Chapter 5
MIDI basics
The 1983 language every synth, drum machine and DAW still speaks.
After this chapter: “I can read what my gear is saying.”
5.1
MIDI carries instructions, not sound
MIDI (Musical Instrument Digital Interface) sends messages like "note 60 on, velocity 100" and "note 60 off". The receiving instrument decides what that sounds like. That is why one keyboard can play a Hydrasynth, an SH-01A and a software synth in Ableton at the same time.
A Note On message is three bytes: a status byte (0x90 plus the channel), the note number (0–127, middle C = 60) and the velocity (1–127).
5.2
Channels, CC and clock
There are 16 channels per MIDI connection, so one cable can address 16 instruments. Control Change (CC) messages move knobs remotely — CC 1 is the mod wheel, CC 74 is commonly filter cutoff. MIDI clock sends 24 ticks per quarter note so drum machines and sequencers stay locked to one tempo.
Connections come as 5-pin DIN, 3.5 mm TRS (common on compact gear like the Roland Boutiques) or USB, which is how most gear talks to a computer.
On real gear · Your rig
Exporting playground patterns as MIDI files and syncing with Logic Pro or Ableton is on the roadmap — it is not built yet. For now, use this module to read the bytes your gear already sends.
Experiment #5-1
Read a Note On
Decode the three bytes your keyboard sends.
- 1.In the figure, set CHANNEL to 1 and NOTE to 60.
- 2.Change CHANNEL to 10 and watch only the status byte change.
- 3.Change NOTE to 69 — that’s A4, the 440 Hz tuning note.
You should hear…
Nothing — MIDI isn’t sound. You should see 0x90 3C 64 become 0x99 when the channel moves to 10, the classic drum channel.
Doesn’t sound right?
Confused by hex? The binary line underneath shows the same byte bit by bit.
- TR-8S
- SH-01A
- Hydrasynth Deluxe
More recipes from this chapter
Full interactive panels with the same Manual & Panel layout — steps stay readable as text.
Check yourselfWhat does the status byte 0x93 mean?Reveal
Note On, channel 4. 0x9n is Note On; n is the channel minus one.
Next on the path
Stamp the recipes above, then either keep reading or step onto the gear route when you want a specific instrument’s panel language.