My new project amp!

[Frank_NH]

I picked up this 1967 Vox Buckingham head off eBay for a good price.  It's 35W into an 8 ohm 2x12 cab (which I don't have yet).  Needs a lot of cosmetic work, but the amp functions reasonably well, except the Normal channel has low output (probably a leaky electro).  The reverb sounds awesome - very Fendery!  The MRB is quite cool too, giving you three different WAH sounds.  And it takes pedals quite well.

I'm in the process of replacing all the electrolytic capacitors, which requires a lot of delicate work due to the forest of wires (see the lower picture ).   I plan to refurbish it to look and sound NOS.  Unfortunately, parts are hard to come by and somewhat pricey, but hey it's worth it.  Should be a lot of fun, and I have to say that my experience with building vero pedals at this site has given me a lot of confidence to tackle this project.

[Travis]

That is a super awesome project Frank!! I bet it will scream

I've had to replace that exact type of electro (the black and red ones). I don't recommend using NOS electrolytics, my suggestion for that amp would be sprague atoms which will be reliable and black so they'll look the part.

NOS film and ceramic caps are usually ok but electros not so much

[Frank_NH]

Thanks Travis.  I'm actually using new Nichicon axials with a slightly higher voltage rating, and some non-polar electros for the 1uF and 2uF axials.  Yes, I don't use NOS electros - I want New stock!  

The main cost is all the cosmetic parts.  The tolex and grill cloth are actually OK and will need just a few spot repairs.  However, it's missing the rubber feet, all eight corners, front logos, many screws.  The back cover is shot (see those brackets?) and it needs new piping.   I plan to make a new back cover from scratch.  Hopefully when I'm done it'll look like one of those old Coke machines that have been restored with new internal mechanisms, dent repair, and paint.

The final thing is to source a cab.  They tend to be very pricey from what I've seen, but maybe I can get an old bombed out one, recover it, and install some fab new speakers.  I'll post some pictures as I get things done.  

Here's the look I'm going for (without the trolley, perhaps).

[tabbycat]

hey frank, that looks superb. a nice find.

re the head, you should make the back (controls) the front. that's a seriously cool layout. like a cross between a moog and and old vox organ. my first ever valve amp was a 1960s/1970s wem bass valve head and cab that had some of that vibe.

i hope you can get it to do what you want to do. will follow your progress with interest.

btw where was it made? there used to be a vox factory here in the 1960s/1970s. could be one of ours.

[tabbycat]

btw this.

https://www.youtube.com/watch?v=54s3386KZVI

[Frank_NH]

Hey Tabbycat...the Vox Buckingham is part of a line of solid state amps made in the 60s by the Thomas Organ Company.  Their lineup went from the small 12W Pathfiner to the biggest, baddest, and most famous of them all, the 120W Super Beatle.

If you want to know more of the history of these unique US made amps, here's the place to read all about them:

http://www.voxshowroom.com/us/amp/index.html




   

[rocket88]

Wow man that's a hell of a project, and knowing you it's going to turn out amazing. I have to say that wiring is a total nightmare. I'm sure there's some logic to it, but it makes me hungry for pasta.

[motterpaul]

That was my "dream amp" when I first started playing. I only had the smaller Vox "Cambridge Reverb" which was also solid state. There was a time, around 1970, when solid state became the more popular than tubes, because it was all new and "far more stable" than tubes, also easier & cheaper to maintain.

What kinds of transistors does it have, Frank?

[Frank_NH]

Yes it's is a "spaghetti" wiring job, sort of the ultimate "point-to-point" wiring!    The big problem (according Thomas-Vox expert R.G. Keen) is that these wires like to break at their connection points due to age and the fact the way the insulation was stripped caused a nick in the metal which then fails.  I may try applying a small blob of epoxy to certain connection points to try to provide some support.   I have to admire the assembler at Thomas-Vox - must have been quite a chore to wire these units up!

Paul - these amps have two germanium power transistors (Delco DTG-110), which can be tempermental in high temperature environments but supposedly sound better than the later silicon transistors.  The Super Beatle was especially prone to thermal failure due to inadequate cooling.  One thing you can do is to mount a little computer fan inside the box and tap power off the 6V line to run it.  I don't think that's needed with the Buckingham as it's only putting out only 35W.

By the way, the American solid state models had British cousins:  the Defiant, Conquerer, and Supreme.  Also, the TV US line-up roughly mimicked the JMI Vox line as follows:

* Pathfinder --> AC4
* Pacemaker --> AC10
* Cambridge/Berkeley --> AC15
* Viscount/Buckingham --> AC30
* Scorpion/Royal Guardsman --> AC50
* Super Beatle --> AC100
 

[rocket88]

what isn't R.G. Keen an expert on when it comes to guitar/bass amps & effects? the man is a legend and has forgotten more then any of us will ever know, and a really awesome guy to boot.

the breakage points seem perfectly logical, and when i first started building and used solid wire i had the exact same problem with wire breakage. i think you've got a great idea on how to help add support for the wires.

really can't wait to see it all fixed up and hear how she sounds.