White Noise Audio have announced White Noise Additive, which, as its name implies, is an Additive synth, initially for Windows as a VSTi. The expected release date is December 2003 and it will cost $99 USD.

White Noise Additive Synth will allow you to visually create your own waveforms, spectral morphs and filters and it will apparently be "one of the most cpu friendly additive synths available"...

Features:

• 2 Spectral Oscillators.
• 128 partials per oscillator.
• Each oscillator has 128 "time frames" to allow sounds to evolve and change over time.
• FM capabilities.
• Ringmod, compression, reverb, distortion and chorus/delay.
• 2 Envelopes which can modify any parameter.
• 2 LFOs with multiple wave shapes, including arp patterns.
• Unison effects to phatten up any sound.
• 128 Band formant filter or noise spectrum.
• Can act as a 128 band vocoder.
• Formant filter has 128 time frames to allow changes over time.
• Formant Bias parameter also allows formant filter sweeps similar to sweeping the cutoff on an analog synth.
• Flexible mod section.
• On screen XY-Pad allows you to modulate parameters easily.
• Packaged with 128 presets plus dozens of waveforms and filters to make your own sounds with or create your own.
• Visually draw your own waveforms and spectral changes, similar to products like MetaSynth and Coagula.
• Draw your own filters.
• Average patch uses 20% for a 3 note chord on a 1.6 GHz P4 and can use more or less depending on settings like number of partials, oscs, and whether reverb and delay are turned on.
• Captures the unique and sought after sound of the Kawai K5000.
• A programmers heaven, this synth will let you create nearly any time of synthesized sound.