guitar speaker / was Re: Tube challenge!

DCMagnuson at DCMagnuson at
Thu Nov 25 15:02:55 CET 1999

In a message dated 11/25/99 7:28:18 AM Eastern Standard Time, 
Juergen.Haible at writes:

> While it's well known that an *open* output can cause some damage on a tube
>  power amplifier, I nver heard of a constant load resistor instead of a
>  speaker
>  would cause any problems. Is this really true ? And if so, why ?

I was speaking to my service tech that retubed and biased my guitar amp, and 
he said he uses a bunch of high wattage power resistors as a dummy load while 
doing his repairs.  I'm not sure exactly what he uses, (whether or not he 
adds some inductive load or not), but he seems to have no problems doing 

Perhaps some types of output configurations cannot be run like this (Class A, 
etc), but my push-pull amp works fine in this case.

Dave Magnuson
Independent Music Site

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