Introduction: Meatball Guitar Amp Prototype

Greetings Instructables Community!

I have developed a very special guitar amplifier and I would love to share with you how I built it.

Before we get started I would like to share with you all of the materials required to build this amp.

Material list:

  • Gutted guitar amp, older guitar amp no longer used or toured with
  • Hardware: small nuts + bolts (any small variations will do), 1" wood fasteners
  • Adjustable wrench
  • Electric drill + Phillips head attachment
  • Hot Glue gun + hot glue sticks
  • Acrylic paints
  • Plasma Cutter
  • Mig Welder
  • 1 bag of Polyfill
  • 1/4 square steel stock (two feet in total)
  • Jigsaw
  • Large magnet
  • Stretchy Fabric (any kind will do)
  • Thick textile (canvas or linen)
  • Conductive Thread
  • Adobe Illustrator
  • 1/2" plywood
  • Strong sewing thread

Throughout this tutorial I will do my best in explaining my reasons for building this amp along with notes on how I created this version.

Step 1: Starting Off...

Instead of creating a project that I would use only one time for some special reason like an event or a show, I wanted to create a tool for making sound that I could continue to play and develop for a long time. I am a musician who loves making strange sounds and textures with my bass guitar so creating a guitar amp developed naturally. I started to create drawings of different variations of the amp in my sketchbook. As I continued to draw the amp, I thought of how I could remove the "cabinet" of the amplifier made from wood and use fabric instead. Subconsciously I was thinking about food or cooking at one point and an image of a meatball came to mind. Meat could be elegant and fancy, it could be wholesome and represent something special or it go the other way, brutal and messy. The combination of a meatball and guitar amp sounded very bizarre. I jumped right in.

Step 2: Cannibalizing an Older Amp + Building a New Base

For years I have had this Orange amp in my storage unit. It sat for a long time with no use and it seemed right to reinvigorate the amp's life by giving it a new purpose. This was it's housing in classic Orange amp attire. I removed the wood shell around the settings box and removed all hardware pieces for other projects. I used 1/2" plywood as my new base for my amp. The wood was cut using a jigsaw. After the wood was cut, I mixed up some red acrylic paint and applied two coats to the wood's surface.

Step 3: Base Structure + Painting Settings Box

After the red paint was dry on the wood, I went down to the metal shop to begin building a frame for the new settings box to sit in. This required that the original settings box needed to be cut shorter on both sides with the plasma cutter in order to fit onto the new "meatball" base. There also had to be 1/4" steel L-brackets made to accommodate a new handle that could be used when picking the amp up. Additional steel L-brackets were made to support the settings box on the "meatball" base. I painted over the original graphics of the amp that had been power coated on. I used several coats of acrylic paints ranging from: orange, pink, burnt sienna, and red to achieve a meat-like paint texture.

Step 4: New Graphics

Since I was making my own amp, I decided that I was going to rework all of the settings of the amp and give each regular known setting a new name. For example, instead of calling the setting "bass" I would call it "low gas." Instead of "overdrive" I would call it "rage." This also meant that I could rework the icons for the amp by making new ones on Adobe Illustrator. For "low gas" I felt a humanoid rump expelling flatulents was appropriate. As for "Overdrive" which was originally a zigzag like design, I replace it with an image of a tight fist for "rage." This entire graphic would be printed on sticker paper and applied at the very end of the project.

Step 5: Speaker Installation + Fabric Speaker

The original Orange amp came with a 35-watt speaker with a massive magnet attached to the back. Using that shape and form, I started to build by own speaker using conductive thread. Using techniques I had picked up from my Computational craft teacher Liza Stark I began the production of my own fabric speaker. In order to create a fabric speaker you need a tight coil for your conductive thread to follow. I decided to use conductive thread because you can sew with it onto fabric. The fabric I chose for the speaker was a tough, rigid linen that held the coil in place tightly. The starting point of the speaker (where the coil begins) is where you can run power, at the very end of the coil you can attach this to ground (make sure to keep the power end separate from the ground by laying tape over the coil to run the thread in another direction). The settings box (all Orange chip boards still intact) had a power source that connects to power and ground of the original speaker. I used that same box to connect with my fabric speaker. I also purchased a large magnet that can be used when power is running through the coiled thread. The amp is directly powered from an AC power cord. When the amplified signal runs through the coiled conductive thread, the large magnet moves the air creating sound. The first time I did this I unfortunately shocked myself a little when connected the the wall's power source. Please be very careful when any electrical device is attached to the wall and you are handling any electrical wires of any kind. I am currently working at attaching a heat/ sound control circuit to see if that helps the sound amplify out of the coil more successfully.

Step 6: Fabric Work + Completed Prototype

I used red velvet fabric packed with Polyfill for the exterior of the amp to mimic the look of a meatball. The stretchy qualities of the velvet fabric allowed me to pack a large amount of Polyfill into the sewn sections to create voluptuous forms. Once the fabric sections were sewn and attached to one another I installed the speaker into the amp's speaker cavity. Once the speaker was connected the Meatball guitar amp prototype was complete. While the amp was turned on the custom made fabric speaker was unsuccessful in producing any sound. I swapped my magnet and threw in the original Orange Amp speaker for a video demo. This is as far as I was able to take this version, and I look forward to continue to develop this project long term. Creating musical instruments and custom amplifiers is another facet to my art practice.

Please leave any constructive comments you think of, and check out my website at