Follow us on...
Follow us on Twitter Follow us on Facebook Watch us on YouTube
Register
Results 1 to 4 of 4
  1. #1
    On Fire TAMPA VH's Avatar
    Join Date
    07.18.07
    Age
    51
    Location
    Tampa, Florida
    Posts
    331
    Favorite VH Album

    VH2
    Favorite VH Song

    OUTA LOVE
    Last Online

    09.09.11 @ 02:13 PM
    Likes
    0
    Liked 0 Times in 0 Posts

    Default Problem with my Marshall JCM2000 DSL

    Looking for some troubleshooting help here. The last two nights while playing through my Marshall in the ultra gain channel, the sound would randomly fade and then kind of surge back again. I changed cords several times and guitars for that matter, but the problem persists. Any suggestions as to might it may be? I can be jamming away and all of the sudden the overdrive fades out as well as the volume and almost sounds like it is on the clean channel for a moment and then slowly surges back to its normal tone.

  2. #2
    Eruption
    Join Date
    07.03.06
    Location
    Dallas Texas
    Posts
    1,477
    Favorite VH Album

    VHII
    Favorite VH Song

    Light up the Sky
    Last Online

    12.15.17 @ 06:41 AM
    Likes
    162
    Liked 193 Times in 97 Posts

    Default

    could be a voltage fluctuation in your house / studio. Try playing the amp plugged into a voltage regulator w/o anything else plugged into the outlet.
    ~ I like the way the line runs up the back of her stockings ~

  3. #3
    On Fire TAMPA VH's Avatar
    Join Date
    07.18.07
    Age
    51
    Location
    Tampa, Florida
    Posts
    331
    Favorite VH Album

    VH2
    Favorite VH Song

    OUTA LOVE
    Last Online

    09.09.11 @ 02:13 PM
    Likes
    0
    Liked 0 Times in 0 Posts

    Default

    Quote Originally Posted by ScottyBHarris View Post
    could be a voltage fluctuation in your house / studio. Try playing the amp plugged into a voltage regulator w/o anything else plugged into the outlet.
    Thanks bro, i will give it a try.

  4. #4
    Top Of The World
    Join Date
    03.15.04
    Location
    Grand Rapids, MI
    Posts
    160
    Last Online

    08.06.08 @ 04:31 AM
    Likes
    0
    Liked 0 Times in 0 Posts

    If you're good with a DVM and don't mind opening the amp up, check the B+ voltage at idle on the first preamp tube. That should be far enough "down stream" to see if the B+ flux. at all. It should be rock solid at one voltage DC. If it changes, you've got a power supply problem. If you suspect a power supply problem, track the B+ voltage back to the main capacitors, rectifier and power transformer and get some readings. After the caps, the voltage should be NOT fluxing at all (DC).

    Also, don't neglect swapping out your tubes. A bad tube could be pulling the voltage down if its overdrawing current and that could spell trouble if you keep using the amp. try the power tubes first.

    Good luck.

 

 

Similar Threads

  1. Did Ed ever use a Marshall JCM 800?
    By DuffHalen in forum Guitar Room
    Replies: 19
    Last Post: 09.16.02, 04:45 PM
  2. Eddie's Marshall
    By Kamikazesheep in forum Guitar Room
    Replies: 9
    Last Post: 06.27.02, 12:54 PM
  3. Marshall JCM 800?
    By bcgvh in forum Guitar Room
    Replies: 17
    Last Post: 11.18.01, 01:26 PM
  4. Which Marshall Amp
    By Edward Van Halen in forum Guitar Room
    Replies: 9
    Last Post: 05.07.01, 02:54 PM
  5. Marshall Mod..your Opinion....
    By woodman in forum Guitar Room
    Replies: 9
    Last Post: 06.02.00, 12:04 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •