Enter The Twi-Luxe 5E3-A?

The Ballzz

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Hey Folks,
I've been researching/pondering this one for a while! :hmm: I call it the Twi-Luxe, 5E3-A, as it's an incestuous marriage of a 5E8-A to a 5E3 power section. :wow: As can be seen, this is just the rough plan and I've not yet worked out the dropping string to achieve the voltage targets shown and am not yet sure of the choke. I'm a big boy and welcome being slapped around like a red headed step child on this!

It's gonna be in a JCM800 style chassis and want to use the listed iron that I already have on hand. The OT is from Musical Power Supplies, with a choice of 6K6 or 8K primary and 4/8/16Ω secondary taps. As per my convention, my chosen component and voltage values are in blue and all else is direct from the Fender schematics. Research and assumptions indicate that this will be a smokin' little low watt monster with oodles of character and tonal complexity. I plan to try driving all four input triodes in parallel, not so much for gain, but for fatness and tonal depth and touch sensitivity. This is my first attempt at design and hope for some spirited comments and assistance.

Thanx 4 Lookin'
Gene

Twi-Luxe-5E3-A-Schematic.jpg
 

LPTDMSV

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I would say yes yes yes for valve rectification, cathode bias and the phase splitter arrangement. I presume the tone stack is one you know and like.

I can't comment from experience, though, as to the benefits of retaining 4x inputs or paralleling them all up, when you're only likely to ever use one . . ? Lower input impedance from going parallel is going to make the amp react more to different pickups and favour low impedance ones?? Just thinking aloud here :)
 

The Ballzz

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For those who may not read "schematic-ese" this is a 5E8-A Low Power Tweed Twin preamp, driving into a cathode bias, 6V6, 13 watt, 5E3 Tweed Deluxe power section! FWIW, the stock 5E8-A with 6L6, fixed bias would be 40-ish watts and screamin' loud when driven into it's sweet spot. At 13 watts, you can "let 'er rip" with only a tiny bit of attenuation needed occasionally, in some venues! Not shown on the schematic are the passive effects loop and master volume.

Understand, though I've built some amps, I'm not an amp builder. I am instead a lifelong, usually gigging guitarist/lead singer who is striving for that holy grail tone that blends just right with the dynamics of my voice! While I certainly realize that the audience will never notice the nuances that I stress over, the closer I get to achieving that "perfect" sound, the better I feel about what I'm doing, I feel more comfortable/creative and at the end of it all, I play and perform better. That "playing and performing better" is what the audience notices and appreciates!

Thanx 4 Checkin' In,
Gene
 

matthew bear

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Initially I had the concept backwards ( 5e3 preamp into a LP twin power amp) but I quite like the notion of this setup! :hmm:

I’m of no help here but I support your endeavor :laugh2:
 

The Ballzz

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HOLY CRAP!

There are many disparate takes on how to wire the supposedly same tone stack, once you get looking at the various kit vendors' documentation, along with original Fender documents. Heck, even Fender's layouts and schematics are not in total agreement with each other. Here is my sorta rough draft, with hopes that some folks may peruse it and pick it apart and/or point out anything I missed? And yes, I realize I've not yet shown the Presence connectio to the OT secondary, as I've not yet decided on 4, 8 or 16Ω tap.

Except for the added effects loop and master volume, it should match the above schematic. While I don't really like the caps/resistors hanging off the pots, that's the way Fender shows it and I'm a bit short on enough real estate to do it else wise!

I'm also a bit confused over what values the choke should be, given the fairly high overall current draw of the preamp section, compared to using 6V6s instead of 6L6s in this design? Also wondering if I need to think more about where I split the ground between power and preamp section? Particularly if I should put the PI on the preamp ground and how best to get a good ground to that preamp section, as I'm not certain I want to depend on the aluminum chassis.

Please forgive the crudeness of the drawing, as this is my first go-round on drawing a layout from scratch, with less than appropriate software/tools.

Thanks 4 Lookin' Folks,
Gene

Turret board blank layout .jpeg
 
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