Implementation Idea

Apply TIIR ``alternate and reset'' idea

to the unstable conical subsystem

• Cone is not truly FIR $\Rightarrow$ $t_{60}$ replaces FIR length
• When cylinder is closed-ended, cone traveling-wave components increase without bound $\Rightarrow$ must switch out and reset the entire cone assembly (scattering-junction filter $R(z)$ and cone's entire delay line)
• According to simulations thus far, cylinder waves are well behaved and do not need to be reset (no general proof yet)

Basic Principle

Periodically reset any subsystem containing a canceled unstable pole at intervals greater than or equal to the $t_{60}$ for that subsystem