Got a new head cab for my Mesa MKIV and now everything is zebra print

BSRIAudio

Active member
I got a good deal on a MKIV in a rack kit a month or so ago and after looking around I was able to order a new head cab for it from @Metalone72. His craftsmanship is absolutely top notch. I was originally planning to just get regular black tolex and have it look stock but then I saw this zebra tolex and couldn't resist. I had to double down on the vibe and design a new PCB for the footswitch circuit that copies the logic switching scheme of the original Mesa FU3 but in an enclosure 1/3 the size and made the faceplate zebra print to match. Its a whole vibe.

5GpwDwnl.jpg


Mesa's switching system on these is pretty cool. The footswitch is a simple 5V logic-based computer that uses an encoder, decoder, and inverter to perform all the switching functions without the need for programming a microcontroller or using six cables to cover all the switching functions on the back panel. I wired up a prototype with the first PCB out of the pack in a less-glam aesthetic:

A9c3pHXl.jpg

ChqpWZhl.jpg


Fun project and now everything is ready to rip. The head sounds killer through my EVM12-loaded 4x12 which is kind of unusual for mesas. My MKIII is overly bright through the same speakers.
 
Last edited:

ClintN667

Well-known member
I got a good deal on a MKIV in a rack kit a month or so ago and after looking around I was able to order a new head cab for it from @Metalone72. His craftsmanship is absolutely top notch. I was originally planning to just get regular black tolex and have it look stock but then I saw this zebra tolex and couldn't resist. I had to double down on the vibe and design a new footswitch that copies the logic switching scheme of the original Mesa FU3 but in an enclosure 1/3 the size and made the faceplate zebra print to match. Its a whole vibe.

5GpwDwnl.jpg


Mesa's switching system on these is pretty cool. The footswitch is a simple 5V logic-based computer that uses an encoder, decoder, and inverter to perform all the switching functions without the need for programming a microcontroller or using six cables to cover all the switching functions on the back panel. I wired up a prototype with the first PCB out of the pack in a less-glam aesthetic:

A9c3pHXl.jpg

ChqpWZhl.jpg


Fun project and now everything is ready to rip. The head sounds killer through my EVM12-loaded 4x12 which is kind of unusual for mesas. My MKIII is overly bright through the same speakers.
Where did you get the PCB? I would love a footswitch like this. I hate the huge one that I have.
 

mcstinger

Member
Looks pretty good in that zebra tolex :). Nice clean job on the footswitch. If I had such a patience. Just finished MIDI/DAW/amp controller, based on old Engl Z12 and it's a huge rats nest of cables.
 

BSRIAudio

Active member
Looks pretty good in that zebra tolex :). Nice clean job on the footswitch. If I had such a patience. Just finished MIDI/DAW/amp controller, based on old Engl Z12 and it's a huge rats nest of cables.

They use serial cables for all that stuff, right? What a nightmare. This design is a ton of offboard wiring which is a pain but I wanted the board to be flexible for different enclosure sizes if I needed to do something smaller.
 

mcstinger

Member
They use serial cables for all that stuff, right? What a nightmare. This design is a ton of offboard wiring which is a pain but I wanted the board to be flexible for different enclosure sizes if I needed to do something smaller.
That was defective MIDI controller, not SAC. I have used just the case and switches. Made new MCU board, 4 pcs I2C relay switch boards and added lot of LEDs, so there are around 50 wires or so :). In the original there was a small main board with MCU and display, then just wires from switches. And yes, I hate offboard wiring :)
 

BSRIAudio

Active member
That was defective MIDI controller, not SAC. I have used just the case and switches. Made new MCU board, 4 pcs I2C relay switch boards and added lot of LEDs, so there are around 50 wires or so :). In the original there was a small main board with MCU and display, then just wires from switches. And yes, I hate offboard wiring :)

I've become so used to running 6 wires and a single ribbon cable in my production pedal designs that 30 wires in one of these is a drag.
 
Top