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harp · 06-17-2009, 08:49 PM

I am a beginner at amp mods. I have a JCM 900 that I'm trying to re-tube with EL34's. I changed the screen resistors to 1K and changed the bias resistor. I'm able to bias the thing just fine but the amp is getting hot. The plates don't seem to be glowing red, but the tubes are getting hot enough to make the face plate hot to touch. Does anyone know what might be going on?

06-17-2009, 08:49 PM	#1 (permalink)
harp Junior Member Join Date: Jun 2009 Posts: 18	JCM 900 6l6 to EL34 Conversion problems I am a beginner at amp mods. I have a JCM 900 that I'm trying to re-tube with EL34's. I changed the screen resistors to 1K and changed the bias resistor. I'm able to bias the thing just fine but the amp is getting hot. The plates don't seem to be glowing red, but the tubes are getting hot enough to make the face plate hot to touch. Does anyone know what might be going on?