Discussion in 'Amps and Cabs [BG]' started by zillo, Sep 2, 2004.

  1. zillo


    Jun 5, 2003
    Here's the deal. I was practicing in the family room tonight and noticed a wavering in my volume level (not that high to begin with) . I stopped for a minute and started again and everything seemed fine.

    Tuned things off, took a break and came back. When I started again, there was a bad "vibration" or buzzing sound. It seems to be coming from both speakers and the tweeter.

    I tightened the screws on the speakers and the grill, checked the cable change.

    I have a yorkville xm100 and tried the bass in that (it's a Jack casady bass) and that sounds fine.

    The rig is a Warwick ProFet II amp, solid state and an Avatar B212.

    Have I fied something in the amp...fuse? Help...I don't have a clue!
  2. Sounds like an electronic fault in the amp to me.
    Get a serviceman to check it out and don't use it or you may cause more damage.
    Don't panic just yet, it may only be a small component failure that won't cost the earth to fix.
    Let us know how you get on. Good luck.
  3. Oh yeah, if you let us know what area you live in, TB members may be able to recommend a reputable repairer for you.
  4. zillo


    Jun 5, 2003
    Thanks for the suggestion. It does sound like an electrical problem.

    Pretty irritating in a 15 month old head!
  5. Have you verified that the speaker leads are attached properly inside the cab?
  6. Take the head off the cabinet, just in case there is a vibration-induced problem.

    Borrow another head and try that. This will isolate the bug to either the head or the cab.
  7. If its a solid state amp it sounds likea fault on the power amp stage, does the speakers make a pulsing noise with no bass guitar input, if so the power amp has a fault.

    I had this twice with my Ashdown head after i pulled out and re-connected a cab while the amp was still on, woops !!
  8. 4Mal

    4Mal Supporting Member

    Jun 2, 2002
    Columbia River Gorge
    Bruce is dead on. Try to isolate the issue and solve from there ...
  9. zillo


    Jun 5, 2003
    Well, it's the amp. I tried it with a different cab, same problem.

    With no bass input, it's dead quiet, like it should be. Hitting a bass string causes the ho;;ow, vibration sound, overlaying the note played. Weird.
  10. Anything else silly, such as using a guitar (coax) cable instead of the correct wire to connect the cab... ?

    My SWR IOD can do this on occasion, because it has a flaky Standby switch. If your amp has jacks for Effects Send/Receive, these can be dirty. Work them (and the speaker jacks) a number of time with a plug. Power off, of course.

    Remove the fuse, clean both ends with a pencil eraser and some alcohol to get rid of finger prints. Examine the fuse, replace the fuse. Try various volume/tone control combinations.

    In short, go through all the possible permutations of settings on your amp head. If you can isolate it down to something specific, the repair bill will be less.