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    Dyna MK III driver boards


    Posts : 3
    Join date : 2013-05-08

    Dyna MK III driver boards Empty Dyna MK III driver boards

    Post by billy-toby on Wed May 08, 2013 9:33 am

    Hi Folks,

    Newbie, here--not to Dyna, but to this forum.

    Personally, I’m partial to anything made by Latino or Mottram, but without a full grasp of circuitry, I admit this is a subjective preference.

    My questions are, among the several driver-board replacements for Dyna MK III and IV amps, what are their differences and which board is likely to deliver the best performance?

    Same questions, really, for the power-supply options. On this latter, Latino seems to prefer dropping-in a larger quad capacitor, while other suppliers offer PCBs stuffed with diodes and electrolytic caps.

    In short, I don't know which way to go and would appreciate any help with these issues.

    Thanks much in advance.

    Sincerely, Bill


    Posts : 188
    Join date : 2010-03-07
    Age : 81
    Location : Houston Texas

    Dyna MK III driver boards Empty Re: Dyna MK III driver boards

    Post by stewdan on Wed May 08, 2013 2:49 pm

    Hi Bill --- I can comment on some of the Boards avaialable for the Dynaco Mk IIIs.

    Modern Clones of the Original Stock Circuit -- had a pair and were very easy to set up since all original wiring connects to the clone boards plus you have modern parts.

    Triode Electronics Mk 3 Board --- have a pair with these boards and they were very easy to set up since 99% of the wiring is the same except for a ground wire. Also have modern parts. IMHO, they also sound better than the stock boards.

    VTA Board -- have a pair running 12AU7s. More difficult to set up than the Triode or Stock Boards becuse of VTA wiring differences, but IMHO sound much better than the previous boards. Roy supplies documentation and there are other people on the forum who have built these.

    VTA Board --- also have a pair running 6SN7 Octal tubes. Wiring is the same as VTA/12AU7. I prefer the Octal version of the VTA boards, the 6SN7's sound better to my ears.

    Poseidon Boards -- (By Shannon Parks (DIY Audio)) Modern PCBs, with fantastic Silk Screening. Except for a few items, Parts are very afforable and these are, at least to me were easier to set up than the VTA Boards. I rebuilt a pair of Mk III's for a friend with these and in the short time I had them, I thought they sounded pretty good. Do a Google scan on "Poseidon PCB PDF" and you will find several versions of the documentation.

    I also have some Mk3's with Quad Caps and some with SDS type Cap Boards. No real preference here. But, please note that while you could unsolder and remove and then reuse the original Dynaco/Sprague Quad Caps, some of modern versions are not as durable after removal (Material Differences??).

    I hope this info helps.

    Have fun,

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