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    VTA ST70 power transformer heat

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    rymi

    Posts : 21
    Join date : 2017-05-20

    VTA ST70 power transformer heat

    Post by rymi on Mon Jun 26, 2017 1:45 pm

    What is the voltage rating of the transformer used on the vta st70?
    Is there a temperature rating on them as well?

    I am curious because I find its hot after and hour or so. I figured the beefier transformer would be much cooler than my old stuff. most of which runs very hot. So hot you couldn't keep your hand on some of them for 5 seconds without injury.

    The VTA ST70 also runs hot after about an hour, but less so than old gear... I could keep my hand on it at the end of a listening session for 5 seconds but little more than that would likely burn. I haven't measured it yet with a thermometer.

    Line voltage at my house is usually right on 120. Im running a pair of 8 ohm speakers.
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    Bob Latino
    Admin

    Posts : 2583
    Join date : 2008-11-26
    Location : Massachusetts

    Re: VTA ST70 power transformer heat

    Post by Bob Latino on Mon Jun 26, 2017 2:06 pm

    rymi wrote:What is the voltage rating of the transformer used on the vta st70?
    Is there a temperature rating on them as well?

    I am curious because I find its hot after and hour or so. I figured the beefier transformer would be much cooler than my old stuff. most of which runs very hot. So hot you couldn't keep your hand on some of them for 5 seconds without injury.

    The VTA ST70 also runs hot after about an hour, but less so than old gear... I could keep my hand on it at the end of a listening session for 5 seconds but little more than that would likely burn. I haven't measured it yet with a thermometer.

    Line voltage at my house is usually right on 120. Im running a pair of 8 ohm speakers.

    Every summer we seem to get these questions about tube amps and heat .. What you are experiencing is perfectly normal .. See link below from 2011 ..

    Tube amps and heat

    Bob
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    j beede

    Posts : 417
    Join date : 2011-02-07
    Location : California

    Re: VTA ST70 power transformer heat

    Post by j beede on Mon Jun 26, 2017 9:55 pm

    If you can keep your hand on the PT for 5 seconds you are likely below 50°C. Not a problem. I bias the output stages of my class A solid state amps to run 50°C continuously (winter season amps).

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