“This has been my first start to finish amp build and as I intend to use the amp with a bass I made a few changes from the start. The preamp is as per your design but with a GT 5751 and a 22uF cap on the cathode of the first gain stage. I also added the tone control.”The power tube is a 6550, I have added adjustable bias and used a Hammond output transformer with a reflected impedance of 2.5k and a master volume. On the power supply I removed D5 and changed the first two smoothing caps to 47uF/450V. Every thing worked perfectly first time.
“Super quiet and fantastic tone. A testament to the best build guide of any of the amp kits I looked at. It took me about 8 hours start to finish including painting the face plate, a trip to Maplins to get a couple of test points for the bias adjustment and numerous cups of coffee. I am very proud of this little lady, im guna re-name mine the WF-65.5”