TubeOhm has released a free VST synthesizer, Alpha Ray.
It’s a 2-oscillator virtual analog that features sub-oscillator, three filters, FM & Sync, polyphonic overdrive, aftertouch modulation and more.
Alpha Ray is released as a free VST synthesizer for Windows. It’s fully functional as a synth, but you can unlock it for 5 Euro to enable additional effects.
See the TubeOhm site for details.