[78-L] A novice-y type Purple OKeh question

[Andrea Walsh]

Hello all,

I have recently (on a whim) been playing all my 78's that were issued on
Purple OKeh, and I was planning on posting them to my blog.  While
listening, I notice some are muddy sounding, or at least sort of far-away,
and others are really clear and the sound is much more defined.

This may seem like a stupid novice type question, but what are the
differences?  Are some of these dubs and others original?  I have been
listening to everything from country and western swing to jazz and swing,
novelty, gospel, rhythm and blues and blues.

I read what Rust has to say about the purple issue OKehs in the American
Record Label Book, that the revived OKeh series of 1940 and after have
normal CBS series masters, but what does that mean?  Is, for instance the
recording of Bessie Smith doing "Gimme A Pigfoot" (OK 6893) a dub of a
Vocalion and say, Blind Boy Fuller doing "Step It Up And Go" (OK 05476) an
original?

How can one tell an "original" recording, if there is such a thing?

I am confuzzled.

Thanks in advance--

Andrea