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Hoffman Amps Forum image Author Topic: Plexi + JCM800 2 channel  (Read 2121 times)

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Offline dennyg

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Plexi + JCM800 2 channel
« on: November 25, 2017, 09:45:59 am »
I'd like to build a 2 channel 50W with my 2 favorite marshalls.  The 3rd/4th stages appear nearly identical - stage 3 on a plexi with an 820R Rk vs 1K Rk on an 800, both feeding a 100K Rk CF into TMB tone stack.  I'd build Doug's plexi design for blending the first 2 stages, and the first 2 stages of the 800 2204, switching between them into stage 3. 
I'd use a standard MV into fixed-bias 50W PP w/6L6's. 
I'd think this has been done a lot. 
Am I missing anything, or any suggested tips/mods?
What's last thing a hillbilly says before an untimely death?
"Hey ya'll, watch this!"

Offline sluckey

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Re: Plexi + JCM800 2 channel
« Reply #1 on: November 25, 2017, 10:11:18 am »
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline dennyg

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Re: Plexi + JCM800 2 channel
« Reply #2 on: November 25, 2017, 10:23:28 am »
LOL - YES!!! Thanks so much - now I can get to ordering the parts. 
I see there's a board layout available but I like doing my own term strip layouts using g-ring, and will post that layout when I'm done for anyone else who might be interested in that approach.  Worked out great for my TOS. 
What's last thing a hillbilly says before an untimely death?
"Hey ya'll, watch this!"

Offline sluckey

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Re: Plexi + JCM800 2 channel
« Reply #3 on: November 25, 2017, 10:30:40 am »
I look forward to following your project.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

 


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