... Smith¹

D. Rocchesso is with the Centro di Sonologia Computazionale, Dipartimento di Elettronica e Informatica, Università degli Studi di Padova, via Gradenigo, 6/A - 35131 PADOVA - ITALY, Phone: ++39+49.8283757, FAX: ++39+49.8287699, E-mail: roc@csc.unipd.it. J. O. Smith is with the Center for Computer Research in Music and Acoustics (CCRMA), Music Department, Stanford University, Stanford, CA 94305, E-mail: jos@ccrma.stanford.edu.

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... matrix,²

While papers on this subject speak of unitary feedback matrices $U\in{\cal C}^N$ defined by $U^H U = I$, where $U^H$ denotes the Hermitian transpose of $U$, all practical applications thus far appear to be confined to orthogonal matrices $U\in {\cal R}^N$.

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... verified³

using the eigenvectors ${\bf e}_0^T = [1,\ldots,1]$ and ${\bf e}_k^T = [1,\ldots,1,\underbrace{1-\Gamma_J/\Gamma_k}_{k^{\mbox{th}}},1,\ldots,1], \, k=1,\ldots N$

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... impulse.⁴

Since we are discussing discrete-time systems, the term ``impulse'' means the same thing as ``unit sample pulse.''

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