Without further adieu, here is progress on my build. Looking back over the past few days, I took far fewer photos than I would have liked. I had some challenges - first with the finger joints on the cabinet; I built a jig for the router table, then destroyed my 1/2" upcut spiral bit making test cuts. So I re-worked the jig for table saw set-up with a dado blade. That took a while, then took a number of test cuts to get the spacing right. That took me until well after midnight on Friday. Finally cut the fingers in the boards I glued up, only to find they were just slightly too tight so I had to re-work things to get them to fit, then had to deal with some tear-out issues.... once that was done, I enlisted the help of my lovely wife to spread glue across all the fingers and get it into the clamps:
Then while the glue was setting, it was back to soldering. Finished it all up in about an hour, plugged it in and started checking voltages. Heater voltages checked out, very slightly high but probably acceptable. The rectifier voltage a bit low, but probably acceptable. No smoke, fuse didn't blow... all good. So I wired up the speaker, plugged in the tubes and powered it back on again:
Tubes started to glow. Kept checking voltages... again, a few seemed to be a bit on the low side, but I don't think it is catastrophic. Checked the MOSFET, working just fine; voltage came up as I turned it up. Turned up the volume, very slight hum coming from the speaker with my ear nearly right on the cone... almost not detectable. Time to plug in a guitar.... strummed the strings and NOTHING!! Oh my.... what is wrong.... spent the next 2 hours double-checking everything, wondering if I wired the speaker wrong, etc. Finally noticed that I hooked up the shielded wire from the gain pot to the pre-amp in the wrong spot. 5 minutes later had that fixed and guess what..... IT'S ALIVE!!!!!!!
I played it like this for a few minutes on Saturday night out in the shop, then went to bed:
Ok, Sunday...... lots to do, I want to test-fit this in the cabinet before evening rolls around. And I was encouraged enough to get the camera back out and do a better job documenting it.
I milled up some pine for the speaker baffle and glued up the panel:
Then set about cutting the speaker hole (using my router):
Test-fit the speaker...
And put it into the cabinet. Then fit the amp into place:
I ad-lib'd a little bit on the front; taking a bit of 'artistic licence'.....
Welcome to the stable, little Tramp! (btw, I built both guitars flanking the amp, along with the one behind it):
Still a bit of work ahead of me... need to round over all the edges, final sanding and finishing. I needed another can of sealer, which shipped out today. Maybe over the weekend.
Now about those voltages...... well, maybe it has fixed itself:
Input is exactly 120 VAC
Across rectifier pins: 630 VAC
First 50 uF filter cap: 414 VDC
33uF cap: 335 V
But then, over to the pre-amp side:
Pin 1: 198 V (target is 203; close enough??)
Pin 6: 178 V (target is 191)
I have a 6v6 tube in and have the bias set appropriately. VRM is all the way up. I have 407V coming off the 50uF filter caps. Set to Tweed, Thin.
Regardless, it sounds amazing. Really happy with this build. I have to admit, I was very apprehensive at the start. Other than wiring up the guitars I built and the odd repair around the house, I really haven't done much soldering. I've never worked with resistors and capacitors. The first couple night I worked on this I was completely overwhelmed. But, I received great support from Stephen at Trinity along the way and great resources available through this forum. Very pleased with the outcome - extremely rewarding.
Will post completed cab once the finish is one... and the grille cloth.
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