Dynaco St-70 Upgrade

try triode electronics in chicago. see their web site for upgrade boards.

go to www.avahifi.com If I recall they have a whole upgrade kit that you could do yourself.

I've done two ST-70s with the Glass Audio upgrades from Joe Curcio, and they are wholly new circuits, using only the transformers and the chassis as a basis for what is essentially a new amp which replaces one of the tubes iwth a solid state section.. Parts cost about $250, but you have to be handy to put it together because you actually have two boards to work with rather than one, and one board is located up in the tube area. If you have a shop do it it'll cost about $600, including the parts. -Jay Woodruff