3rd Generation rebuild

[telentubes]

Inspired by others on the Forum, I've rebuilt my 50 Watt 3rd Generation to a 3rd Generation, #124, and #102 hybrid.
It's basically a low plate/high plate, with #124 for the clean channel, and #102 for the OD.
From the 3rd Generation, I retained the one relay to engage the OD (there are no other switching options), and the "Accent" switch. There is no "Pressence" pot.

Here are a few details...
I scrapped the "FET" and wired the "FET" input jack with a 22K grid resistor. The other jack has the 33K grid resistor. There is a difference, and I like them both.
130K Slope
100pf bright cap
.001 treble cap (I may mess with this some more)
10uf Cathode bypass caps in V1

Some voltages...
V1, 192/194
V2, 190/194
V3 (12AX7) 268/263
V4 and V5, 458
Dropping... 458, 440, 310, 301
Bias, 34mV

OD trimmer set at 10.2K Ohms.

I like the amp a lot more in this configuration. The clean and OD were not well matched in the original amp, for my taste, with the two channels sounding like different amps. I have the OD trimmer set quite low, so it's more like a fat clean boost with some hair if you want it. You still have the option to dial in full blown distortion if that's what you want. The amp sounds more Dumble like (to my ears) than before. Fatter, richer, more complex.

[larsvictor]

Very nice amp, Telentubes ! Any chance of hearing some sound samples ?

Lars

[telentubes]

I'm not set up to make decent sound clips at this point, but maybe some day.

[martin manning]

Nice rehab! I'm for calling this hybrid a "Lojai," and it makes a lot of sense. OD trimmer is at 10k2 ohms, I guess? That's around half of the usual drive level onto the OD section, but then you have the high Ra.

[telentubes]

Good catch Martin. I'll change that.
"Lojai". That's good.
Did I tell you that before our recent move to Washington state, we were on the coast in California, about 20 miles west of Ojai, where Robben and Anne Ford live. We got to see Robben perform a few times locally, and I went to one of his guitar clinics in Ojai. I figured it was unlikely I'd be in a situation like that any time soon, so I ponied up. Ojai is a cool town, and the clinic was great.

[martin manning]

Fantastic! I'm with you on taking advantage of the opportunity. You'd be kicking yourself right now if you hadn't!

[Bob S]

That there is a beautiful build / rehab. Not easy.
Congrats on the "merge" - very impressive.

[telentubes]

Lowered the first stage filters back from a pair of 220ufs to a pair of 100ufs, and lowered the 10uf cathode bypass caps to 5uf in V1. Both are improvements. I prefer the 22K V1 grid to the 33K. It's more open and responsive.