The Dynaco Tube Audio Forum

Would you like to react to this message? Create an account in a few clicks or log in to continue.
The Dynaco Tube Audio Forum

Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Tubes4hifi VTA tube amp and preamp kits and all Dynakitparts.com products


2 posters

    Optimal voltage for our amps

    Mr C
    Mr C


    Posts : 99
    Join date : 2019-07-11
    Age : 69
    Location : Visalia CA.

    Optimal voltage for our amps Empty Optimal voltage for our amps

    Post by Mr C Wed Sep 30, 2020 1:55 pm

    I'm wondering if there is an optimal voltage for our amps. I've read they should be okay up to 120. The use of a variac is recommended. Also a bucking transformer can be used. My variac is usually set to 116-118. I was playing with a bucking transformer and I get about 110 off one tap and 120 off the other tap when my mains are at 124+. Is 110 too low? So I'm wondering what is the sweet spot? At what voltage are these amps running exactly in spec as designed?
    avatar
    Guest
    Guest


    Optimal voltage for our amps Empty Re: Optimal voltage for our amps

    Post by Guest Wed Sep 30, 2020 6:12 pm

    .


    Last edited by PeterCapo on Fri Dec 04, 2020 2:08 pm; edited 3 times in total
    Mr C
    Mr C


    Posts : 99
    Join date : 2019-07-11
    Age : 69
    Location : Visalia CA.

    Optimal voltage for our amps Empty Re: Optimal voltage for our amps

    Post by Mr C Wed Sep 30, 2020 6:29 pm

    I have a VTA ST-120, So that's what I'm asking about. I usually have to make small adjustments on the variac when I turn on the system. Bucking transformers give a percentage voltage reduction. Like 7% - 12% depending on transformer. As for VTA amps I was wondering what the sweet spot voltage is.
    avatar
    Guest
    Guest


    Optimal voltage for our amps Empty Re: Optimal voltage for our amps

    Post by Guest Wed Sep 30, 2020 6:50 pm

    .


    Last edited by PeterCapo on Mon Nov 30, 2020 4:41 pm; edited 1 time in total
    avatar
    Guest
    Guest


    Optimal voltage for our amps Empty Re: Optimal voltage for our amps

    Post by Guest Thu Oct 01, 2020 6:51 pm

    .


    Last edited by PeterCapo on Mon Nov 30, 2020 4:41 pm; edited 1 time in total
    avatar
    audio ken


    Posts : 13
    Join date : 2020-09-08

    Optimal voltage for our amps Empty Re: Optimal voltage for our amps

    Post by audio ken Fri Oct 02, 2020 5:11 pm

    I have seen mention on this forum that some folks use UPS or “power unit/conditioner” with AVR. I tested the output voltage on my Monster power unit and was alarmed to find it at 125v. Subsequently my APC ups with AVR also had output of 125v. I called 2 manufacturers and they claim it’s within 10% of 120v so performing as expected. My choice is to get power company to turn down the juice at the transformer near my house or install my bench variac in my main system and set it to 119v, then connected my APC ups to it and the lcd screen shows output of 119v. Of course I did the latter for now and listening to this fine amp with no worries of shortening life of tubes or the entire system. I once had an ARC blow tubes and resistors and an expensive visit to ARC repair tech made me very wary.

    Sponsored content


    Optimal voltage for our amps Empty Re: Optimal voltage for our amps

    Post by Sponsored content


      Current date/time is Thu Mar 28, 2024 4:34 am