Mesa mk 3 no gain on the lead chanel

[murray sanders]

Mesa mk3 blue stripe no gain
The mesa has no gain on the lead chanel at all and the volume is quite although it can be attenuated , the clean chanel works as it should , anyone had similar issues , change all the tubes made no difference

 

[lovetoboogie]

I have had several Mark III's come in over time with the same symptom... first check the v3 preamp tube... if good, next check the v3 plate load resistors. Both the A & B sides. Measure voltages at Pin 1 and Pin 6...I have had to replace the v3b plate load resistor on more than one Mark III...

 

[McBarry]

while inside, chopstick around V3. I've had the odd dry joint that looked AOK..and a coupling cap that was almost fallen out, courtesty aging solder,,,

 

[dlpasco]

while inside, chopstick around V3. I've had the odd dry joint that looked AOK..and a coupling cap that was almost fallen out, courtesty aging solder,,,

My Mark III lead drive failed several years ago and had to go into the shop to get fixed. It was apparently a bear to get to, so hopefully what you're experiencing is simply a tube issue.