After faffing about with a Chinese tube amp for a while, and increasing my understanding about how amps work, I decided to build a 5F2a Princeton, from a kit supplied by Modulus Amps. The build went well, and was completed over a period of three days, with the amp working first time. (No smoke, sparks or explosions!) The build was done to the Modulus layout, with the exception of the 68K Grid stopper resistors, which were changed to metal film, mounted on the input jacks and connected to the preamp tube by shielded cable. (Shield grounded at the jack end) I read somewhere that this was a good idea! The amp is temporarily housed in a cab with a 12” speaker. I’ll get a cab built for it soon, but it may get a 10” speaker. Not decided yet. I’m currently trying to figure out if a slab of hardwood I have will be big enough for the box. Cardboard templates being produced. Only minor issue is a slight amount of hum, so I may do some wiring adjustments to see if it makes any difference.