Hv Synth Design Total Brass VSTi 1.0
Physical Modeling
There are several methods. The most common are waveguide and model synthesis and, what I call, real physical modeling. Waveguide is a construction of a chain of delays and filters in a feedback loop. Model synthesis is a configuration of mass/spring/damper blocks. Real physical modeling can be created after scientific research to the properties of an instrument. And then ‘rebuilding’ this in complex mathematical formulae (like Pianoteq from Modart).
Eclectic Acoustic synthesis
I use a complete other self developed method. I have called it Eclectic Acoustic Synthesis (EAS). With Eclectic I mean that I use everything to improve the sound quality: filters, distortion, math functions, multiple feedback loops, etc. So it is not 'real' physical modeling. At the other hand I have modeled all the different parts of the brass instruments separate, and then connected them in multiple feedback loops. Interesting enough the lower the tone, the more harmonics (as in real instruments). This is the reason - with some extra extra engines - that I was able to create low and high brass in one VSTi. Furthermore Total Brass is really a virtual instrument: when you blow a trombone very high, then you get the sound of a very small trombone (alto trombone?) 
