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+:headbang:
The 5150 III has 8:worship:

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?