Just finished this today. It's kind of an AC15, using a Mojo chassis, board and faceplates, some old Matchless transformers from West Labs and a Mercury Magnetics Vox AC15 OT. When built stock it was way too bassy. Maybe the Mojo transformers don't produce as much low end as the trannies I used? I dunno. So I have reduced some of the coupling cap values and used a 1µF cathode cap on V1 - that really helped get the amp into the guitar range.
Playing around with power tube cathode resistors and doing lots of maths got me biased to around 100% plate dissipation, so the driven sounds are glorious. Very Brian May at actually reasonable volumes. It's loud, but I reckon a fair few players wouldn't find it too loud for their gig. Anyway it works beautifully with a decent OD too.
The stock chassis has the rectifier hole punched for an EZ81 because the same chassis is used for their Marshall 18W kit. So I found an inexpensive hole punch on Ebay and made the hole big enough for a GZ34. It was easy enough to do, too. A decent GZ34 is easier to find than an EZ81 and is probably more authentic too.
I love making these things.
Playing around with power tube cathode resistors and doing lots of maths got me biased to around 100% plate dissipation, so the driven sounds are glorious. Very Brian May at actually reasonable volumes. It's loud, but I reckon a fair few players wouldn't find it too loud for their gig. Anyway it works beautifully with a decent OD too.
The stock chassis has the rectifier hole punched for an EZ81 because the same chassis is used for their Marshall 18W kit. So I found an inexpensive hole punch on Ebay and made the hole big enough for a GZ34. It was easy enough to do, too. A decent GZ34 is easier to find than an EZ81 and is probably more authentic too.
I love making these things.