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Re: Quad II's

Hi
I used to own a pair of those babies. I miss them. :^(
It looks like the chinese? KT-66 are not up to spec.
You may want to search the tube asylum for the most rugged KT-66, buy two MATCHED pairs or do a simple mod: increase the value of the cathode resistor by 10%.
This mod will decrease the KT-66 plate current. The amp was designed to run on 110 Volts and is probably seeing 125 V, if your electricity company is as greedy as mine (they sell KVA, not current). A higher voltage means more money out of your pocket, with the same appliances running.
While you have the Quad II hood open, replace the coupling caps (from EF86 plate to KT-66 grid) and the cathode bypass electrolytic caps (in paralell with the cathode resistors). These caps sometimes go leaky and may cause cherry-red plates.
I hope this helps
Carlos


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  • Re: Quad II's - Carlos 03/22/0419:39:12 03/22/04 (0)


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