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FERNSEH · 28th Jan 2010, 10:29 pm

In the world of audio there is a great interest in the use of the PL509 as an audio output valve. Evidently, the trick is to supply the audio signal to the screen grid of the valve. The control grid can be connected to ground if auto cathode bias is used. Alternatively GI can be supplied from a negative bias source, in which case the cathode is returned to ground. Has any forum member tried the EL or PL509 in such an application?

DFWB.

28th Jan 2010, 10:29 pm	#1
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	EL or PL509 as an audio output valve. In the world of audio there is a great interest in the use of the PL509 as an audio output valve. Evidently, the trick is to supply the audio signal to the screen grid of the valve. The control grid can be connected to ground if auto cathode bias is used. Alternatively GI can be supplied from a negative bias source, in which case the cathode is returned to ground. Has any forum member tried the EL or PL509 in such an application? DFWB.