is one of the industries prime examples of technical expertise. It provides constant voltage regulation of the 200 Volts DC power line. This is accomplished with a dual pye filter with two large chokes, a large electrolytic reservoir capacitor, several polypropylene capacitors and an array of high power Zener diodes and produces remarkable energy for the analog circuitry. Like the more elaborate Opal preamplifier, the filter functions passively { only passive components are used } to permit the power supply's "speed" to equal that of the analog circuitry. The filaments are operated by DC with the implementation of a three terminal regulator - a system that provides hum free operation under burden-some conditions. The tube complement is three US-made 6SN7WGTA NOS { new old stock } Phillips dual triodes.

All the technology is accommodated on one solid chassis { see above }, with controls that feel smooth and secure. The volume control is stepped, features gold plated contacts with surface mounted 0.1% precision metal film resistors, providing a channel balance within a tight +/- 0.05dB tolerance. Selector and balance controls are precision Shallco designs with silver alloy contacts. The unit's power transformer is a toroidal design, chosen for it's noiseless operation. Non-magnetic stainless steel and brass hardware is employed throughout and results in a component made to outlast it's owner. However build quality alone doesn't guaranty what this preamplifier is all about...

The Sound:

We connected the preamp to a pair of Audio Aero Prestige monoblocks " reviewed in this issue ", a pair of Sapphire monoblocks by Wyetech Labs { reviewed in Vol. 15 # 2 } and a pair of Bryston 7B SST monoblocks { reviewed in Vol. 15 #1 } We have auditioned all these amplifiers with the Opal preamplifier so we knew what to listen for. The first audition, with the preamp connected to the Sapphire monoblocks, revealed that the Pearl exhibits an almost identical sonic signature to the Opal, although with somewhat limited spatial effects.

Connected to the Audio Aero monoblocks, we found the same overall result, but noted increased resolution, quite audible in upper and lower bass. Curiously, the same results were scored with the big Bryston's in the system. With both auditioning loudspeakers- the Tannoy Kensington's { reviewed in this issue } and our editor's Ethera Vitaes, resolution was razor sharp with tow of the three amplifiers, while with the Sapphires in the setup resolution was not as conspicuous. However, if we had to choose a power amplifier, we'd have difficulty because the { additional ] firmness complemented the overall sound of the two systems, while the Pearl/Sapphire system left all of our listening panel in awe.

Apparent with all the systems was the preamplifier's sonic character: transparent, smooth and with immaculate tonal equilibrium. The Pearl doesn't introduce the pleasant-sounding coloration often apparent with tube designs- nor does it sound sluggish or overly romantic. Fact is, there is no coloration at all, and while this is an important issue for a preamplifier, the type of sound that can be achieved is really in the hands of the end user and his/her selection of power amplifiers. All amplifiers used in this review were what we consider a synergistic match - a harmonious compatibility of components. If there is one element in which the Pearl excels, it's handling of dynamics and it's ability to reach down yonder and up into the ultra high frequency domain without hesitation- speed and effortless. Only when compared to the Opal, can one find some diminished performance attributes. However if we have left you with the impression that the Pearl is an inferior component, that is not our intent. We use the Opal as the only benchmark worthy of comparison as we have yet to find a preamplifier that will outperform it. The Pearl is second only to the Opal, and certainly comparable to the best components the business currently offers.

Synopsis and Commentary:

Over 10 years in business Hebert has demonstrated his engineering skills with all his designs. However, in addition to his obvious design expertise, he has developed a music lovers ear, perhaps the most important accomplishment needed to connect technology to it's intended purpose. In the process, Wyetech Labs components have developed what is commonly known in " the business " as a signature sound that exhibits certain attributes. Common to all Wyetech Labs designs is sonic neutrality - this allows to look { listen } at associated equipment. Nowhere is this more apparent than with the Pearl preamplifier. Although the primary sound of the Pearl is very much the same as the Opal, there are differences: a slightly diminished sound stage, a touch less blossoming { which translates into decreased musical glow } and a slight spatial reduction. However, the Pearl still manages absolute resolution across the audible frequency spectrum for which the Opal sets the standard. The small differences can be heard, but it will take some careful listening and familiarity with the sound of a better component, like the Opal, to tell the difference.

The Pearl preamplifier is a straight-forward component that offers practically no frills, but operates like a preamplifier should, without diminishing or embellishing the sound of the amplifier{s} in the system. This allows the end user to choose a power amp for his/her liking and hear it in a system setup without coloration and without noticing the preamplifiers presence. If you are in the market for a preamplifier but want remote functions and other extravagant options, the Pearl is not for you. If, however, you are looking for a neutral sounding preamplifier of superior quality, you must audition the precious Pearl - it's a gem....