Notes at the end of Gianni's valuable anti-aliasing compilation brought up =
a
long postponed task on which we would appreciate advice. There are many
hours of DAT tape of (largely downconverted) bat audio recorded either
manually or with a homebrew vox trigger for the D7 and D8; we need to
digitally transfe this material to another medium, both to make it more
accessible and preserve it against tape degradation.
Some is 48 kHz/16bit and the rest is Sony's 32 kHz 12 bit non-linear long=
play. We needed the long record times for all night runs and naively presu=
med
the 8-bit 20:1 downconversion of bat audio upstream of the DAT meant that=
the Sony digitization wasn't doing much more damage to the signal.
The vox trigger (largely a modified wired remote) tapes can have a hundred=
plus 30 second events sampled through a night, so in transferring them to
computer, the ideal system would involve software that reads the Sony
real-time subcode, creates a separate file with each start ID, and names th=
e
files with their start time.
Gallery Software (UK) once offered a Mac hardware software kit (DATstudio)=
that seemed as if it could do this, but we couldn't afford it. Several year=
s ago
I tried a similar approach with an audio capable SCSI DAT drive (one of the=
remaindered SGI units) coupled to a PC , and encountered reliability proble=
ms,
though it was unclear whether this was a software or hardware issue.
Now a large number of computer motherboards, add-on audio boards and
external USB or Firewire devices have SPDIF-in; some list a wide range of=
input sampling rates. When their specs mention 32 kHz, does this mean the=
Pansonic DAT type linear rather the Sony non-linear or both? I'm unclear
whether this is dependent on hardware, device firmware or audio capture
software. Is the 32 kHz four channel audio that is part of the miniDV stand=
ard
also 12 bit non-linear?
As Gianni and others have pointed out, digital inputs in some devices are,=
unfortunately, always resampled, so it seems reasonable to avoid those.
We have several generations of both Mac and PC computers around, so welcome=
recommendations even if they require nominally obsolete system software.
Thanks,
Bill R.
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