Build your own MIDI projects
Frequently Asked Questions.
MIDI & Music
MIDI and Music Information
MIDI saxophone

MIDI saxophone


This is a MIDI wind controller. The saxophone interface design uses a pressure sensor, 11 switches to produce an  output which is translated into volume sensitive MIDI data. The mapping of the switches (representing the saxophone valves, plus extras) is available. The breath pressure sensor should have the full voltage range (0-5V) to use for volume. Other switch mapping settings are available on request. The MIDI Channel is preset to channel 1. But other MIDI channels can be pre-programmed on request.



If you already have a suitable pressure transducer the project can be bought without the pressure transducer. It is also available with the pressure transducer included.




MIDI saxophone 

ITEM#: MIDIsaxophone

PRICE:  €65.00


pressure_sensor.jpg (23113 bytes) MIDI saxophone & Pressure


ITEM#: MIDIsaxophonePressure

PRICE:  €79.00







The MIDI saxophone interface utilizes:

  • An Arduino Mega board including a suitable pre-programmed microcontroller,
  • A 2.1mm power socket, and associated LED, 
  • A MIDI 5-pin DIN output socket,
  • A MIDI activity associated LED,
  • The switch mapping is available,
  • The circuit schematic is available,





The MIDI saxophone interface requires:

  • A 9 Volt battery or equivalent 9 Volt DC power source,
  • 20 momentary action (SPST) switches,
  • A Breath pressure sensor type MPXV5010G from Freescale Semiconductor (or similar type)
  • 3 10k Potentiometers for Vibrato control.


MIDI Saxophone Specifications:

11 momentary action switches inputs encoded to Saxophone Fingering Mapping,
An Octave up Switch,
An Octave down Switch,
A Horn Line Switch (Regular note plays along with a note that is an octave lower),
A Sustain Switch (Holds the notes being played like a sustain pedal)
5 Chord Switches,
A 2 Octave (25 note) keyboard MIDI Encoder. This would be used to play polyphonic chords,
Chord change and octave up or down based on if the octave buttons are pushed, 
The midi saxophone will be on midi channel 1,
The melody and chords channels are on MIDI channel 1, 

The octave switches transpose both the melody and the chords, 
The root note of the chords will be the same note as the melody note,
The lowest C on the midi keyboard is Middle C, MIDI note 60 and on MIDI Channel 2.
There are 3 vibrato control inputs: Vibrato Rate (cc#76), Vibrato Depth (cc#77) and Vibrato Delay (cc#78).



Circuit Schematic:

A circuit schematic of the MIDI saxophone interface shows the Input Switch and analog connections. The Arduino Mega circuit schematic is also available.


You can obtain a Freescale Semiconductor Breath Pressure sensor type MPXV5010G  (or similar type) from Digikey and other sources. 

Details of the MPXV5010G  pin connections are available. From the breath sensor, Pin 2 is connected to +5 Volt, Pin 3 is connected to Ground (GND) and Pin 4 is connected to the Analog pin A0, on the Arduino.


A plastic tube can be connected to the pressure sensor. It is probably a good idea to put a small pin-hole in the plastic tube near the pressure sensor to drain away moisture from your breath when you are blowing. The hole should be large enough to drain the moisture but not too large to affect the pressure sensor function.




Complete details of the MPXV5010G Freescale Semiconductor Breath Pressure sensor are also available. This is similar to the breath pressure sensor used in the Akai Electronic Wind Instrument (EWI). 



The MIDI IN and OUT connectors use  5-Pin 180 degree DIN sockets. Note that the MIDI IN/OUT wiring is polarised and the correct pins should be used.



An added feature in this design is a two octave 25 note MIDI keyboard encoder. The keyboard is designed as a 5x5 matrix and produces a MIDI output on MIDI channel 2. This keyboard encoder can be left with the wiring unconnected if required. ( It will not affect the rest of the MIDI saxophone's operation)


Power Supply: 

External  power can come either from an AC-to-DC adapter  or battery. The adapter can be connected by plugging a 2.1mm center-positive plug  into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector. 


The board can operate on an external supply of 7 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts.