> Hans, SM5KI, mentioned phase distortion in filters. According to the
> experts, the ear is not sensitive to phase distortion. There's been lots
> in both the acoustics and the medical journals on that, but personally,
> I'm still not totally convinced. Of course, for processed speech in
> transmitters, where some flattening of the envelope takes place,
> differential group delay will alter the wave shape, so perhaps that's a
> special case.
>
I've been listening to narrow filters all my life, and I never notice any
problems. Maybe someone can explain to me how phase distortion
affects a CW signal?
Even on SSB, phase distortion is minor. I doubt anyone could hear
the difference in a blind test. The RF phase delay is not the same
effect as phase delay in an audio system.
Next thing you know we'll all be worried about harmonic distortion
at RF! I had a guy tell me he was going to build a push-pull amp to
improve his SSB signal by reducing harmonic distortion. I told him
to be sure an use oxygen free copper with gold plated connectors.
73, Tom W8JI
w8ji@contesting.com
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