Mods for DYNA ST-70, What do you think??

I have a old Dynaco ST-70, what to do. Put new caps and tubes, maybe a new board. Should you leave it stock and up-grade parts or modify it. If so what kind of modification?

autospec03-31-2002 4:55am

Showing 2 responses by twl

twl Details Discussions Posts This discussion Message User 3,251 posts 03-31-2002 at 02:24pm Copy Comment URL Report Comment Edit Delete www.avahifi.com/70rebuild.htm This site has a reprinted article that explains in depth exactly how to rebuild/upgrade a Dynaco St-70. Very long, extremely detailed, step-by-step instrucions. I think you will find it very informative. It's on the Van Alstine website. He is currently no longer modding the St-70, but his does offer a complete re-make of the amp with new circuit board design using your old chassis and transformer.
twl Details Discussions Posts This discussion Message User 3,251 posts 03-31-2002 at 01:22pm Copy Comment URL Report Comment Edit Delete I agree with Sean's good advice. Also,the ST-70 could definitely benefit from power supply upgrades especially in the filter caps, for increased headroom. Doubling the microfarad amount is not uncommon. Frank Van Alstine has been doing excellent mods/rebuilds on these old Dynaco's for years. He would be the first place I would check. He used to offer complete mod packages, in stages, for reasonable money. Probably still does. He's an old timer and he knows what he's doing, especially with Dynaco.I think his company name is Audio by Van Alstine.

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