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Richard Clark

On Thu, 22 Feb 2007 14:19:22 GMT, (Bob Masta)
wrote:

My problem is
that I have only seen this described in theoretical terms with
simple block diagrams, leaving the exact coefficients, etc, as
"an excercise for the reader".

Hi Bob,

What you want to resource here are the printed materials available
(then) from the manufacturers of analyzers in the time span of 1980 to
1986 or so. Those would include Analog Devices or Hewlett Packard,
both of which had superb application notes that went to considerable
detail. The academic treatments of that era were mostly semester
based fluff introducing concepts, and not many at that. Industry was
the best source for actually grasping the concepts and implementing
the details. Soon after this period saw the introduction of DSP which
is a silicon processor equivalent of the IIR or FIR math (resource
Texas Instruments from that slightly later era for this discussion).

You did quite well in describing the "zoom" process. This hallmark of
the Real Time Audio Analyzers designed by HP 20 years ago was a long
time in coming. They had a 16 member design team working with a
million lines of Pascal code. It took them 5 years to develop the
product in contrast to the HP design cycle of 18 months. They also
had to design their own Pascal compiler.

I would recommend for reading those works from the Program Manager
Nick Pendergrass (Google: "nick pendergrass" fft).

73's
Richard Clark, KB7QHC