Hi guys Decided to build myself an amp. The 5F6a bassman. Have looked at a few layouts on the web and just have a few questions if anyone will be nice enough to help me out. Im a carpenter by trade and will be building a super nice cab when its done so will post pics along the way! Ive posted the layout pic im using below. questions: Are the diodes and cap needed on the rectifier tube? if so what sort of diodes are they? The 25k bias pot with 22k resistor in series is shown here. Can i directly replace those with a 50k bias pot ans 15k resistor?? The filter caps show 2x22uf and 2x20uf, some layouts show 4x20uf...will there be any difference??