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Gretsch 5222 rebuilt as Supro Comet

Started by timbo_93631, May 26, 2013, 06:40:28 AM

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timbo_93631

I sold the guts for this a little while ago to treeslayer and rebuilt it with a late 50's Supro Comet circuit point to point.  My revised schematic generated from various originals and with OT/PT info:

Before:



After:









I made some changes from the gutshot above to reflect a 1946 schematic I found and also rerouted some wires for lower noise.  It is now built to updated schematic above.

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Sunday Musical Instruments LLC.
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selfdestroyer

That looks great Tim. I love the sound of it also. How many hours you got into it? Did you make it for yourself or a client?

timbo_93631

Thanks Cody!  I spent a lot of time researching the different Valco single ended circuits with the 6SL7 preamp and then developed my own version by trying out different biasing and cathode bypass arrangements on the 6SL7 and redrawing those parts of the schematic as well as the transformer info.  My goal was to have a balanced tone while getting breakup to occur at about 2/3 volume.  There was also a bit of time that went into finding the right transformers, and having it be luck/providence that they bolted to all the stock locations exactly and then laying out the chassis for the extra Octal sockets. In terms of total hours, maybe 20.
To build another now that all the design work is there, maybe 4 to 6.  I didn't build it for a specific buyer, I might sell it to someone here or on OSG but I am starting to really fall in love with it.  I'm taking it to church today and I'll see how it does mic'd in a live setting.  I spent $110 on the amp and about $200 on parts including the Weber speaker and NOS tubes.
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midwayfair


gingataff

Looks stunning, really first class.
I'm sure there are few production amps with that build quality.

Sounds sweet too, who'd have thunk that much overdrive from back in the day  ;D

stecykmi


pryde


gtr2

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nzCdog

Timbo that's a very inspiring build...  :o Thanks for sharing your schematic. 
What did you use to stain the tolex?  Looks and sounds fantastic, great job!  8)
(PS what's OSG?)

alanp

Very cool. I like seeing true point to point, but I'd hate to try and do it myself :) (Mad Professor amps are the pinnacle of this.)
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timbo_93631

Quote from: nzCdog on May 26, 2013, 10:33:20 PM
Timbo that's a very inspiring build...  :o Thanks for sharing your schematic. 
What did you use to stain the tolex?  Looks and sounds fantastic, great job!  8)
(PS what's OSG?)
Thanks for the nice words guys!  Corey, I used amber shellac on the outside.  The covering on these is not cloth but a vinyl and fabric patterned covering made to look like the Valco/Gretsch fabric from the 40's.  Shellac is pretty flexible and sticks to most anything so it seemed like the best choice for this amp, Also it is easy to get a convincing worn look with some scotchbrite on the edges and in the wear areas and to take the sheen down.  After a few days to cure and the distressing I rubbed a few coats of brown shoe polish on and buffed it back off and it looks perfect.  The wax should protect the shellac pretty well.

OSG is offsetguitars.com - a great community for offset lovers and even the odd tele nut like me.

I gotta say, this little amp packed a punch today.  We ran it through the house at church and I just dimed it and used my guitar volume to clean things up.  It was impressively loud probably due to the Weber speaker.  The Webers I have had have all been very loud.  I only had a wah, fuzzface, rubadub reverb, and my old aquaboy on the board and felt like I got a lot of great tones without too much tap dancing.

On a side note the bass player at church gave me an Executone P-14 tube power amp from the 50's today with twin 2x6L6 output sections with a 5U4 on each and a 6SN7 PI.  Time to make a BIG amp now...
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pickdropper

Damn Tim, that's some good work there.
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stevewire

timbo_93631,
Awesome work!  Looks great.