5E8A Amp Clone Build

bluesky636

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Just completed my latest and last amp build (I'm 68 years old and have built a Fender 5F6A, Fender 5F1, Trainwreck Express, and heavily modified a Fender Blues Deluxe Reissue, and Fender Champion 600 Reissue. I think that's enough.), a Fender 5E8A head.

All my builds have been based on Weber's kits to which I have added my own little tweaks. Note that the Weber kits do not come with instructions, only a schematic and wiring diagram. You do need to know what you are doing. I have a BSEE (1976, the last year that vacuum tubes were part of the curriculum) and learned to solder while in college.

The head version of the Weber 5E8A is unusual in that the chassis is the same chassis as used in their 2x12 combo cabinet kit. As a result, when built as a head the tubes sit parallel to the bottom of the head instead of hanging vertically.

The head is then plugged into a Crate 4x12 cabinet loaded with 16 ohm Celestion G12M-25 reissues. The cab is wired to allow a choice of stereo 8 ohms, mono 4 ohms, or mono 16 ohms. The output transformer of the 5E8A is 4 ohms.

The power transformer is wired for 120 VAC input (as are all my amps). My wall outlets measure between 122 and 124 VAC so I use a AmpRX Backline Power Station to bring the voltage down to about 118 VAC. Power tubes (JJ 6L6GCs) are biased about 60% (still tweaking the bias). Preamp tubes are JJ 12AX7s (2) and JJ 12AX7s for the voltage amp and phase inverter. Weber Copper Cap WU4GBs (2) are the rectifiers. I've added a bias adjustment pot to the front panel to be used with a dual bias probe.

That's about it for technical details so here are some photos. I have ordered name and serial number plates for front and back. Hope you like.

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bluesky636

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Looks like you had a lot of fun! Might be a good idea to trim back the tolex around the power tubes.
Thanks.

The picture makes it look worse than it actually is. There is about 1/4" between the tolex and the tip of the power tubes and they only overhang the tolex by a small amount. I've had the amp on for well over an hour with no problems.
 

ac/dcfan87

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So this is a Tweed Twin? Is that kind of like the Tweed Deluxe 5E3 but a big boy variant? I am curious.
 

D'tar

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There's more to it than that as noted in the link I posted.
Yep, sure there is! I didnt notice the link on my phone. ++ fixed bias, NFB, not a whole lot in common w the 5e3 when you itemize things.
 

D'tar

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Congrats on your new amp! Enjoy
 
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CB91710

Not Michael Sankar
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Yep, sure there is! I didnt notice the link on my phone. ++ fixed bias, NFB, not a whole lot in common w the 5e3 when you itemize things.
Yep... The Super may be closer to the 5E3, but even then, it's not the same.

I've got a bit of a dilemma on something I'd like to build.
I have an old Stage Lead 212.
Thing weighs a ton, but the cabinet is in perfect shape *and* is the same size as the Twin Reverb cabinet.
I'd like to build a tube amp... but I absolutely positively do not need a 100w amp.
I don't even need a 50w amp.
So I would consider something that used a pair of 6V6s... pop in a pair of Neo Creambacks to keep the weight down.

But I would want to use something like the Mojotone Twin chassis, but none of the 6V6 Fender designs have the same control/input layout as the big Twin.
One option would be to use the Twin kit, but drop one tube pair and go with 6V6... but then the outputs would be hit with the higher voltage of the Twin's PT... and nothing would draw enough current to introduce any sag.
Base it on the Twin, but go with the OT and PT from a smaller amp? That would work, but now the cost has increased to the point that I may as well just buy a 5E3 kit and shitcan the old Stage Lead. It sure isn't worth what it would cost to ship it anywhere.
 

D'tar

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Yep... The Super may be closer to the 5E3, but even then, it's not the same.

I've got a bit of a dilemma on something I'd like to build.
I have an old Stage Lead 212.
Thing weighs a ton, but the cabinet is in perfect shape *and* is the same size as the Twin Reverb cabinet.
I'd like to build a tube amp... but I absolutely positively do not need a 100w amp.
I don't even need a 50w amp.
So I would consider something that used a pair of 6V6s... pop in a pair of Neo Creambacks to keep the weight down.

But I would want to use something like the Mojotone Twin chassis, but none of the 6V6 Fender designs have the same control/input layout as the big Twin.
One option would be to use the Twin kit, but drop one tube pair and go with 6V6... but then the outputs would be hit with the higher voltage of the Twin's PT... and nothing would draw enough current to introduce any sag.
Base it on the Twin, but go with the OT and PT from a smaller amp? That would work, but now the cost has increased to the point that I may as well just buy a 5E3 kit and shitcan the old Stage Lead. It sure isn't worth what it would cost to ship it anywhere.
Hey CB, maybe start a thread.... "WTF can I do with this?!".... lol
If you are adventurous, you can scale down just about any circuit. Have you seen Robinettes micro circuits? That 1st watt does a lot of work! A clever faceplate can utilize the holes you need and cover those you dont.

 
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bluesky636

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Yep... The Super may be closer to the 5E3, but even then, it's not the same.

I've got a bit of a dilemma on something I'd like to build.
I have an old Stage Lead 212.
Thing weighs a ton, but the cabinet is in perfect shape *and* is the same size as the Twin Reverb cabinet.
I'd like to build a tube amp... but I absolutely positively do not need a 100w amp.
I don't even need a 50w amp.
So I would consider something that used a pair of 6V6s... pop in a pair of Neo Creambacks to keep the weight down.

But I would want to use something like the Mojotone Twin chassis, but none of the 6V6 Fender designs have the same control/input layout as the big Twin.
One option would be to use the Twin kit, but drop one tube pair and go with 6V6... but then the outputs would be hit with the higher voltage of the Twin's PT... and nothing would draw enough current to introduce any sag.
Base it on the Twin, but go with the OT and PT from a smaller amp? That would work, but now the cost has increased to the point that I may as well just buy a 5E3 kit and shitcan the old Stage Lead. It sure isn't worth what it would cost to ship it anywhere.
Yes. Please start your own thread instead of hijacking mine. Thank you.
 

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