Marshall Computer

In this instructable, I will guide you through the steps necessary to build a computer within an old guitar amp.

I recently got some old industrial computers from my work. I was looking for a way to use those / make a "side-computer" for music / simple applications. I had since a couple years a Marshall amp MG-30FX which stopped working (don't know why and couldn't get it to work again). So I decided to build a computer inside the amp.

The goal was to have a fully functionning PC for internet browsing with a nice and design look.

Overall I'm really happy with the result. This is a unique object which I find beautiful as well as usefull.

Cost:

If you like me have all components from old computers it can cost you about nothing. in my case I bought the speakers, the webcam, the wifi dongle, the LEDs and the screen controller. This sums up (for me) to about 50€

Time:

Once again depends a lot on the build, I screwed up a bunch of time due to lack of planing. All in all it took me about 20-30 hours including design, and screw-ups. I would guess about 15-20 hours with the instructions and design ready.

Complexity:

Basic knowledge in Computer builds, electronics necessary. Acces to some tools for 3d printing, cutting...

Step 1: Computer and Other Components

Conccerning the computer, I got my hands on 4 old industrial computer, I spent a day building those apart and gathering the components I wanted for one build.

You can use an old computer or buy a new one (in this case watch out for components compatibility).

Computer components:

• A motherboard: it must include a CPU with cooler and RAM. You will want to check, a compatibility for screen connections with the screen you will be using. Also a audio output is necessary if you want to build those speakers in.
• A power supply
• A HDD (hard drive for OS and file system), in my case I used the hdd of an old laptop.
• A CPU fan
• A fan for the case
• Connecting cables such as Sata
• A computer screen. In my case I built the screen of an old broken laptop, which i redommand since those are really slim.
• If Using an old laptop screen, you will need a controller board. Informations to find this are given in the section about the screen.

Other components:

• An amp case
• Speakers, I used those ones, since they were powered by 5V and therefore over USB. I bought those for another project but didn't use them. However I do not recommand them, the sound is terrible (very trashy sound and no bass, for the price I didn't expect better). I recommand building better speakers, looking for the tensions available from your power supply. The only problem can be the placeneeded for better speaker.

Other components optional:

• A USB Webcam. I used this one: Logitech webcam as it is the one I already had on my PC and I could check, that the size would fit in the case
  
• A USB dongle if you want internet acces (you can of course use an ethernet cable, but that is one more cable to hide). I used this one LINK, as I will be using a linux system and this dongle is compatible, you can uye any usb dongle.
• LEDs for backlights. I used those, as they were powered on 5V so over USB. I also really like the warm white, since it gives a bit of an old retro look which fits perfectly the marshall gold design/colors.
• a switch button to turn on/off the computer (connects to the motherboard)

• Some wood screws

Tools:

• A set of standard tools (amongst other potentially torx screwdriver necessary in my case for motherboards screws)
• A 3D Printer (if you want to have a nice finish, and set the components exactly how you want).
• A hot glue gun (can always come in handy)
• a soldering iron
• a Drill
• a jigsaw
• a milling machine if you want seamless backlights (I used a handheld milling machine)
• aDremmel or similar hand milling/cutting can come in handy for small operations or finition

Step 2: Planing Build

This is a very important part of the project (which i screwed on various aspects, which cost me multiple lost prints and hours).

In this part, you will have to validates the position of the components in the amp case.

First I recommend building your amp apart and getting various boards, power supply and the mains speaker component out.

This phase depends a lot on your case and your components. However importants rules to consider during the planing are followings:

• First placing the motherboard (since it is probably the biggest components)
• Placing the power supply so that the power cable comes out somewhere acceptable (best lower on the case and if possible on the back pannel which wasn't possible in my case).
• always watch for cable length (for example power supply to motherboard, since this cable cannot be changed)
• Think of the spaces used on the inside of the case as well as the space used outside. In my case for example, the fans have a metal plate on the outer side which is bigger than the fan itself.
• If you have powerfull speakers, do not place them near your hard drive

At the end of this You must define the position of the components that show on the outside of the amp, in order to validate the cuts to conducts on the amp.

I recommand drawing on the inside and outside of the case (clean afterwards), as well as putting the components on their future position (for example the motherboard and speakers...).

Step 3: Printing Various Parts

Next you will have to print the parts needed. Some of the parts I designed are more or less specific to the components I used.

I used black PLA on all parts.

Following files:

• "cd_player_border_v1" and "cd_player_border_v1" are 2 possibilities, I used the one with 3 screws after printing the one with 4 (which turned out not fitting the case)
• "holder_hdd" is a simple "belt" for holding a 2.5 inch hdd in place
• "mini_speaker_holder" is used to keep the speakers in place. This is specific to the used speaker, you can design your own or glue the speakers (if light enough)
• "screen_fixation" x4 for holding the screen in place
• "speaker_output_side1" and "speaker_output_side2" are the sound output, they are basically mirrored. You can print them bigger to fit you needs (I wouldn't recommend smaller, since the little holes might be difficult to print.
• "screen_buttons" are just prolongations to reach the buttons to control the screen.

Only additional touch was hand painting the marshall logo as well as outer border on the sound outputs.

All files are also availables on Thingiverse: LINK

Step 4: Spray-painting

Next step was to spray paint the parts that are visible on the outside of the computer. In my case:

• the power supply
• the cpu fan
• the main fan
• the 3d printed sound output
• the 3d printed screen buttons
• the 3d printed screen holder
• the 3d printed CD player border

During this step you should be using a protective mask to avoid inhale paint.

All electronical parts should be protected (i taped some newspaper between the gaps and on the side). Specially the power supply and fans should be covered on the area you do not wish to paint.

Step 5: Preparing the Amp Case

Next step is preparing the amp case. From the planing you should have a Layout of the components on the outside. This should be very carefully planed (caliper can be very helpful). Once you cut the amp there's no going back. I would recommend placing the parts in the amp case before, just to detect and avoid simple collision problems.

Once you're sure of the position, you can cut starting on the angles with a drill, and cuting lines with a jigsaw.

Once again do wear a protective mask during this, the wood and glue used generate a lot of dust that you do not want to breathe.

You might also want to predrill on the fixation points for various components (for example power supplly), depending on the size of the wood screws you are using.

One additional step that I achieved only later (but should be done at this step), is to drill through on the side of the amp for the control buttons for the screen. You should carefully measure the distances of those and define a specific position where you want them. I also recommend drilling 1-2 mm wider than the buttons really are, since they otherwise tend to get stuck at the entrance of the holes.

Step 6: Optional-Backlights

I did implement some warm white led lighting on the back side of the amp which do give a very good look on the end result.

You could just choose to glue the led strips on the back. I chose to mill a "channel" in order to keep a flat clean back pannel. I mill the channel with about 7 mm depth and 12 mm width oder a length of about 300 mm. at the end of each channel I drill a hole through the pannel in order to hide the connections.

I used the original power supply button of the amp to switch on and off the leds. I just added the button on one of the line feeding power to the LEDs through USB.

When this is done, I cut 3 LED strips of the desired length and solder them together.
I then pass the soldered striped through the holes and glue them inside the channels (with the built in adhesive strip).

With this, the LEDs backlights are ready. They are seamless from the outside, can be switched on and off with the power button and get powered through USB (will be connected at the end).

Step 7: Building the PC

In the next step all components come together.

• First mount the motherboard
• Build all components visible from the outside (power supply, fans, cd player, cd player border, sound outputs)
• Build the other internal components (RAM / CPU if not yet implemented, Hard drive with its holder)

• Build in the Speakers and set them in place (in my case with 3d printed part)

USB Plugs:

In my case, I wanted usb plugs on the outside of the case (since I do not have acces to the motherboard main panel). For this I used a double usb plug cable that could after minimal rewiring be plugged directly on te motherboard (look into datasheet if you have it, otherwise it might be written on the board itself).

Webcam:

I also wanted a build in Webcam, in my case, the two plugs for audio in and audio out on the front pannel of the amp had acceptable position and distance for me to fit the camera and it's microphone. Since the space was a bit narrow, I had to build the camera out of it's case and mill a part of the case. Oce it was done, i used sand paper to roughen up the camera's surface as well as the surface inside the amp, in order to achieve a better bond strength when gluing the camera in place. If you do not have the right holes for your camera and microphone to look through, you can simply drill them yourself.

Power Button:

I also wanted a computer power button (and not just the power switch of the power supply) to boot the computer. To this end I build out one of the Audio Jack (Foot controller) and built a switch I had spare. This way I can startup the computer with a button on the front panel.

Step 8: Implementing the Screen

The next and almost final step concerns the screen.

Connecting the screen:

In my case I used an old laptop screen panel. I looked on the back of the screen panel to find the reference needed to get the correct controller. In my case it was B156XW02. With this reference you can find a corresponding controller board on ebay/amazon.

In my case I bought this: Link, which worked perfectly.

I first tested the panel with controller and used the opportunity to change the language settings (default chinese i think).

Power supply:

The screen controller board takes 12 V input power supply. luckily on one of the power connector of the computer power supply, I could find 12 V. I cut of the connectors (power off) and connected those to a cable with the correct power connector.

Passing cables through the net:

The biggest challenge in my case for the screen was to make a "hole" in the "net" of the amp, without getting some loose string. to do this I used 2 little ply-wood frames that I cut out with a dremmel. I glued both of those from both sides of the net in front of each other with hot glue. Once dried I added hot glue on all sides and all edges. After that and to guarantee a constant pression on the cuts, I screwed a bunch of wood screws through both plates. Beware, that the head of the screw (flat part) looks towards the outside of the amp, otherside you might damage you screen.

When everything was done, I carefully cut the fibres in the "secured area", to clear a path for the screen cable.

Screen controls:

Last but not least, getting acces to the control buttons of the screen. The screen controller comes with a little separate board (connected together via cables), that allows you to adjust screen settings (like any normal desktop screen). Just secure this in place where you drilled the holes with wood screws, and from the other side screw the 3d printed screen control buttons.

Finishing:

Once this was done, I could secure the controller board in place with 2 wood screws, get the cable connecting to the screenconnected, secure the screen in place with the 3d printed holders. You can now plug the screen into the computer and the power into the board.

Step 9: Final Step and Boot

Most of it is then done.

Now you can plug everything together:

• Sata data cables from CD-player and HDD to Motherboard
• Connect power supply to HDD, CD-player, power board, Screen...
• Connect the Webcam, Wifi dongle, LEDs backlights, Speakers (audio and power with usb)
• Connect the fans on the motherboard
• Connect screen and its powersupply if not yet done
• Connect the power button to the motherboard
• Connect the externals USB plugs

Once everything is connected you can switch the power on.

If everything has been done correctly, this is from now on classical computer configuration, and booting a system from the HDD/SSD or installing it from the CD player or per usb.

I installed ubuntu 18.04 and everything works fine.

I also rendered background image with blender which you can download. the image I rendered is the exact resolution of my screen, if you want to render it differently you can used the enclosed .blend file. I added some visual effects with the filters available on my phone (because it's easy and nice, you can photoshop it if you wish).