Home » Audio » Pro Sound » Marshall vs 65 has barely no sound even with new tube
Marshall vs 65 has barely no sound even with new tube [message #27375] Wed, 27 December 2006 20:40 Go to next message
Mike rocker is currently offline  Mike rocker
Messages: 1
Registered: May 2009
Esquire
Hi everyone, i bought a used marshall vs 65 amp and used it without any problems for about 3 years,then all of a sudden the sound faded out while practicing, i just replaced the Ecc 83 tube but it still has the same problem ,i can barely hear the guitar even if it-s cranked to 10, any help would be appreciated...

Re: Marshall vs 65 has barely no sound even with new tube [message #27412 is a reply to message #27375] Wed, 18 April 2007 11:19 Go to previous message
Adrian is currently offline  Adrian
Messages: 3
Registered: May 2009
Esquire
Hi
May be too long ago you posted question for this to help. Just fixed a VS65R with exactly same problem. R19 1/2W 100K had gone open circuit, this is the resistor that the valve outputs across to drive the rest of the pre amp stage, so absolutely vital. The reason you get a bit of sound is the residual capacitance of the resistor allowing very small modulation of voltage. WARNING, this circuit has no bleed resistor across the 300v capacitors supplying the valve (C6 and C7) discharge these with a high value resitor prior to touching the back of the pcb or you wont be amused.
Hope it Helps!

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