At very high pitches, the delay-line length used in the string may become too short for the implementation used, especially when using vectorized module signals (sometimes called ``chunks'' in place of samples ). In this case, good results can be obtained by replacing the filtered-delay-loop string model by a simpler model consisting only of a few parallel, second-order filter sections or enveloped sinusoidal oscillators, etc. In other words, modal synthesis (§8.5) is a good choice for very high key numbers.
Force-Pulse Filter Design
Commuted Synthesis of String Reverberation