Build in progress

[plook]

I think this looks great. Love the use of the tag board on the EL84s toi avoid the 'floating' resistors and the board around the 12AX7 tubes. Really impressive and i look forward to hearing about the results.

[Bob S]

After a long layoff due to a heavy workload, I'm back to making smoke with my trusty old Weller.
I want to try this before I get into what RJ & the guys are up to with the pcb
design. That looks very promising.
I moved stuff around - again... Still not happy with the layout.
The soldering looks awful - the same turrets that have been a pia to a lot of the guys.
Should be firing her up tomorrow - hopefully not a howling mess.
Wish me luck.

[martin manning]

Looking good, Bob! That PCB Express thread has got me doodling an eyelet board layout along these lines. Time to get some parts and get it moving!

[M Fowler]

Bob that looks damn good, me likes

Mark

[RJ Guitars]

I like the way that is going... a similar theme to my PCB work but you got some very good ideas in the way you address the component lead length and orientation while leaving the tubes in the more familiar location. I think this is going to be a very cool amp and should help with the stability issues.

Those turrets are from the devil himself... if they are the same ones that AES sells with their perf board. You'll know'em right away because they are made from brittle metal and are hard to swedge without splitting them and it takes a flame thrower to heat them enough to make solder stick. The good news is that if you get them hot enough to tin them then they are a bit more friendly and useable after that.

Nice project and I'll look forward to your progress reports and final results.

rj

[RJ Guitars]

Early after I fell under the spell of DIY guitar amp building, one of my tube amp mentors asked me about my favorite amp(s) and I showed him my Fender Pro Junior - simple, small, and great tone. The only thing I didn't like about it was that it had some hum. He bought a few of them off of EBAY and rebuilt them, then one day he asked for mine. He said he could improve it and teach me some more critical skills for amp building. When he brought back a box of pieces, all the critical lessons were there for me to do something with, a DIY education in a box. He was really a tube HiFi fanatic and had this belief that if he could mount all the components from the board to the tube socket using the shortest lead lengths possible, he could eliminate noise and tone loss issues... I think this is a Fender Princeton circuit all on one board, feeding a pair of EL84 output tubes.

Sadly this board has sat waiting for me to put the amp back together for the past several years. I did listen to what he said and applied some of those ideas to my builds, my PCB Express was a
nudge that direction, but not a full commitment to it.

The featured build in this thread takes that concept to the ultimate form without holding on to the history and warnings not to mess with this circuit... looking forward to seeing how this turns out, I have high hopes!

Maybe this will be enough inspiration for me to put my Pro Junior back together as well.

rj

[M Fowler]

When does the Pro Junior SSS kit come out

I like that type of construction rj it would work great for a Overdrive Reverb or SSS type build.

Mark

[Bob S]

Finally got back from California last night & got some time to tinker with her a little more.
310V B+, Parallel V1 & Presonance work good.
Still have to find a spot for the B+ voltage control.
No hum & very low hiss right out of the box.
Sounds like a Liverpool - maybe not as close to the edge of stability.
Volume / Gain works well - I can dime this thing - can't do that with my traditional clone.
Maybe I'll kick the gain up a notch at a later date (never thought I would say that about a liverpool).
Think I'll get to know her first.
Thanks to all you guys who have helped.
Big thanks to Mike (ampmike) for the cab. Wish I could get a decent pic, it is stunning.
Now - what next?
Bob

[RJ Guitars]

That is so cool. This lends more evidence to the thought that the stability of the Wreck circuits can be managed by a little strategic component placement. The theory for that has been recognized for a while but these results are really telling a great story. Nice work! rj

[Bob S]

Finished - for now anyway.
Thought I'd post some final pics with her finished up.
B+ voltage control scaling the whole amp - me likes much.
Presonance much more versatile than the original Presence.
TMB work good - I paralleled the pots with resistors to knock the pot value down. Changing a pot on this would not be fun...
Sounds very good with a strat.
Now to put some burn in hours on her.

[Reeltarded]

Very cool. I don't know what is possible until I see it, you know?

I would have named it Charlene.

Can we hear it?

[Structo]

Hey Bob the "Bitch" looks great.

Some day I want to try some power scaling via VVR probably.

Beautiful cab as well.

Congrats on a cool amp.