(Build this at your own risk. There's lots of money to be wasted with bad woodworking skills, and lots of fingers to loose with misuse of the equipment.)

I was hoping to buy a Mesa Boogie Thiele guitar cabinet, but the price blew me away! So after weeks of searching, I found plans for a very similar cab.

The Mesa Thiele and the EV (ElectroVoice) TL806 are almost exactly the same. Many people on forums that i browsed through believe Mesa copied EV's plans for the Thiele. (They are open sourced, so it doesn't matter anyway)

The only major difference is that Mesa switched a few dimensions on their cab so it would have a flush fit under the Mark III amp head. But they maintained the internal volume of 1.3 ft, which is the most critical part.

I will be building mine with an extension on each side so it fits under my Peavey 5150, but i will not be changing any dimensions! Just adding two extra "enclosures". They were my idea, but feel free to use them, or discard them. *If you use them, be sure you make them the width of your amp head!!!* (the 5150 is relatively small compared to marshalls)

Enough words! get started! (after you read the whole thing of course.....)

Step 1: Materials/Hardware

Tools:
1. Good metal yard stick/large T-square (for precise right angles (make sure the T is still a right angle.... mine wasn't anymore, so i bought a new, bigger one!))
2. Very precise saw (table saw would be best)
3. Router (better!) or Jig saw+drill (what im using because im poor...)
4. Soldiering iron (very basic, easy soldiering... I suck at it...)
5. Drill+various sized bits including 1 inch for the TRS jack... (i will need to find one somewhere...)
6. various screws, (wood, 1.25" and 3.25") nuts and washers.
7. Wood glue.

Lumber:

1. 3/4 inch, 4'x8' sheet of Birch plywood (SUPER HEAVY! bring a friend. (if birch isn't available, MDF works too, but you will regret the choice! You need the dense wood to resonate, and make it all sound good!)) ~$51.55 at my Home Depot... Im sure there's cheaper...

2. 14+ feet of 0.75"x2.5" Fir (for bracing) (But 17+ for WIDENED cabinets!) ~$1.01 for 5 feet in HD's scrap bin.

3. 13 inches of 3/4"x3.5" Fir (part of the port...) ~$1.01 for 5 feet in HD's scrap bin.

$56.60 total on wood. (for me... (different stores probly have cheaper lumber prices.)

-Hardware:
(I bought all of mine from www.parts-express.com (except the speaker, they don't carry it... ): )

1. A 1/4" TRS jack. (I used a "Neutrik NJ3FP6C 1/4" Locking Chassis Jack Nickel") ~ $6.54

2. Corners! (I bought "Dayton MC130-16 Metal 2-Leg Cabinet Corner") (16 in a pack) ~ $6.96

3. A handle! (me: "Penn-Elcom H1014K Extra Wide Strap Handle Black End Caps") ~ $3.38

4. Wire ("18 AWG Red/Black Zip Cord 1 ft." you have to get at least 10 ft.) ~ $3.10 for 10ft

5. Feet ("Penn-Elcom F1687 Rubber Cabinet Foot 1-1/2" Dia. x 3/8" H" ORDER 4!) ~ $3.76 for 4

6. Speaker mounting kit ("Cast Frame #10-32 Speaker Mounting Kit") ~ $3.39

7. Gasketing Tape (optional, but useful for airtight seals "Speaker Gasketing Tape 1/8" x 3/8" x 50 ft. Roll") ~ $6.19 a roll

Total: $42.57 after shipping on hardware (excluding speaker)

-Speaker:
You have two choices that will work nicely. Any other speaker may risk putting the cabinet out of tune, and making dips or spikes in the cab's frequency response.

You only need one.. This cab is a 1x12, but it sounds huge! because of the ported front.
Them EV speaker is rated 200 watts, and the Eminence is rated 400 watts! so don't worry about blowing them!

1. ElectroVoice's EVM12L 12 inch loudspeaker. the cab was originally designed for this speaker, it is said to sound the best, but it is also very pricey! (lowest price i found: http://underbid.com/action/display/item/11957-1064270764/sku/ELEEVM12C8.html) ~212.12 (after shipping. www.grabcart.com (not on partsexpress... FIX THAT!!! I build these for local people!!!))

2. The other option is the Eminence Delta Pro-12A
(http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-510)

-Tolex/Grill:
TBC
for now:
http://www.youtube.com/watch?v=Gm_PYUFCPSk

-Plans!
I almost forgot!
http://archives.telex.com/archives/EV/Builders%20Plans/TL806%20Builders%20Plans.pdf

there are also some other good EV plans here:
http://archives.telex.com/archives/EV/Builders%20Plans/

Step 2: Mark the Wood for Cutting.

If you're following EV's plan, you might be able to get away with a 4x4 sheet. But don't take my word for it!

REMEMBER TO TAKE THE SAW BLADE'S WIDTH INTO CONSIDERATION!!! (Mine was 1/8")
If you're going to cut it with a table saw, you should distribute your plans mostly around corners and sides. It will be easier to get right angles, and much easier for the person cutting the wood to get a "perfect cut." (I didn"t do this..... But hey, I learned, and I'm helping you before you make the same mistake.)

-You need!-

---Plywood Cuts.
---EV Cab---
~listing on the second page of the PDF!

---My Cab---
--(in inches):
~2 Top/Bottom= 13.5 x (head width. My 5150 is 26.5)
~2 Inner sides= 13 x 11.25
~2 outer sides= 13 x 13.5
~1 Back= 13 x (whatever your head width is -1.5 Mine is 25")
~1 Baffle= 13 x 13
~2 Grill bracing L/R= 13 x (how wide the empty space is... you'll see.... make 'em later... COSMETIC)
~2 Grill Bracing T/B= 17.75 x 0.25 (you'll see....COSMETIC)

---Fir Cuts
---EV/Mine---

*Use the picture in the lower right hand corner on the second page of the PDF, or the uploaded picture.... as reference.
-In the picture, the left side is Front, and the right is Back.

~-2.5 x .75 inch Fir pieces (inches):
~2 Back L/R= 15.5
~2 Bottom, Front/Back= 11.5
~2 Top, Front/Back= 13
~2 Front L/R= 12.25
~2 Top L/R= 5.5
~4 Bottom Channels= 8
~1 Port top (directly above channels)= 13 x 3.5 x 0.75
(Widened cabs only):
~4 Outer compartment braces Top/Bottom/Left/Right= 11.25

Step 3: Cut the Wood

I used a table saw for this.... Actually my uncle did it, because he wanted me to save my hands for my guitar... He said "I only need one to paint." (he paints houses...)

If you have a table saw, you should know how to use it.... If you don't know, get someone to help you. What's the point of guitar if you are missing half your fingers?

Or just use a circular saw. WITH PRECISION!!!
If you use a circular saw, be careful, use clamps, and a straight edge!

You can use a circular saw for the fir bracing. (i cut these =)

(sorry for the lack of photos, I didn't take any pictures there....)

Step 4: Start Putting It Together (part 1)

Now. Before you start assembling the box, and putting screws into it, you should remember that you may want to use a router later, and give the cab a nice rounded "pro" look with tolex and all that. (see step _____)

So you can't put the screws on from the outside! They WILL! either damage the screw, router, bit, cab, or your face when the router runs over their heads!!!!

For now, just use glue, and clamps and stuff.

HERE WE GO!

I started with the base of the cab, marked where the permanent pieces needed to be (back cover, and baffle are removable) and took those four sides, (two for EV's original plans) and glued their bracing on them in the right spot. (two for each side.)

After you apply the glue, make sure the bracing is placed on at a 90 degree angle, or it won't fit properly! :o (see pic)

You will add screws later.... after the glue dries at a 90 degree angle.

Step 5: Start Putting It Together (part 2)

Now that you have your perfectly glued pieces, you need no apply the screws! =) (you don't have to.... but it would sure make it stronger!)

First, (Pilot holes) I took a drill bit slightly skinnier than the screws i was using. I drilled it into the bracing 3 times on each piece. (make sure you go down far enough, but not too far!

Next, (countersinking) I took another drill bit about as wide as the screw head, and drilled down just a few millimeters so the screws would easily drop into place without damaging the wood.

Screw it!
Go slowly and nicely. You don't want to split the cheap bracing (i almost did when i got excited! I was overwhelmed with power!)

Sand the areas you screwed down so they have a nice smoothness to them. Then slather some wood filler over them.
After a few hours when its all dry, sand the wood filled areas down too. Then they'll be super smooth, and you won't even be able to tell they're held together with screws! woo hoo!

After the bottom has all the pieces glued and screwed, screw on the top the same way. (It should be easy) Now it should resemble a box!!!

Step 6: Bracing!

Not much to say here. use the pictures provided.
It doesn't need to be done the same exact way.
The 3rd, through 6th pictures were found on a german website... I could find the guy's name if i tried, much less type it. I also lost the website.... So thanks, and I'm sorry.

Good luck with this part. I won't hold your hand. You have the plans (2nd step) the skills (if you got this far) and the materials i hope.

I glued them all in, and used clamps for some of the stubborn pieces. A large hammer helps to get some of the tight fitting pieces in. After glueing the pieces, drill them like you did when making the box, (I did about 3 screws per hunk of bracing) Then cover them with wood filler.

When the whole thing is together nicely, fill pretty much every corner and crack with some sort of caulk. (I used some sort of clear silicone caulk) This will stop rattling, and air leaks.

Step 7: The Speaker

Get the speaker first..... Don't do anything without it.

1. Take the baffle, and mark a circle on it. The center of the circle will be directly in the center of the center of the baffle, and the circle will have a 11 1/16" diameter.

Use a compass to trace the circle. If you don't, it will be bad....

2. Cut the circle out.
Since I'm poor, and don't know anybody with a router, I used a drill for a small hole, then stuck the jigsaw in there and ran it around the line. Unfortunately I made this hole a little big..... I need a router!!!!!! (If you wanna buy me one, go for it =))

3. Trace the mounting holes on the wood. (I did it wrong, and need to redo two of them..... Be careful)
Put the speaker in the hole, and use a pencil in the screw holes! duh!

4. Drill out the holes.
I made a few mistakes. Make sure you drill them perfectly straight down.
If you're using the parts express kit i did, drill a slightly larger hole in the back of the baffle. (like a counter sink) this is so the washer thingys will go into the wood.

If you're still having trouble with the washers (I forget what they're called) you can get them started by putting a large phillips head screw driver sort of in the groove of the hole, and hitting the back of the screw driver's handle with a hammer. Then bang the crap out of it.

5. Mount the speaker (the mounting kit uses a hex rench (allen rench?))
You should spray-paint the baffle black before doing this, if you plan to put grill cloth over the front. (I do, but I'm going to wait.)

Step 8: Install the Baffle/Back

Simply enough, screw the baffle into its spot...

I put some of the gasketing tape onto the perimeter of the hole first. It will make it more air tight.

Wire the speaker to the Input jack. [Speaker. Red wire to Positive lead. Black wire to Negative lead.] [Hack. Red wire to Tip. Black wire to Sleeve]

Then screw the back into it's spot. I put gasketing tape here too.

Step 9: Done! (and Playable)

Now you can test your cab out. but remember to match the impedance with the amp you're using! ex: 8ohms with 8ohms and 16 with 16. And dont use a spare instrument cable to connect the cab to the head!!! Its not good enough, and not meant to move that much electricity (i dont know much about it... but it doesnt work... dont try...) Get a speaker cable.... duh....

You may want to try different acoustic materials on different surfaces in your cab. (or just stuff the whole thing... but that will restrict airflow, and contradict the point of this cab.) I like a thin piece of cloth or foam on the back cover of the cab. But it's the player's choice.

Step 10: Hardware

Handle:
Drill the holes in the middle of the top, about 9" inches from one another, and screw it in with screws, nuts, and WASHERS!!!

Feet:
They have washers in them already, so simply screw them into the bottom. there isn't any real technique for doing his.

Jack:
Drill a 1' inch diameter hole in the back panel close to the top (not in the middle.) and then put the Jack into it, and screw it in with some small wood screws. (the size you should have used for the woodworking on the cab will be far too long and too wide.)

Metal Corners:
Screw them in with the same screws you used for the Jack.
This should be done after the corners are routed, sanded, and tolexed/covered. (see step 11)

Step 11: Add Tolex and Grill Cloth

I won't show you how to tolex an amp...... I'm bad at it, and hate doing it, and I'm not a good teacher.....

I found this to be a good instructable on it.
https://www.instructables.com/id/Covering-a-guitar-speaker-cabinet-with-TOLEX/

If you're still in a rut, this video is pretty good too.
http://www.youtube.com/watch?v=0Dwe4O3fk6k&feature=related

You can also paint on truck bed liner (Gator Guard II).... This makes them very very durable.... (I will do this with this cab.)

For the grill cloth....
You can't just wrap it around the baffle, because the speaker is mounted on the outside of the cab! (like bass speakers.)

You need to glue a wooden frame together and wrap the cloth around that. It can then be screwed onto the front. Make sure the wood will stick far enough off of the face of the cab for speaker clearance.
(I believe i listed these pieces of wood in the "sizes to cut" area of this instructable. I said they were cosmetic only.)

You can also wrap the cloth around some sort of porous, rigid, metal sheet.... A grill..... right.... I just don't know where to buy those...