Username: Password:

Author Topic: How ironic  (Read 1238 times)

Woogie

  • Lightweight
  • ***
  • Posts: 906
How ironic
« on: December 16, 2007, 02:17:42 PM »
I sit down to make you guys some Holydiver/slowhand/JCM800 clips and my JCM has blown a valve or two.

How do I diagnose if it's blown a valve? I`ve tapped them all with pencils and they sound the same. They look the same as usual. It just crackles and makes a loud squeeling when I turn it on.

What's caused this? I did what I always do. The valves aren't even that old. I don't want to replace them all cos it costs a fortune.

Cheers

HTH AMPS

  • Middleweight
  • *****
  • Posts: 5649
    • HTH AMPS
How ironic
« Reply #1 on: December 16, 2007, 02:25:08 PM »
pull the EL34s one at a time and see if the noise stops.  of course you'll still need one of them in the amp to get any sound.  

 :twisted:

38thBeatle

  • Middleweight
  • *****
  • Posts: 6098
    • http://www.myspace.com/alteregoukband
How ironic
« Reply #2 on: December 16, 2007, 02:38:06 PM »
Why not use the VC30 for now.When you get the JCM running do another clip for comparison (he says as if making a clip is something he does every day).
Send three and fourpence we're going to a dance
BKP's: Apache, Country Boy, Slowhands.

Woogie

  • Lightweight
  • ***
  • Posts: 906
How ironic
« Reply #3 on: December 16, 2007, 02:48:40 PM »
Quote from: HEAVIER THAN HELL
pull the EL34s one at a time and see if the noise stops.  of course you'll still need one of them in the amp to get any sound.  

 :twisted:


Are you sure?!?!

Quote from: 38thBeatle
Why not use the VC30 for now.When you get the JCM running do another clip for comparison (he says as if making a clip is something he does every day).


Yeah I made a Laney clip with a Zakk OD running through it but its .amr and I dunno how to convert/chop it.

HTH AMPS

  • Middleweight
  • *****
  • Posts: 5649
    • HTH AMPS
How ironic
« Reply #4 on: December 16, 2007, 03:11:03 PM »
I wouldn't have said it if I wasn't sure.  Remove the EL34s one at a time, if one is dodgy the noise will stop when it's removed.

If the noise doesn't stop when you've ruled out all the EL34s, move on to the ECC83s starting with V1 (the one closest to the input).

Have you got any spare ECC83s? - if so try swapping the ones in your Marshall one at a time to identify the dodgy one.

 :twisted: