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stm113

Experienced
I would like to try to to get the JCM 800 in the AF2 to mimick the Platinum Mod from Voodoo amps, I played through one about 6 years ago. I just remember it having more gain than one would ever need and a lot of tight bottom end. I know the description doesn't give much info. The first obvious place to go is the Sat switch but what about the upgraded transformer? From what I understand the upgraded transformer is what helps give the amp the bottom heavy and tight sound.

http://www.voodooamps.com/home/Modifications/AMPMODIFICATIONS/MarshallMods/JCM8002203/HGJoseMod2203/tabid/182/Default.aspxa

What do you guys think?
 
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B:ASSMASTER

Experienced
A JCM already is an angry-sounding amp. Adding the renown Jose Arrendendo mod makes it even meaner. This is accomplished by turning on Saturation.

(Source: @yek )

You could also check out the "Brit 800Mod" model.
 

FractalAudio

Administrator
Fractal Audio Systems
Moderator
Changing the transformer won't have that much effect. The Arredondo mod is the Sat switch. If the transformer is undermatched that would give a slightly fuller sound at high MV settings. Use Transformer Match to simulate this.

Without knowing the specifics of the mods it's hard to say. There could be feedback modifications as well.
 

zenaxe

Fractal Fanatic
One cool thing you can do to the JCM800 to make it more aggressive is move the Master volume to the post phase inverter position. You can find that one the power amp page in Axe Edit. IIRC, this is a common IRL mod for Marshalls of that era.
 

Cagey

Experienced
Changing the transformer won't have that much effect. The Arredondo mod is the Sat switch. If the transformer is undermatched that would give a slightly fuller sound at high MV settings. Use Transformer Match to simulate this.
I really appreciate it when you point out stuff like this. To hear the marketing weenies from the aftermarket transformer manufacturers, a replacement power/output transformer will convert your barely functional amp into a world-class life-changing amplifier of doom, and if you don't buy one of their wonderful parts you deserve every agonizing moment of anxiety the lack of such an incredible part will impose. Fortunately, thanks to you most of us here don't have to worry about such things.
 

Slammin Mofo

Inspired
About the transfomer impact on tone: I've seen a Dan Boul (owner of 65 amps) podcast some time ago and he has a collection of vintage transformers. He says that they "sound" better than their modern counterparts. Is he just a snake oil salesman or is there indeed some hidden mojo in older transfomers?
 

flash6969

Inspired
About the transfomer impact on tone: I've seen a Dan Boul (owner of 65 amps) podcast some time ago and he has a collection of vintage transformers. He says that they "sound" better than their modern counterparts. Is he just a snake oil salesman or is there indeed some hidden mojo in older transfomers?
"Better" is relative. Your better might not be the same as mine
 

Slammin Mofo

Inspired
"Better" is relative. Your better might not be the same as mine
That's not the meat of the matter. Cliff stated that changing the transformer doesn't have much of an effect on amp tone, yet this guy, Dan Boul, claims otherwise. Why else would he have a vintage transformer collection instead of just getting them built to spec by Mercury Magnetics or Heyboer? Maybe it's just lack of electrical theory on Dan's part? Also, I don't think he's alone in this opinion. Many amp builders place great importance on transformers.
 

Rex

Legend!
About the transfomer impact on tone: I've seen a Dan Boul (owner of 65 amps) podcast some time ago and he has a collection of vintage transformers. He says that they "sound" better than their modern counterparts. Is he just a snake oil salesman or is there indeed some hidden mojo in older transfomers?
Output transformers affect the sound in a number of ways, including saturation and impedance matching. Many older transformers were undersized, which drove them into saturation earlier. That sometimes sounded thicker and better. But there's also a heavy dose of snake oil involved, perpetuated by the fact that, when you swap transformers, there's no way to do a direct A/B comparison. And the fact that older stuff is always better because, back then, they got everything perfect on the first try, right? :)

There are parameters in Fractal Amp blocks that let you dial in saturation, impedance matching, and other transformer-related stuff—and compare them directly.
 

lqdsnddist

Axe-Master
Given the prices of Dan's amps surely he needs some mojo marketing claims to justify the cost.

That's what your getting with the vintage transformer, bragging rights, exclusivity, and placebo effect that spending a lot of money buys you
 
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