Wyetech Labs Pearl 105 Linestage Pre

Wyetech Labs “Pearl” line stage preamp in very good condition.  Only a few hundred hours usage over time while set-up. Clear plexiglass top ... the way I received it ... no metal top in hand.  No noticeable marks or scratches on paint (see photos). These limited, hand built products have very high-end parts and are well constructed - originally with a 10 year warranty that speaks to its durability. See Wyetech Labs review links for more information if interested. 

Highly unusual then, Roger Hebert consumes tube-related noise and bandwidth issues of amps and preamps for breakfast well before following Alice down the rabbit hole into the lab. On his currently second-from-the-top non-inverting Pearl preamp, this translates into an ungodly +0/-3dB bandwidth of 3Hz to 950kHz (the ruler-flat spec is 15 - 200,000Hz) achieved with a grounded grid circuit bracketed by cathode followers fore and aft and three 6SN7WGTA NOS Phillips double triodes. While we're at specology, add input impedance of 50Kohm, output impedance of 600 ohms, output voltage of 3.5 Vrms (max 8.5) and slew rate of > 25 Volts/microsecond.

Single-ended connectivity provisions include 4 inputs, one tape loop and two pre-outs, with an international voltage switch, power IEC, fuse holder and power mains toggle completing the rear estate. The large gold-plated frontal brass controls, from left to right, select inputs, balance offset (+/- 5dB in 1dB stepped increments) and volume (24 click-stops from -60dB to 0dB). One toggle selects between tape/source, another between mute/on, this latter connected to two LEDs (one red for mute, one green for ready which lights up once a relay completes the initial 45-second thermal stabilization process).

Anything from the house of Wyetech is a mixture of only slightly gussied-up yeoman build and -- at their models' respective price points -- the finest parts that money can buy. The Shallco switches and ELMA volume control of the Pearl redefine the term "positive action" and the point-to-point wiring of the zero NFB linestage utilizes advanced two-sided Vector boards with contact turrets for the shortest possible signal path. The separate 200V/DC power supply board borrows from the top-line Opal with a double-pye choke filter, a large 30uF final polypropylene capacitive filter, a 2000uF electrolytic capacitor to passively shunt-regulate the 200 volts DC and a solid-state regulator on the filaments.


The chassis in the trademark lavender automotive paint bolts 1/8" to 1/4" thick aluminum plates to square corner posts via non-magnetic stainless steel screws for no-nonsense solidity. A 10-year warranty reflects on the maker's confidence in the trouble-free longevity of his product. The stock NOS valves are expected to last for 10,000 hours or more.