JC50H Modded for EL34s??
Moderators: greatmutah, GuitarBilly
JC50H Modded for EL34s??
Hey guys, I've gotten many cool tips here, so thanks for the helpful info. I just picked up a JC50H, I'm currently working on getting all new tubes for it. My only concern is possibly the 6L6s not taking my fuzz faces very well. I have , and love a JC22h that my fuzz pedals sound great though. Anyway, I know some guys mod these to take EL34s. I'm just curious if any of you guys have any experience with this , and what you thought about the results? Also, I would love to hear from any of you that use the 6L6s and fuzz, and your thoughts. Thanks a bunch guys!
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Re: JC50H Modded for EL34s??
Haven't done it yet, but planning to later this year. I know the SGRs need to be upgraded, not entirely sure (or at least don't remember) what else needs to be done.
Would love to hear clips of the differences between the two (6L6 vs EL34) if you do the switch!
Make sure you check out the main JCA thread (see my signature below)
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Would love to hear clips of the differences between the two (6L6 vs EL34) if you do the switch!
Make sure you check out the main JCA thread (see my signature below)

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Re: JC50H Modded for EL34s??
billyg121 wrote:Hey guys, I've gotten many cool tips here, so thanks for the helpful info. I just picked up a JC50H, I'm currently working on getting all new tubes for it. My only concern is possibly the 6L6s not taking my fuzz faces very well. I have , and love a JC22h that my fuzz pedals sound great though. Anyway, I know some guys mod these to take EL34s. I'm just curious if any of you guys have any experience with this , and what you thought about the results? Also, I would love to hear from any of you that use the 6L6s and fuzz, and your thoughts. Thanks a bunch guys!
I have a JCA100. Its had some mods done, depth mod, clean channel mod, some other stuff. (I didn't do any of it.) I don't think the 6L6s will be a problem with your Fuzz Face. My VTM120 is 6L6 based and takes fuzz like a champ. Whether dialed back classic fuzz tones or DESTROY THE WORLD full bore fuzz.
The JCA100 doesn't really like the "Destroy the world" type stuff and I didn't even bother messing around with my fuzz on the OD channel I like its tone too much.

I'm just wondering, why do you think the 6L6s wouldn't take your FF well?
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Amps: ACC150 (x2), Peavey VTM120, JCM600, Peavey Bravo, Yamaha THR5
Cabs: Mesa Halfback 2x12, Peavey 1810, Randall RS125CX
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Re: JC50H Modded for EL34s??
Most of the 6L6 amps ive played in the past, suffer a bit with a fuzz face because of the added roundness in the low end with that tube. I havent really tried to many different EL34 amps, but it seems they push the mids up just a bit and sound great with a fuzz face. Yep, im just going for vintage hendrixy type stuff with the fuzz. again thanks for any thoughts. I will also check out the JC Lounge.
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Re: JC50H Modded for EL34s??
billyg121 wrote:Most of the 6L6 amps ive played in the past, suffer a bit with a fuzz face because of the added roundness in the low end with that tube. I havent really tried to many different EL34 amps, but it seems they push the mids up just a bit and sound great with a fuzz face. Yep, im just going for vintage hendrixy type stuff with the fuzz. again thanks for any thoughts. I will also check out the JC Lounge.
Ahhh, I understand.

Good luck figuring out what you want and welcome to the board!

Main Guitars: Gibson SG Classic, Agile AL3100, Fender Blacktop Telecaster
Amps: ACC150 (x2), Peavey VTM120, JCM600, Peavey Bravo, Yamaha THR5
Cabs: Mesa Halfback 2x12, Peavey 1810, Randall RS125CX
Amps: ACC150 (x2), Peavey VTM120, JCM600, Peavey Bravo, Yamaha THR5
Cabs: Mesa Halfback 2x12, Peavey 1810, Randall RS125CX
Rampage wrote:Oh, you can't play guitar because of your cats? What's next, you don't have sex with your wife because your vagina is acting up?
K-Bizzle wrote:There comes a point in every young mans life when he forsakes the skittles and mountain dew of his childhood for the beer and reese's of manhood.
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Re: JC50H Modded for EL34s??
I believe the one or more screen grid resistors need a swap but, IIRC, the tranny can handle the added heater current draw.
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Re: JC50H Modded for EL34s??
It's all the screen grid resistors (1 per power tube - 2 for the 50 and 4 for the 100). I keep reading that upgrading the SGRs is something that's a good idea anyway, and yes to the transformer capacity - this seems to have been verified by Mike Soldano, who did a video with Doug White where they performed this conversion. Again, see the links in the main JCA thread for more info (and the link to this video), which you can get to by clicking the link in my signature below.
Anxious to hear a review and clip of the results!
Anxious to hear a review and clip of the results!
Co-founder of the Jet Setters 2.0 (Jet ★ City Lounge Redux)
Gear
DIY
Gear
- CEOwLP (Sig T), Carvin DC135, Westone Spectrum SX (guitar) & GT (bass), Squier strat
- '66 Bassman, '61 Magnatone, Mark III, 1960AX, homebrew 2x12 (C90 / EVM12L Thiele), HX Stomp, JCA50H
- PLX GABion, SD-1, TS9, Crybaby, MXR108, Algal clone, Carbon Copy deluxe
DIY
- New workshop - Teh GRIMESHOP™!
- Bassman overhaul - G-MAN
- Home studio - GRIMESPACE Sound Lab!
Ostinato Rubato wrote:"That's the second boomery bro on this forum I've helped seduce to the greenside."
"Slow and steady gets to **** again eventually"
Re: JC50H Modded for EL34s??
Also, make sure pin 1 on the power tube sockets is grounded.
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