At 12:53 PM 2008-08-26, Eric Jacobs wrote:

>Weren't all those math formulas and standards the basis of the
>RCA test record?

Hello, Eric,

One of the two EQ implementations I looked into in depth was AME and
using modern components I had to shift the values slightly to create
a real-world graph like the one in Jay McKnight's paper on the
subject. It was an interesting tradeoff between matching Jay's graph,
the SPICE graphs from two implementations and real-world components.

The other EQ implementation that I looked into in depth was cassette
equalization, and it, too, is very imprecise and left that way.

I think it's safe to say that the real world does not follow precise
mathematical curves in many areas.

See: http://richardhess.com/tape/ame_equalizer_20040412.pdf
and
http://richardhess.com/notes/2006/05/17/cassette-equalization-the-4-db-ambiguity-at-16-khz/

Cheers,

Richard

Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
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