On Wed, 30 Aug 2006 07:32:30 GMT, (Don Pearce)
wrote:

(Incidentally I just had a proper listen to the original files, and
everyone was dead right - the hum didn't start 'til you hit the
groove. Still no idea how that could be, apart from it actually being
recorded on the disc which seems very unlikely)

Sorry to reply to my own post, but I have just thought how it could
be. The source of the hum was actually a transverse mechanical
vibration of the platter. While the stylus was skating about on the
flat part of the record it could not be transmitted into the needle -
the vinyl just slid around under the stylus. As soon as it was in the
groove, though, the stylus was grabbed, and any mechanical movement
was sent straight into the it.

Anyway - that's my theory. Anybody got a better one?

d

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