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    VTA ST120 - is it necessary to power off amp to change speaker wire?

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    guentherj2

    Posts : 50
    Join date : 2013-06-22
    Location : Bellingham, WA

    VTA ST120 - is it necessary to power off amp to change speaker wire?

    Post by guentherj2 on Sat Mar 01, 2014 9:04 pm

    Greetings all.

    I'm testing different speaker wires and was wondering if it is OK to disconnect and reconnect speaker wire without powering off the amp. Of course I would not play any source during changing.

    Thanks,

    John

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    Guest

    Re: VTA ST120 - is it necessary to power off amp to change speaker wire?

    Post by Guest on Sat Mar 01, 2014 10:02 pm

    well there are different schools of thought here.
    Some say its ok as long as the volume is turned down and no signal input.
    Some say it could cause problems with the output tubes and/or output transformer.
    Myself, I tend to err on the side of caution and would turn mine off, even if its only for swapping out speaker wires, thats just me.

    peterh

    Posts : 679
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: VTA ST120 - is it necessary to power off amp to change speaker wire?

    Post by peterh on Sun Mar 02, 2014 4:45 am

    guentherj2 wrote:Greetings all.

    I'm testing different speaker wires and was wondering if it is OK to disconnect and reconnect speaker wire without powering off the amp. Of course I would not play any source during changing.

    Thanks,

    John
    I think the st-120 is stable under this BUT
    to be shure you could connect / install a resistor 100ohm/5w across the speaker outputs on the amp, thus giving the amp some load under any circumstances. It's small enough
    load not to affect power but large enough to prevent surplus voltages.
    In fact, it should imho be installed as standard component.

    guentherj2

    Posts : 50
    Join date : 2013-06-22
    Location : Bellingham, WA

    Re: VTA ST120 - is it necessary to power off amp to change speaker wire?

    Post by guentherj2 on Sun Mar 02, 2014 4:42 pm

    Interesting. I also tend to err on the side of caution so for the time being I'm having to power on and off and waiting which makes the comparison challenging.

    So you (peterh) keep a 100ohm/5w resistor across each of your speaker output terminals on your amp? This has no affect on sound when playing music?

    Thanks for the feedback. I'll wait for more before doing anything differently.

    peterh

    Posts : 679
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: VTA ST120 - is it necessary to power off amp to change speaker wire?

    Post by peterh on Sun Mar 02, 2014 4:59 pm

    guentherj2 wrote:Interesting. I also tend to err on the side of caution so for the time being I'm having to power on and off and waiting which makes the comparison challenging.

    So you (peterh) keep a 100ohm/5w resistor across each of your speaker output terminals on your amp?  This has no affect on sound when playing music?

    Thanks for the feedback. I'll wait for more before doing anything differently.
    No i don't since i do not change speakers and they are connected with screw terminals.
    But when i know that speakers might be interrupted installing a resistor will be an extra insurance. I have done this at other installations.
    It has negligible impact on sound ( speakers are a very much more demanding load!).

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