I had this Fender Princeton clone I built last winter that started making this weird humming noise after about 3 months. I checked every solder joint with my magnifying lamp, swapped the filter caps, even reflowed the whole power section. Nothing. I was about to rip out the whole board when my buddy at the guitar shop said try swapping V1 and V2 tubes. I thought it was a joke but figured why not. Took me 30 seconds and the hum dropped by like 80%. Apparently one of my new JJ tubes had a microphonic issue right out of the box. Has anyone else had new production tubes that were duds like this?
How do these high end builders charge $2,000 plus for an amp that has cold solder joints and shaky bias straight off the floor, has anyone else walked into a store and seen brand new gear that was clearly slapped together?
Met a guy named Mike at Carter Vintage on a trip last month, been fixing amps for 40 years. I was showing him my first scratch build, a little 5F1 clone, and he just nodded and said 'you can't tune a hot rod by reading the manual.' Hit different because I'd been obsessing over schematic specs and not actually listening to the amp. Anyone else ever had some old timer drop a truth bomb like that?
There was a guy selling a bunch of vintage radio gear from the 50s, and mixed in were these hand-drawn amp plans for a Fenderish circuit. I bought the whole pile for $15. Has anyone else stumbled on old schematics at random places like that?
I always thought variacs were overkill for powering up a new build, just flip the switch and hope. Then my last 5F1 build started smoking on the first power up and I lost a $40 output transformer. Is a variac actually necessary or did I just get unlucky?
I've been building little 5-watt guitar amps for a couple years now, just as a hobby. Last week I finally bought one of those cheap infrared thermometer guns off Amazon for like 15 bucks. Decided to check the temperature on my power tubes while it was cranked up. Turns out my EL84s were hitting almost 210 degrees on the glass. I looked it up on a few amp forums and apparently 150-170 is the normal range for those tubes. So I've been cooking them extra hot this whole time without knowing. My bias was probably off or my plate voltage was too high, I'm still figuring out which. Has anyone else had a similar scare with tube temps after finally getting a thermometer?