JCM800 2203 Hermansson 5-Stage

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dorrisant
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JCM800 2203 Hermansson 5-Stage

Post by dorrisant »

I want one... Or a schematic. Either way, killing it, right?!? I hate the distorted chatter over the top of his videos, but I'm assuming it is not like that in the room. Anyone have clues about his topology? Miles...? bepone...?

Also, dude! No PPE?

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xtian
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Re: JCM800 2203 Hermansson 5-Stage

Post by xtian »

Wow, I guess he left in the treble peaker and bright caps. Super stringy. But yeah, a beast!
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Reeltarded
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Re: JCM800 2203 Hermansson 5-Stage

Post by Reeltarded »

Multiple gain controls. What amp is it? I didn't look.

1 2 3 4 5 CF.. in this sort of thing 1 and 2 get controls and 3 or 4 also, choosing which is a matter of choice with 3 being capable of not melting so much and 4 being pretty heavy sounding before it even touches 5 because 3 is WFO.

1 is probably close to center biased and the --> stages probably have similar to SLO (1u) and alot of cold selections up to the CF driving stage. It's pretty good. I think I have the schematic for probably that very circuit but it will take some looking.

I bet Google knows.

Based on a better recording, if you know what Atomica is.. that is what this is, but two more cold stages.
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Reeltarded
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Re: JCM800 2203 Hermansson 5-Stage

Post by Reeltarded »

Here is a decent start.

Build a stock 800 but put .047h output couplers and you need to decide how big the 10k cathode should be at the end when you hear it. 22k with 10u over will rock but maybe a little too much.

Add a tube in front. Both stages get gain controls. 1k5/10u 1st then stage 2 is where the majority of flavor happens. I bet 2k7 and .68u spund pretty good.

After the second gain stage, Signal splitter 50/50. Do it like Marshall 470ks. Over the signal side, and I can't emphasize this enough, 2200p peaker.

That SOUND is the 2200p peaker, everything else just decides which side of Hell the demon came from.
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dorrisant
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Re: JCM800 2203 Hermansson 5-Stage

Post by dorrisant »

Reeltarded wrote: Fri Oct 13, 2023 12:49 am Here is a decent start.

Build a stock 800 but put .047h output couplers and you need to decide how big the 10k cathode should be at the end when you hear it. 22k with 10u over will rock but maybe a little too much.

Add a tube in front. Both stages get gain controls. 1k5/10u 1st then stage 2 is where the majority of flavor happens. I bet 2k7 and .68u spund pretty good.

After the second gain stage, Signal splitter 50/50. Do it like Marshall 470ks. Over the signal side, and I can't emphasize this enough, 2200p peaker.

That SOUND is the 2200p peaker, everything else just decides which side of Hell the demon came from.
Love this!
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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Reeltarded
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Re: JCM800 2203 Hermansson 5-Stage

Post by Reeltarded »

May Mark Cameron have mercy on our souls.

Atomica Forever
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neskor
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Re: JCM800 2203 Hermansson 5-Stage

Post by neskor »

maybe something like this
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Reeltarded
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Re: JCM800 2203 Hermansson 5-Stage

Post by Reeltarded »

Easier to imagine as a cascaded plexi with a repeat of the first two stages.
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bepone
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Re: JCM800 2203 Hermansson 5-Stage

Post by bepone »

dorrisant wrote: Thu Oct 12, 2023 8:14 pm I want one... Or a schematic. Either way, killing it, right?!? I hate the distorted chatter over the top of his videos, but I'm assuming it is not like that in the room. Anyone have clues about his topology? Miles...? bepone...?

Also, dude! No PPE?

i know who is the guy, maybe you can contact him, it is selling vintage resistors😀
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Re: JCM800 2203 Hermansson 5-Stage

Post by bepone »

now i have listen ,
i have constructed similar amp 13 yrs ago, remainds me on Soldano SLO iteration of the amp


here are used self constructed toroids for main and output, with good results,

then you can move from SLO stock 2k7, 10k, 39k in cathodes to 1k5 like fender to increase gain, you will get this kind of distortion :P
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