Doug's reverb mod

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Jimichile
Junior tube assistant
Posts: 3
(5/25/05 10:49 am)
Reply  Doug's reverb mod
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 someone have a schematic version of the Doug's reverb mod?
I'm new to tube electronics and I don't know how to insert it the project.
thanks

Jimichile

 
PhatTele
Junior tube assistant
Posts: 63
(5/25/05 11:54 am)
Reply  Re: Doug's reverb mod
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 If you're new, your best bet is to think of that Add Reverb to the Western Electric Circuit information as a scratch build opportunity and not something you would use to mod an existing amp. With that in mind, take a look at Doug's drawings for the 5F6a Bassman, AC30, and Plexi 50. Compare the input section of the preamp for these three circuits to the drawing for the "add reverb..." You should see the similarities between all four drawings. From that, I used Photoshop to cut and paste together a drawing that I used for a custom built circuit board layout. It worked out fine.
 
tubenit
Hey get your own solder
Posts: 260
(5/25/05 8:16 pm)
Reply  What type of schematic
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 Jimichile,

What type of schematic are you using to attempt to add reverb to? I have done 6 amps that use one 12Ax7 for reverb that have been successful for me. You can look at schematic heaven and look at a Gibson GA17-RVT Scout and/or look at Blue Guitar website under homebrew amps and look at the Carolina Blues Special schematic to see other examples of using one 12AX7 for spring reverb that will work. tubenit
 
Jimichile
Junior tube assistant
Posts: 4
(5/27/05 2:43 am)
Reply  Re: What type of schematic
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 I'll use a 5F6A schematic, but since I'm REALLY newbie I have some difficulty separating the reverb circuit from Dough drawing... comparig the various drawings too....

 
gehicks
Senior tube assistant
Posts: 141
(5/27/05 6:16 am)
Reply  Re: What type of schematic
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 I *really* like Doug's AB763. Of course it's a different beast in a lot of ways but you've got your reverb there with a proven layout.

Maybe build a proven design first to get more familiar?

Don't underestimate the difficulty you can run into with layout issues. I've built quite a few amps and I'm still hesitant to get too far off the beaten path having burned myself a couple of times.

Cheers,

Jerry.


Edited by: gehicks at: 5/27/05 8:48 pm
 
tubenit
Hey get your own solder
Posts: 262
(5/28/05 6:09 am)
Reply  Re: What type of schematic
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 Jimichile, If you are using the 5F6a, then Doug's reverb circuit will work with your amp. If you are having problems reading the layout/schematic style that Doug is using ........ then print off a schematic of a 5F6a and use that for your schematic foundation and follow Doug's schematic and draw in his reverb circuit into the 5F6a schematic. If you have some amp building/schematic reading experience, I think you can do that if you will be patient with the process.

Doug's stuff works! Besides being a superb business man, he knows his amps and I find his knowledge and approach to be rather brilliant. I'd stick with his design and draw it into your schematic in a way that you understand and use that. On the builds I have done that eventually worked (using one 12AX7 for reverb), it tooks me dozens of hours to tweak the first one out. Doug has done that work for you already.

OK, ....I got curious and had to see if I could draw this out for myself. Looking at what I've drawn and Doug's layout/schematic, it appears to match up as best as I understand it.

This is a crude cut and paste and draw of Doug's reverb into an original 5F6a schematic. I think it is correct, but can't guarentee that as I have not wired one up this way? If you would like to look at what I have done for a possibility , email me at js2x@carolina.rr.com. If you try it , please post the results.  

If you have the means to post the schematic for others to review it's accuracy, please do so.

If you're not experienced working on amps and don't know how to do so safely, I'd just skip attempting to add reverb.

Edited by: tubenit at: 5/28/05 4:11 pm
 
tubenit
Hey get your own solder
Posts: 263
(5/28/05 7:53 pm)
Reply  Re: What type of schematic
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 BP-Plickner was gracious enough to help post the schematic for review. Please let me know if there are any errors in it.

mysite.verizon.net/dogtone/AmpPic/5F6a%20Doug%27s%20REV.JPG

Thanks, tubenit

Edited by: tubenit at: 5/28/05 7:56 pm
 
BpPlickner
Junior tube assistant
Posts: 33
(5/29/05 9:02 am)
Reply
  Re: What type of schematic
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 Tubenit
Thanks for the schematic, The link hits your new and improved version
  
BP
 
Jimichile
Junior tube assistant
Posts: 5
(5/30/05 3:16 am)
Reply  Re: What type of schematic
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 thanks alot boys, now I'll take a look to it!
I'll let you know!
 

Jimichile

 
 
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