xoxos has released two physical model based VST Instruments for Windows based on Chris Kerry's "Feedback Delay Network" SynthEdit modules.

Pling is an implementation of the karplus-strong model using Chris Kerry's feedback delay network modules. The top panel models the pick impulse and the middle panel indicates string characteristics. Two sympathetic resonance models are among the modulation destinations.

Surface also uses Chris Kerry's feedback delay network module to produce surface model resonances based on x-y pad settings. Timbral behaviour within the model is similar to hand drums. Use of the 'vary' parameter allows MIDI loops to attain an organic variation.

Pling is free and Surface costs US$10 (Demo available).