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

    Bias KT88 versus 6550 WE

    Skyfrog
    avatar
    Skyfrog


    Posts : 6
    Join date : 2013-03-03
    Location : Raleigh, NC
    • Post n°1

    Bias KT88 versus 6550 WE Empty Bias KT88 versus 6550 WE

    Post by Skyfrog Sun Aug 09, 2015 7:37 am

    Hi,
    This question was probably asked before but I cannot find this topic. I obtained some Sovtek 6550WE for my M125. Is there a difference in the bias value? Shall I just replace them and re-bias at 0.60/1.20 like the KT88?
    Thanks bunches.
    • Back to top
    Bob Latino
    Bob Latino
    Bob Latino
    Admin


    Posts : 3272
    Join date : 2008-11-26
    Location : Massachusetts
    • Post n°2

    Bias KT88 versus 6550 WE Empty Re: Bias KT88 versus 6550 WE

    Post by Bob Latino Sun Aug 09, 2015 8:28 am

    Hi,

    You would just bias a KT88 and a 6550 in your amp the same ... Just as you said > .60 VDC bias voltage per side for two output tube operation and 1.20 volts per side for four output tube operation. The recommended output tubes to use in an M-125 are 6550, KT88 and KT120. You could also use the newer TungSol KT150 BUT > I don't feel that the extra cost for these (they are about $100 a tube) is worth it ..

    Bob
    • Back to top
    Skyfrog
    avatar
    Skyfrog


    Posts : 6
    Join date : 2013-03-03
    Location : Raleigh, NC
    • Post n°3

    Bias KT88 versus 6550 WE Empty Re: Bias KT88 versus 6550 WE

    Post by Skyfrog Sun Aug 09, 2015 9:57 am

    Thanks Bob.
    • Back to top
    Sponsored content

    Sponsored content


    • Post n°4

    Bias KT88 versus 6550 WE Empty Re: Bias KT88 versus 6550 WE

    Post by Sponsored content

    • Back to top
      Current date/time is Fri Nov 08, 2024 2:13 am