The article about the design of the power suply of a 606 is edited, at last the useful comments of P..
Esmond made a revision of his FM3 Service Notes, see the blog..
Joost Plugge wrote a Weblog article about the revision and upgrade of the Quad 520f professional amp..
New items concerning the Quad 510 amplifiers. There are two versions of the 510 circuit, the first i..