Support & FAQ
How to connect MIDI devices, look up chords, and use Chordindex.
Connecting MIDI Sources
Chordindex automatically listens for note inputs so you can play immediately. You can select your preferred input method:
- USB MIDI: Plug in any class-compliant MIDI controller using the appropriate adapter. The app will detect it automatically.
- Bluetooth MIDI: Pair the keyboard with your device first — in iOS Settings or the system Bluetooth MIDI browser — then choose it in the app's MIDI source picker. Once paired, it works exactly like a wired keyboard.
- On-Screen Instruments: No hardware? No problem. The built-in on-screen piano and interactive fretboard work completely standalone to input and identify chords.
Looking up chords
If you don't know how to play a chord, you can use the reverse lookup feature. Type a chord name directly into the app (for example, "Cmaj7" or "Fsus4"), and Chordindex will instantly show you its required tones, alternative names, and correct voicings across the piano, guitar, and grand staff views.
Common questions
My keyboard went silent as soon as I connected it
That is the keyboard, not Chordindex. Many digital pianos switch Local Control off automatically when a USB host is connected, which disconnects their own keys from their own sound engine. Turn Local Control back on in the instrument's settings and it will sound normally again. Chordindex only reads incoming notes — it never mutes, routes, or captures your instrument's audio.
Chordindex itself doesn't make any sound
That is by design: it names what you play rather than playing it. If you want to hear the notes you tap on the on-screen piano, open the MIDI source picker and turn on Preview sound for a simple synthesized tone.
The chord name disappears the moment I lift my hands
Chordindex names the notes that are sounding. Tap Pedal to hold them, or use a sustain pedal on a connected keyboard — the app follows sustain (CC64). Clear releases everything. The last chord you played also stays named on screen once the notes stop.
The notes are spelled with sharps and I want flats
Set the concert key in the top bar. Spelling follows the key you choose, so the same notes read as D♯ or E♭ depending on where you're playing.
My keyboard isn't in the MIDI source list
Reopen the source picker to rescan. For USB, check that the cable is a data cable and the controller is class-compliant. For Bluetooth, confirm it is paired at the system level first. With nothing connected, the list shows Demo Keyboard and the on-screen piano and fretboard keep working.
Still need help?
If you encounter issues or have feedback, please reach out.
Email nguyen.nguyen@techartvn.com