Here's a peak at one of my side-projects. I've wanted to make a modular synth since I began making sense of synths a few years ago and wrote Caustic's subsynth.

Now that Caustic 2 allows for dynamic rack placement of machines, it also expands things for new machines. One of the suggestions that often comes up from gear-heads is the idea of a fully modular synth. I.e one you can make from pieces and connect however you wish. These monsters are great experimenting and learning.

I've been working on and off on this prototype since February, bits and pieces in between "serious" coding sessions for the app itself. The plan for this thing is to create a new machine to add to your rack in Caustic, but I'm also thinking of releasing it as a stand-alone iPad app to test the iOS waters.

But first I'd like to gather some feedback with a stand-alone PC/Mac version. No fancy installer this time. If you're on Windows, just unzip the package to somewhere on your hard drive and run the executable in the "bin" directory. Presets will be loaded and saved in a "presets" subfolder in the same directory where you unzipped it. If you're on Mac, open the disk image (.dmg) and follow the instructions in the provided text file. This my first ever app for Mac so it's possible I've screwed something up. Let me know if that's the case.

No formal instructions either so it's not for the faint of heart, but there are some basic "tutorial" presets to show you how it works. To place a new component, touch a grid square. To remove, select the X button and touch the component to remove. Toggle between the 3 views by using the top-center buttons. You can choose between "front", "rear" and "effects". Front is where the main dials are, rear is where connections are made and where signal gains can be tweaked. The keyboard's note signal comes in as "NoteCV" up top in rear view. The "gate" signal is automatic and hidden, envelopes will trigger on note press. There's a "mod wheel" that will appear if a cable is connect to its output. The app should work with MIDI keyboards on Windows, same as Caustic. Pitch and Mod wheels are hooked up, and so is volumeCC. Velocity is fed through an output signal next to NoteCV, but only varies when using a physical MIDI controller.

Try loading "too basic" for the simplest noise maker (that doesn't stop) then open "basic" to see how to control the oscillator with a simple attack+release envelope. Make sure you understand the concept of controlling oscillators with modulation envelopes and experiment from there. Connect components by dragging from an output connection onto an input jack. An output can go to many inputs but only one signal is allowed per input. Inputs start from the left and Outputs are generally on the right. It's possible to create feedback loops, the program won't complain, but there may be phase issues and horrible noises if you're not careful. Using feedback can be used to create powerful sounds from only a few components (ex: tiny trumpet uses its own output as FM modulation, disconnect the FM cable to hear what it would sound like without the feedback)

The "effects" view shows a multi-tap chorus, a delay and a reverb effects. These are chained top to bottom, connections are automatic.

There's no way to clear the rack of components so I've provided a blank preset to use for this purpose.

If you have no idea what any of this means but want to learn, SoundOnSound's Synth secrets is a great place to start learning (it's where I did!). Look at the earlier articles at the bottom, it starts getting more practical at Part 7.

Anyway, what I'm looking for right now is demo presets, bug reports and component ideas. Take your time, get to know the program and its components, and learn from the few presets that come with it. When you've got the hang of it and have made some cool-sounding ones, send them to me please. If suggesting new components, please describe whether it is required for an initial release or if it's just another "nice to have" block.

I need some demo material to ship with the app(s) and I'm offering a sneak peak in exchange for help getting it ready quicker. Submit any preset files to me via causticapp@gmail.com. Note that by sending me the files, you're handing over all rights to the work, though I will try to offer what I can to those who submit lots, at least a mention in the credits or something. Bonus points for using the velocity and mod wheel signals.

And to answer a question that might come up, I'm not sure when this will be in Caustic. It depends on how quickly I can get the next update out, because new synths are only coming in the update AFTER that. It also depends on how much demo content I can gather, on this and other new synths coming up. More on those later when it's time...

Ok, try it out, leave your comments below and let's hear those patches!

Caustic Modular Prototype - Windows XP / Vista / 7 (2.5Mb)
Caustic Modular Prototype - Intel Mac OSX 10.6 or greater (4Mb)