Playing through a head with a load and no speaker and I hear sound from the head

Discussion in 'Amps and Cabs' started by Gallery, May 21, 2015.

  1. Gallery

    Gallery Supporting Member

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    I've got my 5e3 plugged into the Aracom. The Aracom is set to load. No speaker is hooked up. When I strum the guitar I hear noise coming from the head. It's a very faint buzzy amplified sound of the guitar that gets louder when I turn up the amp volume and quieter when I down the amp volume.

    Is this normal?


    I usually have the line out running to the Torpedo CAB or the DAW and headphones on so I've never noticed this before now.
     
    wizard_23 likes this.
  2. tone?

    tone? Supporting Member

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    Absolutely.
    It's the output transformer.
    Not to worry at all.

    If you turn the amp a bit down it will stop.
    But it's totally normal and won't harm anything.
     
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  3. Gallery

    Gallery Supporting Member

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  4. J M Fahey

    J M Fahey Member

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    Magnetic materials such as transformer iron stretch and contract with varying magnetic fields ... exactly what you have in a transformer, so it will (poorly) reproduce what you are playing through it.
    Normally swamped by what a real speaker puts out, in a silent Lab it can be heard.
    All transformers do it by the way, a power transformer is always "playing" 50/60 Hz which you hear as a faint hum.
    As a side curiosity, power transistors also "sing", although in that case it's the crystal vibrating, not unlike a Piezo tweeter.
     

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