The Arduino is a very versatile module, here it is being used as a miniature stand alone musical synthesizer. A musical instrument board is plugged into the Arduino board and offers 25 multiplexed keys or two octaves, four variable resistors that serves as controls and another one as an output level, LED for power monitor, reset switch, an IC for converting the digital signal to analog and an RCA audio jack. The Adriano module board with a strong AVR processor is equipped and powerful enough for a broad spectrum of synthesized sound. Experiments show that it is capable of additive / wave-table synthesis, frequency modulation, ring modulation and sampling, polyphony, different kinds of arpeggiator. The whole package is supplied by the Arduino’s USB port for a hustle free experimentation.

The board can easily fit into a panel material 1/8” and you can use wood, plastic or metal for the 1/2 round keys. Only your imagination can limit the enclosure or feature you would like to mount it to. The sound produced are good enough for experimenters and hobbyists. FM synthesizer and Poly Octave Arpeggiator also create great sounds.
The kit needs to be soldered the components assembled to the printed circuit board. Be sure that the components are welded on the proper side of the PCB especially because it is a double sided board. The underside of the board has white paint printed with the information.

The ICs should be oriented with the notches on the sockets line up with that of the socket. The pins of the ICs must fit on the sockets. Then insert the capacitors and resistors are to be soldered in vertical orientation. Next is the header pins, RCA jack, tactile switches, LED and potentiometers. Make sure both sides of the PCB are soldered for added strength.

The circuit needs 9 VDC center positive power adapter or switch the power header of the Arduino to 'external.'

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