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MIDI Channel Filter


MIDI Channel Filter


The MIDI Channel Filter can be used to reduce MIDI throughput by removing MIDI System mesages. Also it allows one channel to operate a particular sound module/synthesiser, while filtering out the other MIDI channel data.




*Click to Enlarge*


MIDI Channel Filter


PRICE:  €50.00







The MIDI Channel Filter unit utilizes:

  • An assembled, built and tested Arduino board including a suitable pre-programmed Atmega168,
  • A 2.1mm power socket, and associated LED, 
  • A MIDI detection LED,
  • A 4-way DIP switch, which selects the MIDI channel at power-on, shown in table 1
  • A 150mm wired MIDI 5-pin DIN input socket,
  • A 150mm wired MIDI 5-pin DIN output socket, 
  • The circuit schematic is available,.



The MIDI Channel Filter  requires:

  • A 9 Volt battery or equivalent 9 Volt DC external power source, or USB Connector.




     *Click to Enlarge*

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.






The unit detects the incoming MIDI data and if the MIDI channel corresponds to the DIP switch MIDI channel setting, when a corresponding MIDI channel event  is detected, then the MIDI data is transferred to the MIDI output.

However if MIDI data from another MIDI channel is detected it is filtered out and it is not transferred to the output.

Also any non-channel events are filtered out. So any System Common, Realtime or Exclusive events are ignored.



MIDI Specification: 

 The MIDI Channel Filter commands are all channel (1-16) dependent. The system will also work with MIDI running status.



DIP Switch Selections



4 3 2 1
on on on on 1
on on on off 2
on  on  off on 3
on on off off 4
on off on on 5
on off on off 6
on off off on 7
on off off off 8
off on on on 9
off on on off 10
off on  off on 11
off on off off 12
off off on on 13
off off on off 14
off off off on 15
off off off off 16

Table 1 MIDI Channel



Power Supply:

The  Arduino/Freeduino etc. Diecimila can be powered via the USB connection or with an external power supply. The power source is selected by the PWR_SEL jumper. To power the board from the USB connection, place it on the two pins closest to the USB connector, for an external power supply, the two pins closest to the external power jack.


External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) 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. A low dropout regulator provides improved energy efficiency.


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.


Note that with the Arduino Duemilanove or Mega the power input selection (USB/EXT.) is automatically selected.