Laney VH100R Problem, HELP!

Jeebo

Member
Dec 29, 2005
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Hey guys, my amp started acting up today. Everything on my clean channel works fine (including the clean drive) but when I switch to channel 2 there's a very harsh static/fizz and there's virtually no gain (the fizzing only gets worse as I turn the gain up). I replaced the tubes a few weeks ago with JJ E34Ls and JJ ECC83S in V1 through V5 with a matched and balanced ECC83S in the phase splitter. Additionally, when I mess with the voume knob on the guitar the amp makes a crackling sound. Hopefully I can fix this without going to a tech, any insight would be greatly appreciated, thanks!
 
What guitar are you using? Have you tried another guitar through the head?

~006
 
Have you taken your de-oxit or good quality contact cleaner and given all jacks etc. a good cleaning? It's always worth the trouble before you begin a diagnostic...dirty or corroded FX loop jacks in particular, as well as footswitch and input jacks can cause plenty o' problems...give it a quick try.
 
I have tried another guitar through the amp so I was able to isolate it as an amp problem, not a guitar problem. I used contact cleaner on all the new tubes I installed, I'll try the contact cleaner on the footswitch and input jacks

EDIT: just used contact cleaner on the input jacks, footswitch jacks, and speaker output/input jacks. Same problem is still occuring
 
if the clean channel is fine then it must be some B channel preamp tube.

the first 2 tubes on the back are for the clean channel.

the other 4 are for the B channel and PI.

try messing around with some preamp tubes. (replace those 2 of the clean channel with 2 of the B channel in pairs).

see if that helps...
 
i've had the same problem for a while with my ampeg vl-1002

i've swapped a few preamp tubes and still no dice...next step i guess will be to re-tube the entire preamp section, and cross my fingers
 
if the clean channel is fine then it must be some B channel preamp tube.

the first 2 tubes on the back are for the clean channel.

the other 4 are for the B channel and PI.

try messing around with some preamp tubes. (replace those 2 of the clean channel with 2 of the B channel in pairs).

see if that helps...

Christ, that amp has 6 preamp tubes!? That's monstrous...
 
I'll try swapping out the preamp tubes today after class. Wolf, cap = capacitor? where are those located on the amp mainboard?
 
So does the 6505+:rock:
The 5150 III has 8:notworthy

8, good christ, that's unfathomable...I guess it just means that each channel has its own tubes, rather than an overlap, cuz if it was set up the same way as, say, a XXX, which has a RETARDED amount of gain from only 4 12AX7's, that thing would be the fizz monster!
 
I'll try swapping out the preamp tubes today after class. Wolf, cap = capacitor? where are those located on the amp mainboard?

Yep a capacitor. I ran into a problem like that when I was building my SLO. Did a tube change and still had the issue. Traced it back to a bad cap I put on the board.

But if you haven't swapped out preamp tubes yet, it probably is a tube, so no need to worry yet
 
Well I swapped out a couple of the preamp tubes around and they're all working fine in the clean section but are still messed up for the gain channel. Any other guesses before I take it in?