Three Amplifiers vs One Man. My DIY quest

Simon Says

Paramedics > Fire Fighters
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Dec 21, 2012
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I would like to share something that has been on my bucket list for years. I had a deep-seated passion for building pedals and amps, which I pursued some years ago. I even ran a successful website dedicated to classic amp and pedal projects. Unfortunately, I had to shut it down ten years ago due to some people using the parts of the website in a way that I did not appreciate.

Fast forward to today, I still have a burning desire to build three iconic amplifiers: Fender Blackface Twin Reverb, Marshall 1962 Model Bluesbreaker, and Vox AC30 Top Boost. All three are 2x12 Combo style and were produced in 1965, and they all contain the tremolo circuit. However, they have some distinct differences. The Marshall is on turret boards, the Fender on eyelets, and the Vox on tag boards. They also use different power sections and preamp designs. I consider all three to be granddads of future amp designs. Amplifier that made us rock.

For the most part, I intend to adhere to vintage-accurate specs and layouts, with only necessary improvements. However, I will make one exception for the AC30. Although I will base the layout on vintage-style tag boards, I will modify the parts placement to make it neater and more serviceable. The classic VOX AC30 component layout gives my OCD an anxiety, and I want to make it more presentable. Please see the image below for a small preview.

 
a very cool mix , good luck with the builds they sound delicious.
I went with the DG30 / Blue Sierra 50/ Mesa-Boogie Studio 22+ to achieve that sonic dream .
That would be my dream combo (pun not intended) too. All three solid amplifiers!

Can't wait to see how this plays out!
Thanks a lot; it won't be a swift build. This stuff costs money, but the main thing is, I'm on it instead of thinking about starting it for the past several years

This is very exciting! Three of the all-time classic amps, all handmade by you. What could be cooler?
A proper Super Lead or Super Bass would be even cooler. I even have a replica chassis and control plate from the limited edition George at Metropoulus did about 15 years ago. It's even relicked, as I kept it in the attic all this time. Maybe someday I'll use it.

As if I didn’t already hold you high esteem…..

Killer project(s)! Looking forward to following the progress!! I am sure I will learn a plenty as I already have from your shared electronics knowledge ;~))
I hope you won't be disappointed, boys. Despite having no EE background, I have enough experience with classic amps and pedals to hope for the best. I have put my fingers into 200W bass Hiwatt and didn't die.

First photos below. Before I begin populating components on the preamp board, I will carefully review my layout ten-times-fold and make necessary improvements. My goal is to place the preamp filtering as close as possible to all the 12AX7 stages and keep the signal as far away from AC source as possible. I will also plan a better ground scheme, too. I have decided to use Vishay metalized resistors from the CCF60 series; not so vintage correct, but The AC30 is naturally noisy, I hope to make things better.






 
Aion is great, wide selection indeed. Documentation second to none

I only had one minor issue putting mine together. The documentation about the power jack was not totally clear, and it turned out that the battery and power hot wires were backward. Fortunately, I didn't freak out and I knew how to test things. The toughest part of the fix was loosening the nut to rotate the jack because the input and output jacks were already in and I didn't want to take them out.
 
I only had one minor issue putting mine together. The documentation about the power jack was not totally clear, and it turned out that the battery and power hot wires were backward. Fortunately, I didn't freak out and I knew how to test things. The toughest part of the fix was loosening the nut to rotate the jack because the input and output jacks were already in and I didn't want to take them out.
Boy, in a different context, all that talk of jacks and nuts could be banned for being a bit too revealing!
 
I've changed my plan about my AC30. I'm going to build it as close to the original 1965 Top Boost design as possible, as an homage to the original design. I will use modern parts and make only minor modifications where necessary; I will bump the screen resistors value a little, so it eats tubes a bit less, but that's it. The bias R/C, the under filtering, the grounding - that will all stay true to vintage.

I have access to early 60s Vox AC30 plans drawn by Sinner from now non existent turretboard.org. I will modify them using Sinner's source files to '65 Top Boost version. Sinner is a good buddy of mine; he was and still is a great help with this project.

I will create a new schematic drawing of the AC30 in a modern way to match the component layout. I've already chosen the types and series for all the passive components and I plan to use Pacific Audio for the OT/PT transformers, and the choke.

I'll be away for a day driving to Berkshire but will work on the project as soon as I return.

Getting excited!
 
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This is like a birthday present to me: Psonic Audio service on a 1965 AC30. That is exactly what I'm working on. The series includes six videos featuring full-service footage in HD. I modified the layout in just a couple of hours with this on hand, now soaking in all the Lyle's knowledge.

 
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