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DHT fixed bias schematic


2010-12-02 5:06 pm
Hi all.

I have been playing with a pair of 1H4G tubes.
I have been trying to locate a schematic for a fixed bias DHT...or a good explanation of one- simple if possible.

With the DHT's I'm using now, I have 2V going through the filament via a separate 5vdc supply.
I am using LEDs to bring the 5V to 2V before it reaches the filament. The filament goes straight to ground.

I'm using a Class A SE circuit no feedback...basic, basic circuit.
I have good sound...but it lacks bass. I know I can get more out of them.
Detail and imaging is good...good enough to keep trying DHT's...addictive...worse than chocolate.

Any help would be appreciated.

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