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Re: Minidisk data transfer and bat recordings

Subject: Re: Minidisk data transfer and bat recordings
From: Walter Knapp <>
Date: Sun, 25 Jan 2004 11:13:28 -0500
From: Aaron Ximm <>

> The gift is that if you edit the waveform in a greater than 23 or 32 bit
> "space," you can in a straigthforward way exactly restore the un-rolled
> state -- in the example above, simply add the extra "1" back on.
>
> The result is that your gear is effectively > 16 bit resolution (in
> representation), as long as the "overs" are only on momentary transients
> (and hence identified contextually).

Actually with modern MD there is 24 bit dynamic range carried through
the encode process by use of a bit shifting that's built into the spec
for MD. This is not the case in CD who's spec does not allow that. It's
not a important distinction due to the fact that nature recording so
rarely can produce a signal with a high enough dynamic range. And that
MD's output it as 16 bit to be consistent with CDs.

> I don't recommend this as a recording strategy though as this is quite
> laborious in practice. It would be straightforward I think to write an
> algorithm to do this, but by hand it's a drag -- so I actually usually
> just "eyeball" in the corrections by sketching a nicely rounded peak...

As one who has had to do the manual editing upon occasion to make a one
of a kind recording listenable, I agree, laborious is a understatement,
and I'm very capable with such graphic editing.

Another comment on that. Everyone should try it some. It will help to
teach you just how unimportant getting each bit exactly right is. It
generally only takes very crude editing to clean up these things.

> A final comment -- doing direct, unedited transfers to CD, I have noticed
> that some CDs players' D-A process "catch" this and correct it on playbac=
k
> themselve -- I imagine they do so as a last-ditch effort to compensate fo=
r
> a bad read. I've actually come close to sending out CDs that had this
> problem as result -- and learned to audition everything in the studio!

There is quite a bit of modification going on in the course of playing
digital recordings, particularly in consumer gear, but even pro gear can
be doing some. So much for the "digital is a perfect reproduction of the
original" idea.

Walt




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