Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: bobspart69 on March 31, 2023, 02:31:05 pm
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Ok, Can this been done with limited modification and no extreme crowding? Due to a lack of parts for an AB763 Black Face VibroVerb amp I'd like to install in a brown face chassis . I don't want the amp to look like a Rube Goldberg contraption. Can I maintain a reasonably tidy chassis with minimal modification ?Know there will be size differences in the PT and OT and I'm guessing the preamp board. Don't need the ON/ OFF switches for the channels. Or does anyone know where I might pick up an AB763 Vibroverb chassis and faceplate (preferably no logo on the front) Any input is welcome.
Thanks all,
Robert
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I think you could do it tidy in a 6G16 chassis, but that’s up to you.
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I was curious as to what your concern might be and snooped around. It seems the black chassis is only about 1/4" longer. Same tubes, same pots and jacks. Black PT slightly bigger. Seems like a piece of cake. I know there are blackface faceplates out there, but I do not know if they fit the brown chassis. I
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Believe the AB763 is bout 1/2" longer but and inch wider, deeper if you will, and there's the concern. If all can be fitted in properly a black face plate isn't necessary. Tough to find the faceplate and chassis. Brown is dandy.
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Yes here is what you want.. however he wasn't taking PayPal last time I checked his chassis are as close as you can come to the real deal. It has logo on the front though.
http://www.solandfa.com/products-Vibroverb-Reverb-Chassis-Kit.asp (http://www.solandfa.com/products-Vibroverb-Reverb-Chassis-Kit.asp)
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Correct about PayPal and last I checked none in stock. I could contact again. Marsh I believe has chassis but no faceplate. Want to make sure I can get both before ordering. Therefore the question of the switch to a 6g16 chassis. Mojotone has those.
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As far as physically fitting the parts - the one difference I see, besides a different PT, are the two bright switches. Those are the switches you said you could drop? The chassis depth should be no problem, plenty of breathing room.
And my totally silly decision would be that I like the looks of the brownface better, so I'd go that way. I have built a brownface Princeton and Deluxe; and rebuilt a brownface Concert. I love the way they look and sound. And I am so tempted to build either a Brownface Super or Vibroverb. :icon_biggrin: If I do that, I'll sell the Concert cause its so heavy I can barely move it.
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Should you find that you miss the bright switches, just use a volume control with a push/pull SPST switch.
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SPST volume switch. That's clever. Would have never thought.
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OK everyone. Hammond Electronics is showing both the AB763 (125p5d) and the 6g16 (125p6a) as being replaced by their 290dex transformer. Hate to do this but I'll ASSUME there may be no mods necessary. But it lists the voltage to rectifier at 325V and Fender lists it at 460V. I suspect I'll contact Hawk Electronics who sells them and see what they have to say. Maybe get the mounting stud distances then see if Mojotone can confirm those distances with their chassis.
Thanks all, have the best.
Robert
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I think you may be mixing apples and oranges; AC voltage to the rectifier and DC voltage from the rectifier.
Take a close look at the two schematics.
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Why not a deluxe reverb chassis and faceplate? Plenty of generic stuff on that one around. I even fitted a tone king imperial clone in one of those.. relays and all
I exclusively use blackface Bassman chassis for bigger amps. They are less wide, but an inch deeper… very nice size. But I make my own faceplates
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Hey Bobspart,
I fired up my memory banks and remembered maybe obtaining a Blackface Vibroverb Chassis. So I went to my future projects shelves and there it was - still in its box. Its really nice. has both aluminum faceplates still with their protective plastic covers, eyelet boards, and a full length brass grounding plate.
I searched and found the vendor: http://www.solandfa.com/about_us.asp (http://www.solandfa.com/about_us.asp) He had/has a good reputation.
Since I would rather build a brownface, and you want a blackface, maybe we can swing a deal. I'm happy to let it go to you for the price of a similar brownface chassis & plates. An even swap.
If interested send me a PM and we can work it out.