Image Line has introduced Harmless, an additive synthesizer designed to "do" subtractive synthesis.
Here's what they have to say about Harmless:
There are too many subtractive synthesizers already, often bragging about being virtual analog. This one is digital, and proud to be. Everything is fake, the tone generator, the filter & its resonance, the phaser, all performed on the harmonics, before partials are computed.
Now, how it's synthesized shouldn't matter after all, if the result sounds subtractive. But Harmless is more than a proof of concept, it allows fine control that wouldn't be possible through classic subtractive synthesis. Filtering and phasing can be assigned unusual shapes & slopes, something normally only possible through offline digital filters. Filter slopes can even be defined in Hz instead of octaves. Finally, you get control on each partial's frequency, creating timbres definitely impossible using common synthesis methods.
Image Line adds that their new synth is actually Harmless only in appearance.
See their site for audio examples.
Pricing and Availability
The Windows version is available now; a Mac version is planned. Through Dec 31st 2009, you pay what you think it is worth.