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90degree phase shifts
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Les Cargill[_4_]
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90degree phase shifts
hank alrich wrote:
Les Cargill wrote:
hank alrich wrote:
Les Cargill wrote:
wrote:
I'm guessing you all probably know why I need to create one of the
above - to trick a Pro Logic Surround decoder.
Problem is, I know what a 90 - and 180 - deg phase shift looks like
on a pure sinewave, but how to I achieve 90 degrees phase shift on
"real world" material - a clip of ducks quacking or a 1890s
locomotive roaring by? There is no simple wave - ducks, trains, and
of course music - are anything but simple!
I have no idea how you do it in analog or in real time. But a
Hilbert Transform will provide a very good 90 degree phase
shift.
I think that there are real time and analog versions of them;
I only know how to do to in the not-real time way.
As to the surround decoder - turn that off and do it
stereo. People still know how to do that.
I'm wondering why one would want to trick a Dolby PLS decoder.
I tried real hard not to think about that.
Sorry I mentioned it.
Mentioned what?
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Les Cargill
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