Step-By-Step 4x12 DIY Build

[SALVAGED]

Here ya go, guys! As promised... here's my DIY 4x12 build thread. I built two of these cabs & they look/sound awesome. I like them so much, I sold my Marshall 4x12 cabs... :lol:

There are a few different cabs, that I based the design off of... nothing ground-breaking, so I can't really take credit for the design... but I built these because I wanted a combination of certain features that weren't available on branded cabs. I'll explain more as I go...

I only ask that nobody runs off with the drawings/pics & starts mass-producing these cabs without including me... :lol:

Ok, I'll keep adding/organizing info in this post (as I can dig up the info). There are several things that I didn't get documented with pics... so, feel free to ask questions & I'll do my best to explain what I did.

To get started with materials, you need a sheet of voidless Baltic birch (usually sold in 5ft x 5ft sheets), some 3/4" square hardwood sticks (I used oak that I had on-hand & ripped down to size), a bottle of quality wood glue (I used PL Premium), & a small box of 1" general-purpose screws.

If you ask the clerk nicely, you can have the sheet of Baltic birch ripped into four 30" squares (this is how I was able to fit it in my car... and the pieces are much easier to handle, when cutting out parts).

Safety first!

Make 2 of these for the top & bottom...

Here's the drawing for the top & bottom:

Here's the drawing for the sides (measure YOUR handles, BEFORE cutting the handle holes):

Join the corners with glue & screws...

All sides clamped... check for squareness, or else the baffle won't fit... Pipe clamps work great... and they're CHEAP to make!

Mark-up the baffle...

Here's the baffle drawing (I included some reference dimensions in (), so you can verify your mark-up before cutting):

Carefully cut the speaker holes... if they're cut too big, you'll probably have to make another one...

Glue the top of the corner braces, for the baffle to sit on...

Set the baffle in place...

I weighed the baffle down, so the expanding glue wouldn't lift the baffle out of squareness...

Doubled-up the front edge... you'll need to look at my assembly drawings (coming soon), to see more detail...

All bracing & center post installed...

Rounded edges... kinda hard to see in this pic, but I pinned the corners with dowels & glue, for extra strength. I originally wanted to dovetail the corners, but with a 14" wide piece, I would need to buy the large dovetail jig for $400... instead of $120 for the "up-to-12-inches" jig.

Installed the back... The back is completely sealed (glued, screwed, & filled) & is not removable (speakers are front mounted).

Made a removable panel...

Another shot, showing the internal bracing...

Looking back, I would recommend painting the inside of the parts BEFORE assembly... I got a bit of a buzz trying to paint the inside of the cab... whew!! Just mask off the glue areas, and you should be good to go... then assemble the cab.

Ok, so I put the camera down & got to work... unfortunately, a lot of detail pics didn't get taken... But I'll try to fill in the blanks with detailed drawings & sketches...

Kind of a cool shot...

The SALVAGED stack... ta-daaa!!!

I originally tried loading the cabs with cats... but they didn't sound very good... kinda scratchy sounding, with no audible guitar signal... but there MUST'VE been SOME signal at a high frequency, because my dog was howling. Anyways... I ended up with WGS speakers... and wow, what a difference!! :lol:

More details coming as I can dig them up!!

Casting Credits:
ShopDawg: Dave
SpeakerKitty: Yuki

 

[Hamner1]

I'm interested. 8)

 

[Mattfig]

That would be awesome....And super cool of you to offer as well...

 

[JKMV12]

I've been wanting to make my own cabinets for a while. I would be very interested in this. I tried to look for links online about designing and building cabinets but my preliminary search turned up few results. I would appreciate any info and advice you can provide on the subject.

 

[drewiv]

I'd be interested. My power tools collect dust during the winter. Give me a good winter garage project, man!

 

[SALVAGED]

Ok, guys!! I started posting details in the first post of this thread... I'll keep the info coming, as I have time to round it up (it's scattered on multiple hard-drives & flashcards... :lol:

 

[BigBrewtus]

Looks like a fun time. Keep the pics coming I am very fascinated.
Please give some details about why you chose that design too. I love
the idea of the partial open back.

 

[SALVAGED]

Please give some details about why you chose that design too. I love the idea of the partial open back.

Well... one thing that always irked me about closed back cabs... is that, they tend to rip your face off, when you stand in front of them... and they get boomy & muddy when ya step off to the side too far...

About 10 years ago, I had a Mesa 1x12 cab with a 3/4 closed back. I remember how that cab sounded consistant all over the room AND still had great bass response. That was what prompted me to build the new cabs this way... and YES, they do work well. They can do the heavy palm-muted thumping riffs... as well as fill the room nicely. I certainly wouldn't be afraid of a partially open-back cab. 8)

When I was researching building these cabs, I concluded that there are 2 main philosophies to building guitar amp cabinets.

1. Formula driven. This philosophy required a lot of math & speaker specs, to build the "ideal" cab with "correct" inside volume (to get the speaker to perform in a perfect environment) & angles to reduce standing waves. Some designs also use sound dampening material on the inside of the back panel.

2. Inefficiency driven. There is a train of thought that goes back to the First 4x12 cabinet... the Marshall 4x12 (actually started as an 8x12). Jim Marshall built the 8x12 cabs for "The Who", by packing eight 12" speakers into a single box, with the least amount of plywood as possible. The roadies complained they were too heavy & brought them back to Jim Marshall, who cut them in half... and waalaa... the 4x12 was born. That's all the math/science he used. Probably completely inefficient, but it helped create the standard for rock guitar tone. The theory is, all those "inefficiencies" are part of the tone we're so used to hearing, so why "perfect" it?

I sorta combined both theories on my cabs... I used the main outside dimensions off a cab that I love... and added a few thought-out sizes & locations for the removable panel & baffle location.

 

[SALVAGED]

Added a few drawings, so you guys can get started!! 8)

 

[drewiv]

Thanks, man. I need a few things before I get started. Good to know, I hate getting into something and have to go out and buy it. I'm wondering how the wife will feel about this project. She might think five 4x12s is too many. :lol:

 

[SALVAGED]

Thanks, man. I need a few things before I get started. Good to know, I hate getting into something and have to go out and buy it. I'm wondering how the wife will feel about this project. She might think five 4x12s is too many. :lol:

No problem!! Tell the wife you're 3 short of true wall of sound. :lol:

Heck, I wanna build 6 more, myself! No speakers though... Maybe I'll design a "stack" that folds & doubles as drum cases (as well as a cool stage prop)!! :lol:

 

[VitaminG]

that's cool, man. Thanks for sharing.

 

[BigBrewtus]

Love the shop dog too. Looks to be very photogenic. :wink:

 

[SALVAGED]

that's cool, man. Thanks for sharing.

No problem at all, man!

Love the shop dog too. Looks to be very photogenic. :wink:

Thanks, man! Yeah , he is! He's a blast to be around too... he's super content just observing!

Man... He had it made... see the green couch in the background? That's his... well, WAS... he actually ate it... :lol: He used to have a cushioned chair too... same thing... :lol:

 

[Hamner1]

So far so good. Any new updates.
Also Are you using 3/4" Birch for the baffle?

 

[SALVAGED]

I'll have more updates soon... I got a little tied up (in the middle of a refinance on my home).

Yep, I'm using 3/4" Baltic Birch for everything on the cabs... they're HEAVY... WAY more than my old Marshall cabs... probably comparable to the Mesa Recto 4x12 cab I used to own (it was really heavy too).

So far so good. Any new updates.
Also Are you using 3/4" Birch for the baffle?

 

[Hamner1]

By all means get you house in order. :lol:

I didn't think you would have spent the extr a time & $$ on 1/2 Birch for the baffle but thought I should make sure. Any chance you also have diagrams & "how too" for tolexing the cab. The corners are always a B**** for me. Likely because I am doing it wrong. :lol:

 

[SteelDragon]

Very nice work. You, Sir, are a skilled craftsman. May I ask how much money you have in materials? Probably under a $100, I would guess.

 

[SALVAGED]

So far so good. Any new updates.
Also Are you using 3/4" Birch for the baffle?

By all means get you house in order. :lol:

I didn't think you would have spent the extr a time & $$ on 1/2 Birch for the baffle but thought I should make sure. Any chance you also have diagrams & "how too" for tolexing the cab. The corners are always a B**** for me. Likely because I am doing it wrong. :lol:

Updates coming soon! I just finished up a major renovation on my home, and should start having a little more free time.

As for the baffle... Yes, 3/4" (18 mm) Baltic Birch. A single 5' x 5' sheet of Baltic Birch will build ONE 4x12 cab, with minimal scrap.

Ah yes... tolex... I actually didn't use tolex. I used a speaker cab coating, called Duratex. You can buy single gallons online. One gallon will coat FOUR 4x12 cabs easily. I used the "leather-look" method to apply it. Basically, you coat an area with a brush, and lay wax paper on it. Smooth out the wax paper, so it makes good contact with the Duratex, and then peel the wax paper off. I did 3 coats this way, and it turned out better than expected. I always get asked tolexing questions as a result.. :lol:

Very nice work. You, Sir, are a skilled craftsman. May I ask how much money you have in materials? Probably under a $100, I would guess.

Thank you, sir!! I appreciate that.

Here's a break-down of what I spent on 2 cabs. You can adjust your needs accordingly...

(2) 5' x 5' sheet of 18mm (3/4') Baltic Birch.... $65 - $80 each (somewhat seasonal)
(8 ) Caster Cups... $3 each
(2) Sets of Ernie Ball Casters... $20 (per set)
(4) Recessed Steel Handles... $12 each
(2) Pre-assembled Jack Plates (with 4,8, 16 ohms).... $25 each
(1) Roll of Speaker Wire... $10
(1 yd) Grille Cloth (wide enough for 2 Grilles)... $35
(25 ft) Grille Piping... $10 - $15 total (I think??)
(1) Box of Staples (for Grille Cloth)... $4
(2) 30" x 30" Small Sheets of 1/2" Baltic Birch (for the removable grilles... more on this later)... $10 each
(4-6) Cans of Flat Black Spray Paint (for the inside of the cabs)... $3 each
(1) Gallon of Black Duratex Coating (other colors available)... $70 shipped (shipping was high, due to regulations for shipping chemical liquids)

And several different types of screws... panheads for the handles, casters, jack plates... flat heads for the caster cups... and flat head deck screws for construction (different lengths, depending on the part). I can do some digging & report the sizes, if anyone is interested...?

 

[Hamner1]

(2) 5' x 5' sheet of 18mm (3/4') Baltic Birch.... $65 - $80 each (somewhat seasonal)
(8 ) Caster Cups... $3 each
(2) Sets of Ernie Ball Casters... $20 (per set)
(4) Recessed Steel Handles... $12 each
(2) Pre-assembled Jack Plates (with 4,8, 16 ohms).... $25 each
(1) Roll of Speaker Wire... $10
(1 yd) Grille Cloth (wide enough for 2 Grilles)... $35
(25 ft) Grille Piping... $10 - $15 total (I think??)
(1) Box of Staples (for Grille Cloth)... $4
(2) 30" x 30" Small Sheets of 1/2" Baltic Birch (for the removable grilles... more on this later)... $10 each
(4-6) Cans of Flat Black Spray Paint (for the inside of the cabs)... $3 each
(1) Gallon of Black Duratex Coating (other colors available)... $70 shipped (shipping was high, due to regulations for shipping chemical liquids)

And several different types of screws... panheads for the handles, casters, jack plates... flat heads for the caster cups... and flat head deck screws for construction (different lengths, depending on the part). I can do some digging & report the sizes, if anyone is interested...?

Very cool of you to take this time to break down the cost. And while I could probably figure it out based on wood thicknesses being joined, if you have the time it would be interesting.

30" x 30" Small Sheets of 1/2" Baltic Birch (for the removable grilles... more on this later)... $10 each

Are you talking about the 1/4 removeable panel on the back of the cab?