Getting more mids from a JCM-800 preamp?

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Mark
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Re: Getting more mids from a JCM-800 preamp?

Post by Mark »

pdf64 wrote: Wed Nov 06, 2024 9:17 am
Mark wrote: Mon Oct 21, 2024 11:00 pm
Roe wrote: Mon Oct 21, 2024 4:36 pm does the presence control help?

are you looking for low or hi mids?
Thanks for your reply.
Low mids primarily, the idea is to get it to work with a Strat.
The most significant change is to get a tone control on to the bridge pickup, as per Rory Gallagher.
I did this years ago. I’m surprised Fender didn’t incorporate this in the seventies, mind you it took them forever to put a five way switch into a Strat as standard equipment.
Yours Sincerely

Mark Abbott
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Re: Getting more mids from a JCM-800 preamp?

Post by Snicksound »

Mark wrote: Mon Oct 21, 2024 11:00 pm
Roe wrote: Mon Oct 21, 2024 4:36 pm does the presence control help?

are you looking for low or hi mids?
Thanks for your reply.
Low mids primarily, the idea is to get it to work with a Strat.
For a Strat I'd day the main goal should be to reduce the high mid emphasis early in the circuit. As others have said, a 2n2 cap on the treble peaker instead of 470pF (Soldano style) would go a long way. If it has a .68uF on V2a (Cathode follower driver) then up that to a multiple uF cap.

I'd probably leave the .68uF on the input stage, but it's worth experimenting with a slightly bigger cap (1 to 2.2uF).

If the first coupling cap is smaller than 22nF (some are), up that to 22nF.

A depth control is typically used to increase low end, but it also has a big effect on low mids. Turning down Bass but increasing Depth gives a nice full tone.
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Reeltarded
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Re: Getting more mids from a JCM-800 preamp?

Post by Reeltarded »

Use a variable slope control and lower treble setting when at 68-82k. 100k pot with a 33k stop gets you from annoying JMP to almost Dumble.

Counter-intuitive, but righteous. 82k is my favorite slope value.

Parallel mid control divorces the interaction of the BT controls. The bass @7 and the mids where it sounds great. That might end at treble on 3-4 and pres in the middle or lower. It is also a bit magical.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
Mark
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Re: Getting more mids from a JCM-800 preamp?

Post by Mark »

Reeltarded wrote: Sun Feb 02, 2025 6:06 pm Use a variable slope control and lower treble setting when at 68-82k. 100k pot with a 33k stop gets you from annoying JMP to almost Dumble.

Counter-intuitive, but righteous. 82k is my favorite slope value.

Parallel mid control divorces the interaction of the BT controls. The bass @7 and the mids where it sounds great. That might end at treble on 3-4 and pres in the middle or lower. It is also a bit magical.
Thanks for your advice Miles, I assume there is an increase in gain as well?
Yours Sincerely

Mark Abbott
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Reeltarded
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Re: Getting more mids from a JCM-800 preamp?

Post by Reeltarded »

Not real. Only because of the interaction vs new curve you set with controls.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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