All new Ground Zero “Add-a-stage” PCB - add a gain stage to your amp the easy and clean way

psychodave said:
I like it, but have you considered adding the tube to the board, but NOT having to cut up the amp?
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You mean like this? I did it a couple years ago.

This JMP had 4 gain stages, an fx loop and a full mod. With not one extra hole drilled in the entire amp.

Really, I think it’s more convenient having access to the tube without pulling the chassis. But if there was enough demand for it, I’d consider making it.

I have another really cool PCB design coming soon. It will require drilling but it’ll be worth it.
 

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I don't mind an extra preamp tube hole as long as it's spaced like the originals. Many factory Marshalls came with a 4th hole already, but covered with a plate. So I don't see the big deal. These chassis were most likely manufactured so they could accommodate different circuits, like the trem model.

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Following for your mods.. I don't think I can squeeze this thing into a weber 1987x small box but if you do a 2204 at some point, I have a ton of real estate in those. Maybe the ultimate challenge... add this to a Bugera 1960 infinium?? It has the RR cascade mod already, would be cool to add this to it.
 
Kapo_Polenton said:
Following for your mods.. I don't think I can squeeze this thing into a weber 1987x small box but if you do a 2204 at some point, I have a ton of real estate in those. Maybe the ultimate challenge... add this to a Bugera 1960 infinium?? It has the RR cascade mod already, would be cool to add this to it.
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I got one into a 1987. It’s tight but works. Tube comes out the side.

The possibilities are going to be pretty endless with this one. It’ll also work great in a stock super lead to make a Jose circuit. Instant extra gain stage in front of a stock super lead.
 

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RedPlated said:
I got one into a 1987. It’s tight but works. Tube comes out the side.

The possibilities are going to be pretty endless with this one. It’ll also work great in a stock super lead to make a Jose circuit. Instant extra gain stage in front of a stock super lead.
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Well done! Didn't think of that but that is actually a great idea. I have a bit for making a hole in chassis and this gives the option of a quick(er) tube swap if needed. The amp being a Weber, a little swiss cheese in the side of the chassis won't devalue the thing.
 
Could that come without the tube socket mounted?
I have a punch that would make a clean hole and mount the socket nicer, help my OCD not go crazy.
Would it work for my Metro JTM45?
If so, Ill purchase one.
 
dcburn said:
So cool!
Can I just ask, do you think there would be any noise issues removing the tube socket from the board and using wire from chassis to board?
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Should be totally fine running he tube socket as flying lead instead of board mounted.
 
rottingcorpse said:
Man...I love this forum.
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This might be the new Metro forum! I love this geek shit too because I love tweaking my stuff. I remember being so proud of myself when i first modded my Laney Pro tubes PCB to bypass the gain mods to get a straight 2204. I then gutted it and rebuilt it into a Caswell 39 sort of deal. Eventually settled on a 2204 with a few plexi tweaks. It sounds great. But I'm always game to try more stuff out.
 
RedPlated said:
Yes I plan to offer them as loaded or unloaded.

This one is designed to only use one triode. It would be nice to have the option of using both sides of the tube, but then the board becomes bigger and more complex.

I think the most common application is adding one additional stage. Not many designs add two additional stages. Maybe if there was enough demand I’d consider making one.
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This might be dumb as all get out to ask....

Could you cascade the add on board into another add on board and go from 3 gain stages to 5?
 
I think this is totally badass in case I forget to mention it. I really want to mod my Windsor and add one of these also. Cause fuck it that’s why…..
 
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