Got taste of the Raspberry Pi this, although it does actually beat it on price, the BassBoy from Mikro Elektronika is a mono bass synthesizer with simple wavetable synthesis and a low pass filter with drive. Parameter control is purely over MIDI and appears to be geared towards the 303 type of Accent and Slide type of stuff. Additionally you can control these parameters:
Midi CC 7 Volume.
Midi CC 53 Filter Pre-Gain.
Midi CC 54 Cut-Off.
Midi CC 55 Resonance.
Midi CC 56 Envelope modulation.
Midi CC 57 Envelope Decay.
Midi CC 58 Accent.
Midi CC 59 Distort Gain.
BassBoy is a monophonic digital MIDI controlled bass synthesizer. Device receives all information via MIDI input (mono connector).
The author of this device, Aleksandar Krstic, had a childhood dream of bulding his own version of one brand of then famous MIDI synthesizer. As he learned more and more about sound processing, he also developed interest in programming. When the worlds of music and programming met, he started building great signal processing algorithms. And soon after, idea for BassBoy was born. In order to utilize each and every single CPU cycle, Aleksandar wrote the firmware in plain assembly. This is why BassBoy runs smoothly even on 8-bit ATXMega32D4 microcontroller.
Sampling frequency is 31.25KHz which generates audio range up to 15.625Khz. Although it's based on 8-bit processor, the signal processing inside the unit is 16-bit.
The unit is mono, and 6.35mm jack is also used as carrier for the circuit board itself.