The bulky pre-amplifier KE83-92B seen in this page is my second attempt in designing a modern, good and cheap pre-amplifier for my Williamson Power Amplifier KEW88-91D+. It all started as a somewhat desperate attempt in incorporating not only differential MC drive but also a 20 dB gain stage for direct Williamson PA drive. Ordinary 6SN7's were used for this purpuse because they are quite linear and has low but sufficient gain (especially while using the Edison Effect). After testing it however became clear that differential 6SN7 use with ac heating was out of the question. I therefore disconnected the differential input stage and used the MM cascade stage only. This however still left me with quite a humming device (-20dBU). But it sounded great... With the use of a "novoct"-adaptor almost any popular tube would make the amp happy. What crazy ideas! The chassis is made of solid oak.

Main Data:
Power Consumption (D trafo): 150W(!)@230V/50Hz
Supply Voltage: 2X300Vdc/20mA
Heater Supply: 4X6.3Vac/0.6A
Pick-Up Sensitivity: 5mV@47k//150pF
Miscellanous I/O:
1) RIAA-out: 150mV@330R
2) Source-in: 150mV@1M
3) Pre-out: 1.5V@4.7k (inverted, 20kHz@17m*100pF/m)

KE83-92B, Roger's Pre-Amplifier Mk II using Sovtek 6SN7GT's.

More info:
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KE83-92B, Mk II Circuit Diagram
KE83-92B, Mk II Component List
KE83-92B, Bottom View