MIDI for Casio MT-90 with uniMatrix

This guide explains how to install a MIDI input in a Casio MT-90 keyboard. We use uniMatrix to interface the keyboard matrix and simulate key presses.
It is also possible to change instruments via MIDI program change messages and to select rhythms via MIDI CC.

ProgCh 0: Piano
ProgCh 1: Elec Piano
ProgCh 2: Organ
ProgCh 3: Oboe
ProgCh 4: Clarinet
ProgCh 5: Vibraphone
ProgCh 6: String
ProgCh 7: Elec Organ

CC 7: Rock
CC 8: Swing
CC 9: Walz
CC 10: Bossa Nova
CC 11: Slow Rock
CC 66: Sustain
CC 67: Casio Chord
CC 68: Start
CC 69: Stop

Installing uniMatrix

Use double sided tape to mount the uniMatrix board to the big IC on the MT-90 board. Then, solder the wires to the points shown in the picture below. The numbers are the uniMatrix I/O numbers. Do not rely on the wire colors in the picture, these might be different in your version of uniMatrix.
Solder the two power wires Vin and GND to the points shown.

Finally, drill a hole in the side using the drilling stencil provided in the kit, mount the MIDI socket using the two M3 bolts and plug it into the MIDI in connector of uniMatrix.

Using the uniMatrix configurator, load the configuration for MT-90 (right click, save-as) and send it to uniMatrix.

Congratulations, you can now play your MT-90 via MIDI !

Midi for Korg M-500 Micro-Preset – OrganDonor

WARNING!!!

Notes played via MIDI will sound ca 50ct lower than when played on the keyboard. You can compensate for this easily with the tuning knob of the synthesizer, but you of course can`t play the synthesizer via Midi and by hand at the same time.

Overview

The M-500 version of OrganDonor offers the following features:

  • Midi input
  • Optional learn button to set midi channel.

Installation

The installation is relatively simple, but does require basic soldering skills. You will need to drill a hole for the midi socket.
Installation instructions can be found in this PDF.

User guide

Setting midi channel and keyboard offset

If the optional learn button is installed, it can be used to quickly change the midi receive channel of organDonor.

Connect midi out of a computer or keyboard to midi in of organDonor. Make sure not to send any notes.
Press the learn button and while it is pressed send a midi note on any midi channel. organDonor will set this note as the lowest note of the synthesizer and use its midi channel. These settings are saved.

Playing notes

Send midi notes on the configured midi channel (see above)

More configuration

Alternatively you may configure a lot of parameters using our organDonor configurator.
We recommend using the M-500 config file as starting point
1.) Save the file on your hard drive via right click -> save as
2.) in the configurator press “Load configuration” and select the file

 

Create your own Brainstep samplepacks

There are several sample packs on Brainstep’s SD card already, however you can also create your own.
You will need up to 12 different samples with a maximum total length of 2.7s
You can use a lower number of samples and just duplicate them to use all keyboard keys. If duplicated, samples will only be saved once to save space.

Brainstep’s samples are rather LO-FI: 8-bit mu-law encoded with a samplerate of 24kHz.

To convert your samples into Brainstep’s sample pack format, you can use the web-based converter tool. If you want to be able to do this without an internet connection, just right click on the link, press “save as”. The html file works without being online.

Pearl FM-8 Fightman uniPulse installation

These instructions show how to connect the uniPulse to your Pearl Fightman in order to trigger the instruments via midi.

Instructions are generously provided by Matt Padden. Thank you!

All instruments can be trigggered:

36: Kick
37: Snare
38: Hat
39: Hat Pedal (off: closed; on: open) *
40: High Tom
41: Low Tom
42: Floor Tom
43: Crash
44: Ride

* Note that to achieve an Open Hat, the ‘Hat Pedal’ note must be held down while the ‘Hat’ note is played.

Installation instructions as PDF

Configuration file

MC-2oh2 firmware 1.1 news

Firmware 1.1 is a major update for our MC-2oh2 mod for Roland MC-202 synthesizers.

In addition to the already rich feature set, the update brings a live recorder with overdub, per-step probability, a swing/shuffle function and various small improvements.

Recording

MC-2oh2’s new recording feature can record from the keyboard or the output of the arp. An optional overdub feature allows corrections and ever-evolving patterns. At any time of the recording process, it is possible to switch into the pattern editor and modify the recorded pattern. Afterwards you can continue with the recording without having to stop the sequencer. This is perfect for playing and composing live and a lot of fun!

Per step probability

MC-2oh2 now features probability control of the gate and modifiers (accent, filter accent, portamento and noise) of each note. There are four different levels you can set:

0% (always off)
Low (33% probability by default)
High (66% by default)
100% (always on)

The levels for “low” and “high” can be set globally and even changed via midi CC.
When playing a pattern, the probability will be taken into account: If a note accent has a probability of 33%, every third time this note is played, it will trigger accent.

Swing

MC-2oh2 now features a swing / shuffle setting. Swing will delay every 2nd 16th note by an adjustable amount between 0% and 99%. Swing can be applied with any type of clock source: Internal clock, DIN-Sync, Midi Clock and trigger.

Performance shortcuts

Two new shortcuts are implemented to further improve MC-2oh2s live performance capabilities:
Pressing TEMPO now also shows an overlay with the state of each channel (normal, playing, arpeggiator, recording). With the press of a button you can quickly toggle between a started and stopped state for each channel. This allows quick and easy arrangements. Starting will always happen in sync.

Another shortcut helps to quickly change the channel: Press and hold CHAN and use the DOWN, NORM and UP buttons to select channel 1, 2 or the drum channel.

Screensaver

The new screensaver helps preventing burn-in of the OLED display. We recommend to activate it.

More

There are many more minor improvements and fixes.

Improving Juno-6 and Juno-60 noise

Here are some investigations and improvements on the Juno-6 and Juno-60 noise performance. We looked at both, the original CPU as well as our Juno-66 upgrade

Both, the original CPU and Juno-66 create noise on the output. You can hear that by not playing anything on the keyboard, select SAW as input waveform (as this seems to reduce the VCA bleeding) and pull the gain all the way up.
The noise performance can be improved by adding additional filtering to the 5V supply. In case of the SH-101 for example which has a similar problem, an additional 10µF ceramic cap close to the CPU worked very well.

Now, at least in the case of my Juno, the original CPU has actually a much louder noise ( I assume because it draws more current), as compared to Juno-66.
However, the noise is not focused on one frequency, but a broader spectrum. This is due to jitter in the original CPU processing.

Juno-66 on the other hand, produces noise with a dominant frequency content and hence might be more audible – even though actually quieter.

To rectify this, I have created a firmware update that introduces additional jitter to broaden the spectrum a bit. Note, however that a good solution would of course eliminate the noise via supply rail filtering.

Noise of the original CPU, while a key is pressed the frequency is a bit different.

With the same settings: Juno-66 firmware 1.29. I press keys and change the portamento switch. Note, that this is already quieter than the original CPU

Same setting: Juno-66 firmware 1.3 – jitter is introduced

Soldering an additional 10uF capacitor between GND and 5V on the bottom of the board across the CPU supply pins, improved the noise even further.

You can find the 1.30 firmware on the updater site.

Midi for Kawai SX-210 with OrganDonor

Overview

The Kawai SX-210 version of OrganDonor offers the following features:

  • Fully polyphonic midi input for all 61 Notes
  • Optional learn button to set midi channel.

Installation

The installation is relatively simple, but does require basic soldering skills. You will need to drill a hole for the midi socket.
Installation instructions can be found in this PDF.

User guide

Setting midi channel and keyboard offset

If the optional learn button is installed, it can be used to quickly change the midi receive channel of organDonor.

Connect midi out of a computer or keyboard to midi in of organDonor. Make sure not to send any notes.
Press the learn button and while it is pressed send a midi note on any midi channel. organDonor will set this note as the lowest note of the synthesizer and use its midi channel. These settings are saved.

Playing notes

Send midi notes on the configured midi channel (see above)

More configuration

Alternatively you may configure a lot of parameters using our organDonor configurator.
We recommend using the Kawai SX-210 config file as starting point
1.) Save the file on your hard drive via right click -> save as
2.) in the configurator press “Load configuration” and select the file

Korg Mini Pops 45 MIDI with uniPulse

This manual shows how to install uniPulse in a Korg Mini Pops 45 and trigger all 10 instruments via Midi.

The installation is fairly simple and only requires soldering a few wires and parts into place, as well as drilling a hole for the midi socket.

Trigger connections

Here we see the 10 trigger points for the various instruments. These are trigger outputs P1-P10 from uniPulse directly soldered to the trigger points.

In order to power the uniPulse you just need to solder the brown (V+) and red (GND) wires to the electrolytic capacitor shown in the picture.

Installing the midi socket

Installing the midi socket is simple. A drill guide is included in the kit. Any location is fine, we chose to install the socket next to the audio sockets.

Config file upload

After installing uniPulse, turn on the machine and make sure the LED on the uniPulse is turned on. This means it has power and is running.
Connect midi and use the config tool to upload the following configuration.

Config file (right click, save as)

have fun!