Helm, a polyphonic synthesizer with realtime modulation feedback, has just reached beta stage. Helm is available in a number of forms, including a standalone client as well as being able to run as an LV2 plugin.

Helm has a subtractive synthesizer engine with three oscillators with 15 anti-aliased waveforms, cross modulation, 32 voice polyphony, a low-pass, high-pass, band-pass, notch, low-shelf, high shelf and all-pass filter.

There is also a formant filter, stutter, delay and reverb effects, patch browsing, MIDI learn and more.

You can check out the project over at tytel.org with the projects source code available on Github.