New 36 W build, JCM 800 pre-amp

Double-Bubble! Place for discussing the 36W version...

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New 36 W build, JCM 800 pre-amp

Post by guitar-rocker »

I just finished another 36W build, with the B+ and the power section built off of the 18W design and values, only double bubble. This amp features a quad of 6V6's, typical 18/36W B+ rails, dropping resistor values, & cathode bias. The preamp is a JCM800 2203. For the PT I used an Edcor 200ma 310-0-310, OT the MPS 42va. It has a lot of gain. A lot of gain. Pretty much it turned out about as well as the Baby Blues JTM did. Thanks to Phil for his suggestion to not lower the 470K's. And a few photo links:


http://i938.photobucket.com/albums/ad22 ... nside2.jpg

http://i938.photobucket.com/albums/ad22 ... opview.jpg

http://i938.photobucket.com/albums/ad22 ... board1.jpg
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Bronsboi
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Post by Bronsboi »

Guitar rocker, your layouts are so tidy, it makes me want to weep when I look at my amps!
How do you like the tone compared to your other 36watt builds?
Great work.
Dave Brons
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Post by Daviedawg »

Your layout is a work of art. It is a shame to hide it in the chassis.

Dd
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Post by guitar-rocker »

Thanks Davie, I try to make them tidy. Kind of like a muscle car, goes fast, but does anyone ever look under the hood at it? The tone is all that counts though.
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Post by guitar-rocker »

Bronsboi wrote:Guitar rocker, your layouts are so tidy, it makes me want to weep when I look at my amps!
How do you like the tone compared to your other 36watt builds?
Great work.
Dave Brons
Thanks for the compliment, but I fought the layout a bit, and will probably change a few things on the next one to clean it up a bit more. I think I like the 6V6 roar a bit better than the EL84, but this one is definely is an 80's toned amp.
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Post by basicbill »

Very Nice ! Thats the way my amps aare supposed to look :oops:

Ordering parts for the Phat ass today, we'll see ! :twisted:
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Post by guitar-rocker »

I finally got a clip of this amp up:

http://www.youtube.com/watch?v=MVZEBkEq ... e=youtu.be
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Post by scottva59 »

Great 80s grind and a beautiful build!
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Post by guitar-rocker »

Thank you much. It hit what I was aiming for, so I'm pretty happy with the build. Ad of course Mr. Brian Story who played and recorded the clip does a very good job with his playing too!
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Post by lespaulplayer »

That clip sounded AWESOME.
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Livin' the 18 watt lifestyle! :kool:

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Post by Bronsboi »

Beautiful tone, sounds better than the Jcm I used to own! Congratulations
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Post by guitarmike2107 »

Looks and sounds great, nice work, well done!!
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basicbill
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Post by basicbill »

Impressive Tone !
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Post by zaphod_phil »

Love that tone!!!

Could you also post it into the Hear It! section, so people can find it easily later...
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Post by guitar-rocker »

ZP, It would be my pleasure to post the clip there.
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Post by guitar-rocker »

My thanks to all for the very nice compliments, Scott, LesPaul, Dave, Michael, Bill and Z. Phil. Thanks Michael for your excellent service on the parts, which I could not do without.
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