Biasing VTL Triode-25's Older Version


Hi All -

If anyone can help with this question, that'd be great. I have the older version Triode 25's (red chassis) and the biasing points are not immediately accessible. Bea Lamm at VTL gave me instructions for biasing this amp, and it says to remove the bottom cover to access bias measurement points and trim pots. However, the Triode 25's don't really have a "bottom cover" per se. Their red chassis extends up both of the sides as well as the bottom (3 faces to this piece, and a bunch of screws attaching it to both sides). In order to gain access to the bottom, the entire 3-side piece would need to be removed.

Can any one tell me if this is the way to access the bias points. Perhaps what appears to be a red chassis is really more like a red sleeve - and it just needs to be slipped off. It's a lot of screws to remove to get to the bias points though.

Thanks for any info you can provide.
peter_s
I have had those amps in the past. Just unscrew all the little screws and remove the Red chassis. The trim pots are underneath. You can't miss them. Biasing is straightforward. Getting the screw holes to line up when you put it back to gether is a bit tricky.