SCB-1 is a free software synthesizer developed by Fred Welsh. Available format(s): VST for Windows.
Features:
- Amplitude response and filter slopes based on the averages of ten commercial synths.
- Settings of each parameter clearly displayed.
- 2 oscillators: square/pulse, sawtooth, triangle, with sync and white noise source.
- 12 dB/24 dB lowpass filter with ADSR envelope.
- LFO syncs to host or runs independently.
- Stereo delay, chorus, stereo broadening, and frequency spectrograph.
http://www.synthesizer-cookbook.com/