Full Bucket Music has released The blooo, a free polyphonic software synthesizer plug-in based on the classic subtractive synthesis architecture. It's free and is available for Windows as a VST instrument plug-in.

Main features are:

• Up to 32 voices polyphony including portamento.
• Two band-limited oscillators including Ring modulation and hard sync.
• Four oscillator waveforms (sawtooth, pulse, sawpulse, sine) with shape control.
• Additional white noise generator.
• Two multi-mode four-pole filters (lowpass, highpass, bandpass, allpass, phaser) with resonance and panorama control.
• Three envelopes (ADSR) with exponential slopes.
• Three low frequency oscillators (LFOs) with tempo synchronization.
• It is written in native C++ code for high performance even on "lighter" systems.