Hi folks I'm new on board but have been around a bit since the days I bought and stupidly sold an old Marshall 50 on an excellent percentage from an advert in Melody Maker - bought for £50, sold for £80... why did it have those funny bottle-shaped valves in it? They're still in my spares box... another Marshall 50 and a Geloso 100W valve PA amp also passed through my hands back in the day; then I got an HH VS100 Musician Reverb "valve sound" solid-state amp for my 21st birthday. Since then I spent xx years with my HH until my younger son bought a dodgy TSL100 head, you know, the ones that keep blowing the EL34 nearest the end of the chassis. I did some mods on that to stop the leakage that causes the runaway but basically the Issue 1 PCB is rubbish and still noisy and I should have replaced it 10 years ago when it was worthwhile. Still, my son gigged it for a while as a 50W with half the tubes in it until he bought his Blackstar. Then my older son told me a colleague was throwing away a JTM60 that kept cutting out and was too loud for his bedroom so I picked it up, replaced the Dali-esque ECC83 valve bases with ceramic ones, put a jumper cable between the serial FX out and in and have used that as my gigging amp for the last few years (I did give his colleague a few quid as a thank you). Not much going on this year so it's hardly been turned on, but when I fired it up last week I found it humming a fair bit. Oscilloscope (I'm an electronic engineer by training, network designer by profession) shows at least 15V lumps on the first smoothing cap so.. time to recap. While it's in pieces, what else should I do? Googled a bit and here I am thanks to the excellent JTM60 mods thread. Bigger heater supply smoothing caps, fans, vents? Clip out the clipping diodes? Plenty to think about. New/different/gold plated FX jack sockets (what happened to jack sockets with proper contacts on them?) So there you are. I live in the south of England and was playing in a soul covers band for the last few years until Covid; before that I was playing classic rock covers for 8 years after a long hiatus. Just recently I've been using JamKazam with some bandmates to keep things ticking over.
Welcome to the forum. I love the versatile JTM60/JCM600 series. On my JCM602, I recently lifted one leg of C105, the linking cap for the diode-clipping circuit, and got rid of that horrible fizz in the OD channel. Rock on . . .
