[music-dsp] audio filter and z domain

[Nigel Redmon]

Good job, John--you figured it out. (Of course you mean rz^-2--an 
obvious typo.)

>> H(z) = (m + nz^-1 + pz^-2)/(1 + qz^-1 + rz2)
>>
>> How do I relate m, n, p, q, r to the above filter coefficients a(k), b(k)?
>> Ie.  how do I relate z-domain to time domain?
> 
> Hello all,
> I am answering my own question and would like to see if it is correct.
> From inverse z-transform, I can write
> y(n) = mx(n) + nx(n-1) + px(n-2) -qy(n-1) -ry(n-2)
> which implies
> b(k) = {m,n,p} and a(k) = {q,r}
> So the coeff. of the frequency response in z-domain are indeed the filter
> coefficients in time domain.  Is this correct?
> John