21 Jun
2005
21 Jun
'05
5:28 p.m.
On Mon, 20 Jun 2005 12:48:16 -0700 (PDT)
Vintage Computer Festival <vcf at siconic.com> wrote:
Cool Edit has the feature of allowing you to 'zoom in' all the way to
individual samples and 'rubber band edit' any individual sample you
want. I've used it to edit out 'pops' in LP recordings. You can just
grab the few offending samples in a 'pop' in the audio waveform and
smooth them down to the waveform they're interfering with. It's the
audio equivalent of a pixel-level bitmap editor. I have Total Recorder
too, but have always thought of it as much more limited.
On Sat, 18 Jun 2005, Scott Stevens wrote:
The 'fancy technology' I suggested was an oscilloscope. I don't see how
just using the cheapest garage sale tape player you can find is a better
technical approach than actually looking at the waveforms coming out of
the various cheap-garage-sale tape players you've rounded up. Looking
for clipping and comparing the pulsewidths of the signal on an accurate
time base should clear up a lot.
A somewhat 'crude' but simple thing you
can try is to listen to the
audiotape sound of the tape you created which you say was
successful. Then listen audibly to the tapes you're trying to
recover. If the pitch seems to match for the most part it isn't a
speed problem. If you have an oscilloscope, look at the amplitude
of the signal out of the cassette drive of the new 'working' tape
and compare to the one you're trying to recover.
As others have suggested, use the simplest tape player you can find.
Noise reduction circuits and other fancy technology will only cause
problems.
I haven't
done this, but there are decent tools nowadays for what
could be called 'high performance audio editing' that you can throw
at the problem, if you use your sound card to digitize the audio to
a WAV file.
I use Cool Edit 2000 (much less expensive than full-bore Cool Edit,
probably no longer available) for audio work. There are a LOT of
powerful tools for fiddling with audio now that we have all the
horsepower for DSP that a modern pee-cee provides.
I recommened Total Recorder. It's inexpensive and the folks that
develop it are very nice. They've allowed me to upgrade to new
versions without any additional fee, and they're very responsive
through e-mail. I registered it years ago to use for recording VCF
talks but never used it. I recently started using it to digitize audio
tapes and find it very nice to use.