MidiPipe is freeware and comes with no warranties. MidiPipe can be useful in a music studio or live on stage to route, map, filter, convert, display, input and output MIDI messages in real-time. Latest version of MidiPipe is an unsigned 64-bit Universal Intel+ARM app that runs on macOS 11.0 or higher.


MidiPipe V1.7.3 (2024-06-08, 64-bit Universal Intel+ARM, macOS 11.0 or higher)

MidiPipe V1.6.3 (2021-12-25, 64-bit Universal Intel+ARM, macOS 10.12 or higher)

MidiPipe V1.4.6 (2012-05-05, 32-bit, Mac OS X 10.3.9 to macOS 10.14)

What to do if MidiPipe won't start

MidiPipe is an unsigned app, so macOS Gatekeeper will prevent it from launching. How to override Gatekeeper is explained here.


Click on a tool in the "Tools" list (left side) to see it's parameters. "Drag&Drop" or "Double Click" a tool in the "Tools" list in order to put it in the pipe (right side). Tools in the pipe can be reordered via "Drag&Drop". MIDI messages "flow" from top to bottom through the pipe. A pipe can have several inputs and outputs. A message arriving at an output will be copied to the output and then continues "flowing" through the pipe (if there are additional tools after the output). In order to edit parameters of several tools at once, it is possible to open a panel for each tool by double clicking it in the pipe list.

MidiPipe FAQ



•  MIDI In - connects a MIDI input to the pipe

•  MIDI Out - connects a MIDI output to the pipe

•  AList - outputs messages to the screen

•  Message Converter - converts messages from one type to an other

•  Delay - delays the time for when the message is scheduled

•  Transpose - transposes note to multiple keys, set velocity, delay and channel for each

•  Message Filter - filters by messages

•  Channel Filter -  filters by channel

•  Channel Router - routes channels

•  Keyboard Split - moves note on/off messages above/below a split point to a different channel

•  Randomizer - randomly changes any parameter value(s) of any channel message(s)

•  Keyboard - play a on screen keyboard with your mouse or keys; will display arriving messages too

•  MicroTuner - apply different scales

•  Duration - add a delay between Note On and Note Off messages

•  Set - set any parameter value(s) of any channel message(s) to any value

•  Control Split - inverse, limit, scale, fade in/out, route and map MIDI controllers

•  Control Slider - simple slider for control message input

•  AppleScript Trigger - use the power of AppleScript to implement everything you want

•  (N)RPN Mapper - map (N)RPNs

•  Velocity Modifier - scale, shift, clip and filter the velocity of Note On and Note Off messages

•  SMF Player - plays up to 128 MIDI Files; handles Song Select, Start/Stop/Continue messages

•  Key Mapper - map keys

•  DLS Synth - user interface for Apple's DLS Synth

•  Message Factory - trigger your own messages with static and variable data bytes

•  Double Filter - filters identical messages

•  Monophonic - make monophonic

•  Toggle - toggle between two defined values