Roland RS-505 MIDI kit installation manual RevA04.0
This retrofit only for key triggering through MIDI. Note ON/OFF only.
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 select the friendly place to mount the LED, MIDI connector, button and PCB. DIN5 jack and pushbutton can fit near mains cable at rear panel. Activity indicator can be placed on top panel near the power switch. Drill all holes that required and mount connector, LED and button before soldering wires of course.
Drill dimensions:
MIDI jack (DIN5) = 18mm.
LED holder = 6mm.
Push button = 12.5-13mm.
Be careful with drilling hole for button, it have so small range to get hole too big.
Board dimensions and distance between screws in millimeters:
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. Reset "Panic" button is not included in the kit. If you prefer to install it part number is E-Switch RP3502MABLK
This picture shown:
First (1) pin/wire on all connectors. First wire will be start from this side.
J2, J3, J4 jumpers that divide common rails for every octave separate or split.
For Roland RS-505 they should be closed
Bottom side jumper J5 should be open, J6 closed.
The next picture shows the pinout for X6 connector ribbon cable and pin number of wires: Same you can see on bottom side of PCB for more convenience. Ribbon cables pinout for better visual understanding. Even if wires go out on opposite side of connector, it still on same sequence - wire 1 at down or right on face to you. DIN5 shoved from legs side.
Connection at power supply: Wire 7 (V+) should be soldered point between collector Q1 and resistors R2, R3. On schematic below is shoved where it, wire 8 (GND) to any ground.
So, now is time to soldering key contact wires: Here is pinout legend for 14pin ribbon cables.
X1 unused on this synth, but still active and have range C3-B3. It can be used for some mods that not described yet.
At this point your brain can blow. Let me explain:
Find key contact spring for note (C) on the first octave and solder wires from the BLUE connector. Starting from wire 1. When you finish it, your last wire will be 12 and note (B) on this octave. Repeat it for others octave. On last octave RED solder wire 14 to last key C, wire 13 to common key contact rail that is for from you. Skip else wires that marked on table "skip".
Bass octaves key contacts Have same pinout algorithm.
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
1. Stop all MIDI traffic.
2. To teach with which MIDI channel synth will work - push the black button (LEARN) LED will blink two times and stay ON to wait for MIDI messages at one of 16 channels. He will in OMNY mode.
3. Send any note on the MIDI channel which you want for this synth.
4. When the synth receives MIDI messages, LED will blink five times and turn OFF. It indicates that channel was received and saved. Then will ON with every NOTE ON messages on the selected channel.
5. Now the channel saved to memory and will never change before you push LEARN button again and starts settings process again.
In case of panic: Stop MIDI traffic on working channel. Push reset button (if installed) or turn ON/OFF the synth. For mode button control is enough to send short MIDI note once for enable/disable.
At moment when synth power on all keys will be sound and buttons might be randomly switched. If on this moment MIDI commands will received on saved channel it can be cause of panic..
Last update: 14 January 2026.
