Carvin X100B 6L6 ECC803S V1 Option

Most of these amps are fixed bias but over the years many have been modded to be adjustable bias.

If your amp is adjustable bias then all you need to check and adjust the bias is a Multimeter if you use the Carvin method. For more accuracy you can also use a bias probe and a Multimeter, or our all-in-one Eurotubes "Pro One" bias probe that reads both the plate current and the plate voltage simultaneously. These are available under the "Related Products" tab.

You can use our Carvin bias video for reference which we did on a V3.

The video below explains the difference between bias probe types.