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So...just got a 2204...playing it the other night, when all of a sudden...snap...dead...
Took it apart, the only thing i could find was the mains fuse popped...i had a new set of tubes, so i went and got some resistors to mount to take the bias readings...put the old tubes back in to get an idea on how the bias pot works, and can't get a measurement out of the one tube...so, it must've died...put the new tubes in, biased, and back to playing

Back in March, i bought a Laney GH50L...it didnt have the resistors either, so i figured while the soldering iron was out, i'd do it to this amp as well...put the tubes back in and checked the bias, depending on how to you want to read mv or ma, i dunno who put them in this amp, but there was a 42m a/v difference between the two tubes (one read 42 and the other read 84)...i had a spare JJ kcking around, so, testing to ensure it wasnt operator error, i put it in...only 15m v/a difference...better, but looking like it'll need a new set of tubes

It suprised that the tubes would be THAT mismatched...
It was also a little suprising to see that each tube in the 2204 was direct grounded, while the laney grounds for both tubes were wired together and then to ground...i had wondered if that was causing the wild reading until i switched the tube

Anyways..just wanted to share...
And my word...they are LOUD!
 

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So...just got a 2204...playing it the other night, when all of a sudden...snap...dead...
Took it apart, the only thing i could find was the mains fuse popped...i had a new set of tubes, so i went and got some resistors to mount to take the bias readings...put the old tubes back in to get an idea on how the bias pot works, and can't get a measurement out of the one tube...so, it must've died...put the new tubes in, biased, and back to playing.

Back in March, i bought a Laney GH50L...it didnt have the resistors either, so i figured while the soldering iron was out, i'd do it to this amp as well...put the tubes back in and checked the bias, depending on how to you want to read mv or ma, i dunno who put them in this amp, but there was a 42m a/v difference between the two tubes (one read 42 and the other read 84)...i had a spare JJ kcking around, so, testing to ensure it wasnt operator error, i put it in...only 15m v/a difference...better, but looking like it'll need a new set of tubes

It suprised that the tubes would be THAT mismatched...
It was also a little suprising to see that each tube in the 2204 was direct grounded, while the laney grounds for both tubes were wired together and then to ground...i had wondered if that was causing the wild reading until i switched the tube

Anyways..just wanted to share...
And my word...they are LOUD!
You might want to check the resistors' values to make sure they're not off spec. Also, you might have a bias supply issue to one of the tubes. Probably not a bad idea to check both their bias voltages.
 

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It was also a little suprising to see that each tube in the 2204 was direct grounded, while the laney grounds for both tubes were wired together and then to ground...
-ezycome

It is the same thing : Different wiring for the same job. It's class AB amp
 
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