Here is a tutorial of how to build a speaker cabinet replica of the famous Marshall 1960a 4×12. I made a few mistakes, and had to do a few things multiple times. However, I think I can help someone else out there who’s looking to replicate this type of cabinet by showing you where I made mistakes and misjudgments. You should be able to build this much quicker and more accurate than I did, simply by learning from my mistakes. The post is long, so I broke it up into several pages, and added pictures throughout. I’ve also linked to some of the supplies needed for this build that you can order from amazon.
I don’t have a fancy shop or an elaborate workspace, as you’ll see in the photos, so when i started thinking about how to build a Marshall speaker cabinet, i figured I’d use only the equipment I had on hand. If I can turn something out this good using patio furniture as a workbench, I think anyone with a bit of know-how and some persistence can do the same or better.
There is one set of “plans” out on the web for this cabinet, but you can probably find others if you google how to build a Marshall speaker cabinet They are readily available, but they are little more than a CAD style drawing with dimensions. There is little instruction or help in the assembly process, so that’s the value I’m bringing here. Read my narrative on how this was assembled, and avoid the pitfalls that I fell into, and you should have a nice new cabinet in no time!
The Plans and the Supplies for how to build a replica Marshall speaker cabinet
I started with these plans from 18Watt.com and put together my shopping list (link coming soon). I’m not sure if someone at 18Watt actually drew the DIY Marshall 1960a CAD plan or if it was just hosted there. I couldn’t find any authorship to attribute them to. Even though it’s not really a plan for how to build it, it gives you most of the important dimensions to get going. Without this document, I would have been lost.
The first thing you’ll notice is the call for 5/8″ Baltic Birch. This is something that your local Lowe’s or Home Depot probably doesn’t carry. You’ll have to go to a lumber yard or a cabinet making supply outfit to find Baltic Birch. I searched around and only found a couple of places that carried it locally, and they weren’t interested in cutting it for me to fit the trunk of my SUV, so I substituted Oak from Home Depot, and made two big cuts in the store: enough to transport it home in the car.
I’ve played on this stack from Marshall, made out of Baltic Birch, as well as this one, and the tone, to me, is virtually identical. The big advantages of a void-free plywood like Baltic Birch is that each ply is solid Birch, and will result in better edges, miters, dovetails, etc. as well as superior screw holding capability. Since I knew I was covering this in Tolex, and using a quality wood glue on all my joints, I wasn’t concerned, and opted for the Oak.
Cut the Back Panel
My first cut was to cut out the large back panel of the cabinet. This is a simple cut, and I relied on the two square edges I had from the new piece of plywood to make it as accurate as possible. The dimensions from the pdf are 28-3/8 w x 27-7/8 h. (I did have to trim the height about 1/8th of an inch, down the road to accommodate the thickness of the tolex, and to not have a back panel that needed a pry bar to remove.)
Then, I measured and cut the space for the speaker jack with a jigsaw. I opted for a stereo/mono switchable jack, rather than an exact replica of the Marshall1960a, which would have been a single 1/4″ input. The hole in the back panel is centered and raised 4″ off the bottom. Next, I did a dry fit with the jack itself. It was snug and would be nice and tight once the Tolex was wrapped. I then removed the speaker input jack from the hole I just cut.