Bluetooth Low Energy MIDI (BLE-MIDI)

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Bluetooth Low Energy MIDI (BLE-MIDI)

Also called BLE-MIDI, MIDI over Bluetooth Low Energy, RP-052.

A GATT-based transport that packs standard MIDI 1.0 messages, with millisecond timestamps for jitter correction, into Bluetooth Low Energy characteristic writes so a keyboard, pedal or controller can talk MIDI wirelessly to a phone, tablet or computer. It sits behind most modern wireless MIDI foot controllers, keyboards and BLE MIDI interface dongles used in live performance rigs.

Audio controlPaid specMIDI AssociationReported

Stewarded by MIDI Association (MMA/AMEI).

Control Small, urgent, must arrive

Small messages that either repeat constantly or fire once. Bandwidth is almost never the problem.

What kills it. Latency and loss on the messages that fire once. A repeating level survives a dropped packet; a GO does not.

The four flows, and why the model is worth having →

What goes wrong

BLE packets are capped at the negotiated MTU minus 3 bytes (typically only 20 bytes by default), so dense note bursts, chords or sysex fragment across multiple BLE writes; both sides need to negotiate a larger MTU to avoid this becoming audible as timing jitter.

The spec's own millisecond timestamp header only claims jitter "comparable to the USB Class Specification" and explicitly warns that wireless delivery delays can occur unexpectedly at any time, so BLE-MIDI is not a guaranteed low-latency transport the way a DIN cable or wired USB is.

As of 2026 the official BLE-MIDI 1.0 spec PDF is gated behind a paid MIDI Association SysEx ID ($240 one-time) or Corporate membership rather than a free download on midi.org, even though implementing the protocol itself is royalty-free.

Open source implementations

Arduino-BLE-MIDI — C++, MIT

Typical use

Wireless MIDI controllers, foot pedals and keyboards connecting to tablets, phones or computers in performance rigs
iOS/macOS Core MIDI Bluetooth peripheral pairing for stage-side control surfaces
Point-to-point wireless MIDI links replacing a DIN cable run where routing 5-pin MIDI is impractical

Sources

MIDI over Bluetooth Low Energy (BLE-MIDI) — spec listing, gated behind SysEx ID/Corporate membership — MIDI Association primary
Specification for MIDI over Bluetooth Low Energy (BLE-MIDI) Version 1.0, November 1 2015 (MMA/AMEI RP-052; service/characteristic UUIDs, timestamp encoding, MTU limits) — MIDI Manufacturers Association / AMEI primary
MIDI Bluetooth — Core MIDI documentation — Apple Inc.
Membership tiers and pricing (Individual free / SysEx ID $240 / Corporate from $600, spec access levels) — MIDI Association primary

Understand the mechanism

How software talks to software Numbers that stand for signals

Something wrong, or missing?

Known gaps on this entry: default_ports. If you can source one of them, that is a ten minute pull request.

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