It’s been a while since anything was mentioned about the upcoming ST4 synth. So, here’s a little post to show the progress of the last months.

The ST4 wood board being operated.

For those of you not in the know, the ST4 is a multi-channel synth that specializes in rhythm. It’s a hybrid digital/analog system that offers direct control over each track and has a powerful built-in step sequencer. It can do sampling with its on-board mic or from an external source. Samples can be manipulated into arbitrary waveforms, but also standard saw, square and sine waveforms may be used. Noise generators, a wealth of envelopes and per-channel multi-mode filters allow for powerful percussive sculpting.

Our goal is to make this as much a stand-alone system as possible. There’s the usual MIDI connectivity, but there’s also the built-in step sequencer on a large display with full USB keyboard and mass storage support. This makes the ST4 a unique device and as much a studio work horse as something you can take along to your friends or use on stage. The analog VCFs and VCAs give it a warm finish. It’s a Tasty Chips synth: high character and fun to use. 🙂

The current prototype is nailed to a wood board for stability and now has its own AC/DC converter PCB. Almost everything is now on PCB’s (8 in total) and the display is fully integrated into the system. TODO: photo

The GUI is getting more mature by the day. There are little animations for when knobs are turned, the editor allows block functions for copy/paste, transpose, panning, etc. There’s still a lot to be done, but progress is rapid. TODO: anim gif

In terms of performance we can say that the audio quality is as it should be. Also the graphics performance was radically boosted (basically an optimized and specialized version of the UTFT library), and the USB Host driver was completely turned into statemachines, to allow decent multitasking without blocking waits. If anybody is interested in such code for the Arduino Due, just mail us!

There is one performance issue left, however. The potentiometers are spiky, which causes all kinds of glitches in the system. There are ways to reduce this, but we probably need some more weeks to clean this all up. Electro-Magnetic Compatibility (EMC) is a huge can of worms!

To summarize, the ST4 looks like it’s going to be a great product. We aim to release it before Christmas and we might do a Kickstarter before that time.