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Discussion Starter #1
So, the last of the caps that I did not have kicking around finally arrived and the build has begun. I'm creating this thread so folks can follow along ...and in case I get stuck and need some help from folks who now much more about this kind of thing from me.

I attach a copy of the schem, the wiring diagram and various pictures of the parts that I am working with. I will post new pictures and comments as things progress (note: progress will likely be slow since I have things competing for my time - day job, wife, 4 children, dog and guitars that demand my attention).

Cheers.
vibverb.jpg vibroverb_ab763_layout.gif chassis.jpg cab.jpg boards.jpg hammond_trannie_PT.jpg trannies_choke.jpg

PS. Cab built by Derek Bell (February 2018).
* Chassis by TubeAmpDoctor - Germany
* Hammond PT (NextGen)
* OT, RT and Choke - Mercury Magnetics

** A big shout-out to my new favourite company 'DigiKey' (digikey.ca). I shop Canadian (NextGen) for passive components whenever I can and use Digikey when I can't. They're American BUT they ship for free by Purolator, allow for shopping in CAD and cover the duty (if applicable). They rock.
 

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Discussion Starter #5
Hoping so. Its certainly a challenging build.
 

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Discussion Starter #7
What are you doing for the faceplate?
The chassis and face plate are actually for a super reverb...which you likely know means that there is a 'hole' for the Mid pot. I will be using this extra pot spot for a type 2 (PPIV) MV.
 

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Discussion Starter #9
Finished the board leads tonight and while I do enjoy piecing the board together, I'm always happy when this part is done. Please feel free to scan this thoroughly and tell me if I made a mistake. I am all ears, as they say.

board_leads.jpg

Questions for the community:

1) Are the underboard wirings correct? I found the diagram ambiguous (D, X, Y and Z). I am not confident that I have read this properly (though I did reference the schem).

board_leads_rear.jpg

2) I am open to suggestions about heater wiring. What do folks think: chassis-hugging heater wiring or flying dutchman style? I need to decide soon since I will be installing the board shortly (barring an epic mistake as mentioned in item #1).

Most of the more innovative designs I have seen from electrical engineers are using the elevated heater wiring instead of the old Fender way of doing it. I'd love to hear thoughts on this. In the meantime, peace and great tone to all.
 
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Discussion Starter #10 (Edited)
Right. Jolly well have to carry on alone. Can't have monsters about.

So, moving along, the PT has been wired up.

pt_wired.jpg

and so have the (always exciting) input jacks.

inputs_wired.jpg

As an aside, I have decided to go with flying buttresses for the heater wiring. Its all very exciting.

Tubes have been ordered. Mullard power tubes (including two matched 6L6s) and matched JJs in the preamp section.

Found out that I had forgotten to order the 120 PF tone caps. They will arrive wih the tubes (mid-week, like as not).
 

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The chassis and face plate are actually for a super reverb...which you likely know means that there is a 'hole' for the Mid pot. I will be using this extra pot spot for a type 2 (PPIV) MV.
Honestly, I'd put in a mid pot. It will be far more useful than a MV on that amp.
 

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Discussion Starter #12
Honestly, I'd put in a mid pot. It will be far more useful than a MV on that amp.
Yeah, so I have entertained this debate - it is not a new one and appears on other forums and relevant aricles on the subject.

My thinking (and, ultimately, my decision): I can control the mids with the tone caps on the board and actually match the tone caps to the fat 50s (in my Strat). More, it is easy to back out of it, remove the MV and add a mid-pot (a la the super reverb) if I find I'm craving even more control over my mids. For now, the tone caps on the board are just a starting point - I am expecting to tweak them a bit before declaring that the amp 'complete' - and the MV mod stays.
 

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Yeah, so I have entertained this debate - it is not a new one and appears on other forums and relevant aricles on the subject.

My thinking (and, ultimately, my decision): I can control the mids with the tone caps on the board and actually match the tone caps to the fat 50s (in my Strat). More, it is easy to back out of it, remove the MV and add a mid-pot (a la the super reverb) if I find I'm craving even more control over my mids. For now, the tone caps on the board are just a starting point - I am expecting to tweak them a bit before declaring that the amp 'complete' - and the MV mod stays.
I built mine from a Super, so I already had the Mid pot, but I'd never dream of getting rid of it. It's basically my main tone knob. I set the bass and treble at the start of the night, and then tweak the Mid knob as needed.
 

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Discussion Starter #14
I built mine from a Super, so I already had the Mid pot, but I'd never dream of getting rid of it. It's basically my main tone knob. I set the bass and treble at the start of the night, and then tweak the Mid knob as needed.
I suspect this comes to personal taste and individual set-up/style. I have never had a mid pot on a vibroverb - or even a vibroverb for tha matter - so I won't miss it. I actually think I may have the passive components kicking around to do a DR build - which would definitely have a mid pot.
 

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I suspect this comes to personal taste and individual set-up/style. I have never had a mid pot on a vibroverb - or even a vibroverb for tha matter - so I won't miss it. I actually think I may have the passive components kicking around to do a DR build - which would definitely have a mid pot.
I wish I had one on my Princeton Reverb. I might just replace the bass pot with a mid pot. The bass knob is always at zero.
 

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I think if you wanted both you could easily mount one on the rear panel.
 

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Discussion Starter #17
I wish I had one on my Princeton Reverb. I might just replace the bass pot with a mid pot. The bass knob is always at zero.
I am not sure which princeton (year/circuit) you have but there are lots of mid-pot mods out there. Rearranging the real estate would be a pain but the wiring looks pretty straight forward.
 

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Discussion Starter #18
I think if you wanted both you could easily mount one on the rear panel.
Yes, the ground switch is useless so it could easily go there. There is also room on the front panel (between jewel and intensity pot). I have seen pictures of a AB763 VV that had this done to it.
 

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I am not sure which princeton (year/circuit) you have but there are lots of mid-pot mods out there. Rearranging the real estate would be a pain but the wiring looks pretty straight forward.
Mine is a Pepco built clone from 1973. Unfortunately my tone stack is all PEC's like an old Ampeg. I'd have to do the whole front end over from scratch to change it
 

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Discussion Starter #20
Mine is a Pepco built clone from 1973. Unfortunately my tone stack is all PEC's like an old Ampeg. I'd have to do the whole front end over from scratch to change it
Oh. :(

Well, I guess you could always just build your own. Its time consuming to do it right but it might be worth it for you if you reeeeeeally need that mid-pot.
 
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