On Wed, 15 Feb 2006 17:00:11 -0500, Walt wrote:

Then either leave well enough alone, or invert both L & R. I'd just
leave it. Except in rare circumstances, a polarity reversal is not
audible, and for all you know the original LP may have been released
with the polarity reversed.

//Walt

Absolute polarity isn't audible from recordings under any circumstances.
Its an audiophile myth. I took part in double blind tests of this effect
on two occasions where several 'golden ears' were convinced they could
without a doubt hear absolute phase, only to discover that statistically
their ability to detect it were no better than tossing a coin.

--jeff