1959HW Power Transformer Hum

Discussion in 'Marshall Amps' started by King_Crimson, Oct 19, 2019.

  1. King_Crimson

    King_Crimson New Member

    Joined:
    Sep 29, 2019
    Messages:
    10
    Likes Received:
    10
    Hi,

    I bought a brand new 1959HW three weeks ago. It works as expected, but there are two things where I'm unsure if they can be a problem.

    First, the power transformer hums relatively loud at 50Hz. Second, what I first noticed yesterday, when switching the power switch from off to on, the transformer (or another near device) sometimes makes a short "bong" sound.

    Did anybody else experience this?

    Regards
     
    tce63 likes this.
  2. G the wildman

    G the wildman Well-Known Member

    Joined:
    Feb 7, 2016
    Messages:
    441
    Likes Received:
    401
    Location:
    London UK
    No - but my JVM did exactly that and it was a spent final. Even though the tubes were newish.
     
    tce63 likes this.
  3. ampmadscientist

    ampmadscientist Well-Known Member

    Joined:
    Jun 26, 2014
    Messages:
    14,012
    Likes Received:
    7,843
    Location:
    Start the reactor... Free Mars!
    It is not normal for the power transformer to hum loudly, it should be almost silent.
    If this amp is new return it to the vendor or take it to the Marshall service center. It should be under warrantee if it is new.
     
    tce63 likes this.
  4. Goldfinger

    Goldfinger Active Member

    Joined:
    Oct 10, 2019
    Messages:
    86
    Likes Received:
    129
    If it's not under warranty, have the transformer repotted.
     
    Last edited: Oct 19, 2019
  5. King_Crimson

    King_Crimson New Member

    Joined:
    Sep 29, 2019
    Messages:
    10
    Likes Received:
    10
    Yes, it should be under warranty. I bought it online, so I have to ask the shop for the return process.

    At another place I read that tightening the transformer screws may remove the hum, but I am not so motivated to disassemble a new amp.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice