[Table of Contents]


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [ARSCLIST] Space Shuttle Recorder - Link to NY Times article



At 06:06 PM 3/24/2003 -0800, Rod Stephens wrote:

The overall problem is a common one, I would guess, since many of the
machines used for archiving today are not in their first youths, and
wear of the various transport parts will cause changes in speed.  I
thought this should give others food for thought in checking out their
analog decks, and I hope my experience will be of help to others.

The irony here is that I'm sure the vendor from whom I purchased the
Scully wasn't aware of any problem, since he was doing "in house"
recordings, and, as long as the recordings were played back on the same
deck, they would be relatively "perfect", playing at the same speed they
were recorded.

I have gone back and remastered the offending recordings.  I have also
in some cases used my digital software to resample the .wav files using
the "time/pitch" tools in Cool Edit Pro, since I have now found that
some of the library's 1/4" tape masters were not recorded perfectly on
pitch, either, due to the machines they were using back in the '50's and
'60's.

So, the moral of the story is: "Nothing Is Perfect".

Not knowing the design of the deck, I cannot guess what part of speed regulation could have gone out to cause the problem. I want to note that correcting pitch in software is a compromise that I prefer to avoid. There is a simple alternative if you know the speed error when you begin and if the error is constant over the reel. In that case, simply adjust the sample rate.

On very rare occasion, I have a 78-rpm disc to digitize. To save space, I
long ago gave up my table and preamp for those, so if I know that the
recording is at 78 rpm, I simply record it with a suitable cartridge at 45
rpm and sample at 25442 sps - (45 x 44100) / 78. I use CDWAV for that
recording; most other programs restrict sample rates. I then change the
extension on the file so I can open it in CoolEdit as though recorded at
44100, clip off the header and correct the EQ.That is actually much simpler
than it sounds and avoids the delay and the imperfection of altering pitch
in the audio editor.


Mike mrichter@xxxxxxx http://www.mrichter.com/


[Subject index] [Index for current month] [Table of Contents]