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Re: 6BQ5 "cherrying" - what's going on??

AhhHaaa....
Went through that last week for the second time.
Observations/questions:
1. Are you running the stock circuit boards? If they are warped due to the pretty hot setting with the stock 90 ohm cathode resistor, those solder lines on the backside may be cracked or one of the wires shorting out against a connection point (my situation).
2. I rebuilt both boards using new ones (can't remember the guys last name, Steve is his first) and all new components. Like night and day.
3. Last week after having one odf the Mullard tube making a bunch of noise and going "cherry" I discovered a cold solder joint off pin 3. Replaced it and the amp is quite as heck and actually is very nice sounding for my office bookcase application.
One side runs a pair of NOS Sylvania blackplates and the other channel is a pair of used Mullards.
4. Now ai did something a bit different and replaced the stock cathode resistor with a 25 watt 250 ohm rheostat that fit very snugly in the back of the amp. Lets me set the bias for the tubes - I've noticed a huge variation in current draw of the 6BQ5's.

Good Luck!


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  • Re: 6BQ5 "cherrying" - what's going on?? - JSTRM 08/1/0506:56:38 08/1/05 (0)


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