Strange noise from 18

Discussion in 'Amps and Cabs [BG]' started by mikemulcahy, Sep 25, 2001.

  1. mikemulcahy


    Jun 13, 2000
    The Abyss
    I am getting a strange high pitch sound from one of my 18's. Its only audible from the G played on the E string and down. Its kid of like the turbo sound bare heard from a tubo diesel semi engine, or for you non motorheads (not the Lemmy version) I liken it to a tea kettle whistle. Any ideas, this one is new to me.

  2. You might have a hole in your speaker.
  3. mikemulcahy


    Jun 13, 2000
    The Abyss
    Nope, that's the first thing I checked.
  4. does it have a built in cooling fan? and what about the horn.
  5. Luis Fabara

    Luis Fabara

    Aug 13, 2000
    Ecuador (South America)
    Audio Pro - Ecuador
    Could be the voice coil, or that the Port is bad designed.
    The air passing the port could be flowing at more than 0.16 Mach, that would produce a Wisthling sound.

    Its the cab new? Has that sound developed lately?
  6. Make sure that all the cabinets handle screws and the speaker screws... every screw is tight. You may be leaking air.
  7. Ty McNeely

    Ty McNeely

    Mar 27, 2000

    That would be my guess. The lower notes tend to push more air, therefore it may only really be audible with those low notes.

    Does it do it at all volumes or just when its really loud or really soft?
  8. mikemulcahy


    Jun 13, 2000
    The Abyss
    The cab is only 4 months old, and I have 2 that I use. I checked every screw and no dice. It just started and the vulume of the noise does not change with volume of the cab.

  9. Try checking the wiring, poor wiring can cause that or maybe it's feedback, check the magnet.