Roy Mottram of tubes4hifi has sent me a prototype ST-70/ST-120 driver board cover made of a clear heat resistant acrylic. If fits right over the driver board. If you have an existing VTA driver board on your amp, move the four power supply can caps (C13, C14, C15 and C16) to the bottom of the driver board. The interstage caps C1 and C2 also will go to the bottom of the board. You then loosen and temporarily remove the four screws and nuts that hold the driver board to the chassis. Place the clear acrylic cover on the chassis top and replace the screws. Conveniently, there are 4 small holes on the top drirectly over the four bias pots to adjust bias. Contact Roy on the tubes4hifi web site for more info and pricing on the VTA ST-70/ST-120 driver board cover.
Last edited by Bob Latino on Tue Feb 01, 2011 12:43 pm; edited 2 times in total