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BF Princeton Reverb. Add 100 Ohm Heater/Lamp Resistors?

8/30/2003 4:11 AM
BF Princeton Reverb. Add 100 Ohm Heater/Lamp Resistors?
I have a '67 BF Princeton Reverb (Tube chart AA764, GZ34 Recto)that came bone stock without the pair of 100 Ohm resistors tied to the heater /lamp as shown on the AA1164 layout.  
The amp sounds great but hums a little when I turn the volume past 4.  
I added the 100 Ohm resistors. The hum stopped, but I noticed that the amp now gets very hot to the touch. The chassis, the faceplate, even at idle the PT is almost too hot to touch with a bare hand.  
Plate voltage is 433V at ~20 mA, and remained constant before and after adding the resistors.  
Naturally I prefer the amp with the least amount of hum.  
Is the additional heat anything to be concerned about?  
What are the consequences, if any, of adding 100 Ohm resistors if the amp already has a center tap?  

Daver If you add the resistors you need t... -- 8/30/2003 3:55 PM
Mark Lavelle [QUOTE]Is the additional heat anyth... -- 8/30/2003 3:58 PM
Spencer Please excuse my ignorance, but how... -- 8/30/2003 4:58 PM
Spencer The AA1164 and AA964 layouts show a... -- 8/31/2003 6:02 AM