Formanta Maestro MIDI kit A03.1 and Resonance MOD
Retrofit receives MIDI notes and triggering circuit boards the same as you playing on the keyboard with hands and triggering key contacts. It controls only the keyboard, all other controls in your hands and you still can play with the keyboard at the same time when it controls with MIDI.
Welcome to the metric system zone. Here we work with precision things and all dimensions are metric. 1" = 25.4mm.
Installation:
To your good usability experience select the friendly place to mount the LED indicator, MIDI connector, button and PCB. Best place for PCB can be on key contacts boards as sandwich, using genuine screw holes. Or just wrap board with bubble material and place inside. The MIDI jack and pushbutton can fit near jacks at rear panel. Activity indicator can be placed on top panel. Drill all holes that required and mount connector, Indicator and button of course before soldering wires.
Drill dimensions:
MIDI jack (DIN5) = 18mm.
LED holder = 6mm.
Push button = 12.5-13mm.
Be careful with drilling hole for push button, it have so small range to get hole too big. See below dimension ranges from their datasheet. Drill a bit less and file it to fide fitting.
Board dimensions and distance between screws:
Dimensions 102x50mm. Height ~14mm with inserted connectors.
Holes diameter 3.5mm.
Mounting outline and hole drills draft for board example sticker paper included for both boards.
Do not allow the board to bend, it can break the board.
All ribbon cables are 90cm long, enough for placing all connections and you can cut extra length.
This picture shown first (1) pin/wire on all connectors: J1-J4 should be open.
J5 should be close if already not.
The next picture shows the pinout for 14 and 8 wire ribbon cables. And also pin number of wires: Same orientation when board facing to you.
More visual wiring:
You will need to connect wire 4 (GND) with LED and button. All other wires in this kit required only one point of soldering.
(7) V+ and (8) GND should be soldered on the next points:
One small important thing - use hot glue to fix inserted connectors to protect from disconnecting them during vibration when you ride on tour. Also fix wires strong. Do not leave them holding only on soldering joints.
Process for set MIDI channel: User operations
Stop all MIDI traffic.
Push and hold the LEARN button for a 1-2sec. LED will blink fast four times and stay ON to wait for MIDI messages at one of 16 channels.
Send any note on the MIDI channel which you want for this synth.
When the synth receives MIDI messages, LED will blink fast four times and turn OFF. It indicates that channel was received and saved. Then will ON with every NOTE ON messages on the selected channel.
Now the channels saved to memory and will never change before you initiate the settings process again.
In case of PANIC, or you want to exit from settings - Short push the LEARN button.
At moment when synth power on, all keys will be sound less a half second. If on this moment MIDI commands will received on saved channel it can be cause of panic.
Last update: 23 March 2026.
