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I've been getting really tired of lugging my ~90 lb (41 kg) 1973 Vibrosonic Reverb around thrice weekly, so I've decided to make a project of converting it into a head and cab. For those who don't know, the Vibrosonic is a combo amp with a single 15" speaker that was produced from 1972 to 1981, and it's been my primary amp for about seven years now. According to the schematic, it's functionally identical to the Twin Reverb (2x12), Quad Reverb (4x12), Super Six Reverb (6x10), and Dual Showman Reverb (head) amps of that vintage, with the only difference being speaker configuration.

1972 Fender catalog, page 42 -- Vibrosonic Reverb: Mine: I love everything about this amp and never minded the weight and awkwardness of carry until recently. I took a break from using it for a few weeks while I was awaiting parts to replace the original filter caps and recently-damaged-again reverb tank; it then took a few more weeks for me to set aside an evening to install them. During this time I used my Blues Junior, which was surprisingly a very capable replacement (minus loud clean sounds), and carting it around was an absolute dream. After going back to the Vibrosonic, I realized I needed to rectify the portability situation. Making it into a head and cabinet will require more vehicle space, but the ease of carrying two smaller and less awkwardly-weighted pieces will hopefully more than make up for it. I can also just leave the cabinet at the studio/rehearsal space during the week instead of taking it home an extra two times.

The plan here is to make the head portion large enough to accomodate the reverb tank, so it will be dimensioned as the Dual Showman Reverb head was. I suspect a tank could be crammed into a thinner Bassman-sized head, but I don't think it's a great idea to have it sitting right up next to the tubes and transformers. I'll play around with it a bit and see if the proximity makes any difference before commiting to a size. The new speaker cabinet will be the same size as the current housing for the Vibrosonic, minus the thickness at the top for the amp chassis.

1972 Fender catalog, page 39 -- Dual Showman Reverb: Those most exciting part for me is that instead of using Tolex to cover the head and cabinet, I'd really like to paint them a wonderful sixties Fender color like Surf Green. I've always really liked that color, so I'm going to try find a way to have it color-matched at an automotive paint store in an acrylic lacquer. I'm hoping this route will be cheaper than ReRanch, as I don't really care to use nitro. Acrylic dries faster and is easier to work with in my experience. If it goes well, I'd like to refinish one of my guitars in the same color -- even if it makes me look like some Custom Shop dickface.

When it's done, I figure I'll have not only a unique and nice-looking amp, but it'll also be much easier to cart around. I've drafted up some rough plans on paper to determine how much wood I'll need and what I'll need to buy. The plan right now is to use pine wood and finger joints rather than butt joints to construct it, as I've come across a great way to do it cheaply without an expensive jig by making creative use of a dado blade.

Anyway, just figured I'd puke this all out a bit early and see if anyone had any feedback or pointers. I'm hoping to get started this weekend by purchasing the raw material, and I'll hopefully have some time this week to whip up some mockups.

I would use plywood. A nice 3/4" 5 or 7 ply, baltic birch would work nicely. Southern yellow pine ply would do as well, and you could save a little $ and get AC grade as opposed to AA. The "A" side is sanded and perdy while the "C" side can be on the inside. It would likely cost more, but plywood is much stronger and durable than just plain pine.

Very cool project. I played through one of those back at a shared equipment gig. It even made my DS-2 sound good.

robrtnickerson wrote:I would use plywood. A nice 3/4" 5 or 7 ply, baltic birch would work nicely. Southern yellow pine ply would do as well, and you could save a little $ and get AC grade as opposed to AA. The "A" side is sanded and perdy while the "C" side can be on the inside. It would likely cost more, but plywood is much stronger and durable than just plain pine.

Thank you. This is fantastic information, and I've noted it for my trip to the lumber yard.

Here are some Custom Shop Pro Juniors that were kind of what inspired the paint-rather-than-Tolex idea. I'd love to have the same look, but without the stupid relic treatment; they'll definitely develop that look naturally.



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