Getting your hands dirty...

[comrade_zero]

This post is for all of you members (or lurking guests) out there who:
a) already own an Arduino
or
b) are thinking about getting an Arduino
and want to know:
"What synthesizer applications can I reasonably make with this development board?"
In other words, I've got this microcontroller, now what am I gonna do with it?
So, let me offer a few project suggestions, hints, really, based off of a few projects I've built and played with, and some that I'm in the process of prototyping at the moment.

1) MIDI in functionality. Arduino can handle MIDI reasonably well, and while not a trivial undertaking, it is certainly viable. You will need to build a simple circuit (optocoupler etc.) but it is well worth the effort. Using a simple sawtooth VCO (the super-simple vco from Nicolas, here on the forum) and MIDI in, you can build a simple mono bass synth. (Add a simple sallen-key filter and an LED/LDR attenuator for some resonance and AM, and you have a nice little synth!)

2) Create a DCO. You can use the "tone" command to output square waves at a certain frequency. You can play with transistors and capacitors to create sawtooth waves based on your square wave. You can build a simple rudimentary DCO in this fashion. (I haven't gotten this one 100% yet, but check out Francois Best's site and his mixed control oscillator.)

3) Wavetable oscillators. There are a few projects around the web. Not for beginners, but well worth exploring.

4) Automated filter. Using LED/LDR combinations instead of OTAs in a wasp-style cd4069 resonant filter. Use pots and analog inputs to control attack/realease times...

5) Powerful analog step sequencer (currently in development). Use the Arduino as the "clock" to control two binary-to-decimal counters hooked up similar to the baby-10 sequencer. Allows for 16-step sequencing with voltages up to 15v.

soooo, what else are you using your Arduino for? I've seen a lot more activity surrounding it recently, which is great. The more project options the better.
Anyway, I hope this is food for thought,
c_z

[elmegil]

My first (and so far only) project was MIDI -> CV.

I have ideas (posted here: http://electro-music.com/forum/topic-54108.html) for a more complex MIDI -> CV scheme, and I think using SPI I can still use Arduino. But that's currently in my backlog . As is potentially working with mrkva's auduino ideas.

[garcho]

[Mdashdotdashn]

Right now I've used it exclusively to build little synth engines.

My first attempt was to do an engine for the late critter and guitarri arduino pocket piano.

http://www.marc-nostromo.com/?page_id=14

And then moved on to 'augmenting' the midivox with LCD & potentiometers.

http://www.marc-nostromo.com/?p=134

I also have my hands on a SJS-1

http://devsound.se/2012/sjs-one

But didn't have too much time to spend my time on it.

Right now, I think I'll try to externalise the filter so I don't have to compute it in the arduino (and it'll be an interesting exercise to control the filter from there) and get more room for oscillator computations.

/M