Posted by 2wo [ 71.242.74.68 ] on October 20, 2005 at 22:41:07:
I was playing with the DRD amps today.
I had set them up to run 300b's. All in the name of science of course.
My initial impressions were not as favorable as the 45. In all fairness I did not redo the amp to try to get the most out of the 300b’s and was running them at a lowish current. With the B+ at the 45 level.
So much for science. But hey, I have already decided that this was going to be a 45 amp as the 45’s sound really really good . and the 300b"s have a happy home in the WE91.
Now for the bad news.
When I changed the filament taps, on one amp, I accidentally changed from 5V to 7.5V rather them 2V.
I had 2 meters connected to monitor plate current and bias voltage, and was ramping up the voltage with a Powerstat But did not notice the high filament voltage until it was to late.
So when the tube police come, I will go peacefully…John
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