"patrick-turner is a **** "
http://www.turneraudio.com.au/Wien-b...scillator.html
** In about 1978, I acquired a used BWD 141 in excellent condition.
Although capable of battery operation, a mains PSU came installed in the
battery compartment. The vast majority of units made had this option fitted.
The custom made, wire wound, reverse log, 15kohm dual potentiometer was the
best thing about it and normally outlasts everything else. I still have two
perfect examples, one in daily use.
Because of using such a beautiful pot, BWD 141s have exceptional frequency
stability.
The typical THD is 0.05% between 100 Hz and 100kHz.
Replacing the original BWD discreet electronics with a pair of NE5532
op-amps and a "phase shifting oscillator" topology reduced the THD to
vanishing levels (circa 0.002% ) at all audio frequencies.
Shame then Turneroid had to butcher his one so badly.
.... Phil