Elias' AC30 Special

We had a lovely customer from Chile. He was a serious guitar collector and already owned a number of amps. But, he always wanted a reliable vintage Vox AC30 and since buying a Brian May Red Special, he wanted one even more! Elias's problem was that he hated the modern Vox builds. He considered them poorly built with sub-standard quality materials and components. What he wanted was a 1960's AC30 in immaculate condition that would be reliable and look great.

So, he came to us..

First things-first, we needed a vintage amplifier. I knew we would need to strip it right back to almost zero and start again, but, for the moment at least, we needed one of those lovely old marine-ply finger-jointed cabinets. Step-forward Mr Morgan from Astrings. He'd just taken in a old AC30 in part-exchange for another item and wondered what to do with the amp. It wasn't behaving very well and he asked me if I would mind taking a look at it. I did one better than that. I bought it for Elias..

It was showing its age a little and it had plainly been around the block a few times, but it had all the bits I needed for Elias's project.

Thankfully, it still sported its lovely Woden transformers and choke and a nice pair of silvers. Unfortunately, one of the speakers had a sizable rip in the cone where something had gone through the grille cloth! Probably John Lennons mic stand.. who knows!!

With the amp back in the workshop, it was time to take a closer look..

The amp was in pretty good nick considering its age, but we decided to keep on track and strip-it back to the bare bones.

With everything removed, the chassis was seperated and the steel section machined to give additional cooling around the valve bases. The transformers were stripped and the coveres prepared for the next stage. The steel section was sent off to be acid cleaned and then re-passivated. The aluminium section was sent off for polishing and the transformer covers were sent off to be bronze-plated (along with a new brass facia panel and cabinet vents that were 22 carat gold plated!)

The re-finished steel chassis section.

The polished aluminium chassis section now loaded with valve-bases.

It was now time to bolt the amp together and build the circuit boards. These were all built on 2mm FR4 which provides a strong and stable base for the wiring. We built the boards to the same size and format as the originals such that everything would still line-up. New boards were built for the power section as I have never considered the Vox design to be that great!

The amp was finished and duly tested. She worked beautifully and sounded even better!..

Now it was time to move on to the cabinet itself. In order to fully assess the damage of 50 years on the road, the cabinet was stripped back to the ply.

Once it was stripped, we could see what repairs were needed. Thanfully, not too much. Some of the rear beading had crcked and splintered, so we grafted some new timber in where required and re-finished. The leading edges were battered to pieces, so they were filled and sanded. The cabinet was then fitted with M5 inserts (rather than relying on woodscrews) and recovered in basketweave Tolex. New piping was installed along with new corner protectors and rubber feet.

The lovely finger-jointed ply cabinet..

Cabinet finished we moved on to the front baffle. This too needed to be fully stripped-back as the cloth and backing have been severely breached by John Lennons mic stand (probably a boot! and it probably wasn't John Lennons!). Back to ply, it was first recovered with gauze to provide a little more strength and protection to the cones.

Vox vintage cloth was then stretched over the appertures and stapled and Tolex glued at the top. New piping was added around the outside and a new piece of shiny 'T' trim was knocked into the seperating slot before a new VOX badge was fitted.

It was now time to re-assemble the entire amp!

The re-furbished cabinet was loaded with a fresh pair of Celestion Blues as requested. Elias also wanted to be able to run the amp in BM mode, but not at full volume, so we integrated an attenuator as part of the build.

The finished amplfier just prior to being shipped to Chile..

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