The "Custom Control" thread for modders and fiddlers in the controller area.

We have had a couple of mentions of custom built controllers recently and I thought it might be interesting to see if there are any other members out there who have built their own customised control units.

There are always criticisms of how much the H&K amps can do with so few controls and I must admit, I see the point. For me the best way is to set up a way of banging out full amp reconfiguring messages so the entire set of controls can be changed in one hit, but others may have a clever way of allowing access to every one of the options individually, who knows. Anyway, let's hear your thoughts on this one way or the other.

Just curious. Are you referring to a MIDI controller. Neither of my H&K amps has that, so I haven't messed with it.

The thing that got me into starting this thread is that I actually build and programmed a controller for my Marshall JVM205H.  The original was fine but only had 4 buttons to control 6 functions.  These had to be recinfigured (easy) to give them control over parameters which were not already covered.  It also had no way of reconfiguring the entire amp with a single stomp.  I opened it up to having 6 switches for control and 1 to toggle the mode.

In Stomp mode it used the six switches dedicated for each amp function so I had total control of all parameters.  I programmed in a Patch mode where I could store whole amp configurations and select them as I wanted in blocks of 4.  The patches of each block are accessed using 4 of the switches and the other 2 switches are "bank up" and "bank down" functions to scroll between the blocks.

It is Arduino based as those little beasts have a fantastic input/output capability and you can add in displays and storage on their I2C lines very easily.  I had two options with the Marshall.  I could use their MIDI input or I could use their own dedicated line for their own controller which is a Marshall bespoke protocol.  I spent a couple of evenings cracking that with a scope and it was easy.  They used a very logical format for both hardware and software, kind of a higher voltage single sided RS232, which I could blag into simply by building up a pair of bytes to represent the whole state of the amp.  These were passed along a 22V line to the amp pulling it down to 0V where it was necessary.  Their own controller was actually powered by the same line but I chose to power the Arduino separately simply because I didn't think the line would stand the current draw.

I just wondered if there were any "fiddlers" out there who had done similar things that I could pick up ideas from.

I'm actually working on an in-guitar controller of this sort. My current design is based on the Picaxe family of microcontrollers. The idea is to do a "Jimmy Page" style LP functionality, but without all of the inherent problems of the JP push-pull setup. With the exception of a few passive components, it only uses one Picaxe controller and one Maxim switcher. The Maxim switcher is a more robust I2C version of the venerable old 4066 analog switching IC.

First of all, I beg your indulgence for my poor English level (Thank you deepL!!).
Three years ago, I bought a GM36 amp, which gave me complete satisfaction...except for the access to the stomp mode settings. Too few buttons for too many parameters to control in real time on stage. In my opinion, the FSM 432 MKIII footswitch is not optimized for use in stomp mode, so I decided to build my own midi controller.
Here are the main features:
- All the parameters that are not directly accessible (Delay volume, intensity modulation, etc...) have their own settings on the footswitch.
- 3 channels are directly accessible (Clean, Crunch, Drive) the drive mode is selectable by an additional switch (Ultra or lead). Each channel has two preset levels (normal or solo) with an additional switch. This configuration is memorizable and remains adjustable in real time.
- I've added a TAP function to adjust the delay with the foot.
- I added the boost and noise gate function.
- I've added some convenient configuration memory functions. For example, starting from a clean sound with flanger, you can switch the drive (without flanger), switch back to clean and the flanger will be automatically reactivated.
- And finally, a filtered 9V source for my WhaWha generated from the amp power supply.

That's an interesting looking project there. What internal controller is it based on Bab_Art? As you have probably seen I have used Arduinos to control Marshalls in the past but that was using the Marshall in house comms lines which are very simple. A full on MIDI approach would be an interesting thing to play with.

The electronic board was designed especially for this application with DesignSpark. It is based on a Microchip PIC18F4520 microcontroller which contains everything you need for this application:
- An UART for the MIDI interface
- Logic inputs/outputs for switches and LEDs
- Analog inputs for potentiometers
- EEPROM memory to save some configurations
the board is supplied by the GM36 power supply.
The embedded software has been developed with the Microchip environment (MPLab X-IDE + XC8) .
The card is finally a classical MIDI controller, it could be adapted for any MIDI system as long as the control assignments are known.

The goal of this project was to create a system that its use is close to a set of many pedals with a certain interactivity between effects. I get something very compact on stage (I also use a very compact cab of my own making equipped with Eminence Gouvernor loudspeaker). it's ideal when space is limited.