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Old June 4th 05, 02:37 PM
Chuck Harris
 
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gil wrote:
Just recently got a HW-101, with low power out,I can get a few more
watts by adjusting the bias slightly above the 20ma mark, how safe is
it this?
Since I dont have spare 6146's what should I be looking for that could
be a problem other than the finals?

Thanks in advance...Gil


Sorry, but the finals are the usual reason for low output. You will go
through many sets of finals before you wear out the driver.

Make sure that your replacement finals are 6146, or 6146A's, never B's!

Note, 6146W's can be all three types. The later 6146W's are B's.

Don't get creative with the bias. It has nothing to do with the power
output, but everything to do with balancing tube life with low distortion.

When your bias is low, your tubes are cut-off on opposite cycles, and you get
cross over distortion. When your bias is high, the tubes are approaching
class A operation where they make a good expensive short lived shack heater.

-Chuck