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    PH 16 happiest at 117 or 120 volts?



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    Join date : 2015-05-19

    PH 16 happiest at 117 or 120 volts?

    Post by Dougbot on Wed May 24, 2017 3:44 pm

    Hi All,

    I currently have my VTA ST70 plugged in to a variac to feed it 117 volts AC as recommended by many posts on this forum to extend tube life and go easier on the transformer.  The other piece of tube gear in my system is a VTA Ph 16.  I currently have it plugged in to the 120 volt wall outlet (not the variac), but I'm wondering if it would be happier if I ran it through the variac as well.  Is the Ph16 circuit designed for 120 since it is a "modern" design, or is 117 a universally preferable voltage for tube gear?



    Posts : 1403
    Join date : 2008-11-30

    Re: PH 16 happiest at 117 or 120 volts?

    Post by tubes4hifi on Fri May 26, 2017 1:57 pm

    Hi Doug,
    should work just as well either way. The important factor is that you have a minimum of 20vdc across D3 in the power supply. If you have less, you'll have hum.
    If you have more, that's fine.

      Current date/time is Wed Mar 21, 2018 12:43 am