| Tech Note | SFNR=Sonic Foundry Noise Reduction (narrow notch filter to remove whine
interference... see below)
Notes:
The short story:
1) I removed the whine (~8000 kHz tone at about +25 dB) from this show
that was present with the source reels using Sonic Foundry's Noise
Reduction algorithm, as I did with the earlier uploaded Port Chester
shows (2/18, 2/21, 2/24). For an explanation of the noise and how I
removed it, see http://www.mailbag.com/users/orf/notch.html
2) There are a couple of dropouts/glitches which I have
cleaned up as well as I can. These occurred when the DAT tape was
"ripped" to disk.
3) This show is as good as you're gonna get as far as I know because of
the NR and the excellent remastering from the original reels!
4) I've kept in all the intersong tuning/whatever. I figure others can
edit them down if the wish. I like having it there, sometimes funny
things are said and done :) plus you can always just hit FFWD on your CD
player remote to get to the next song!
The long story with regards to 2) above:
The DAT tape, a clone from the "whatever became of the bettys" tree a
while back, was borrowed and was read in on an old SGI indigo which has
firmware which can read DAT audio tapes and dump them to 48 kHz AIFF
files. Alas, I do not own a DAT machine and digital sound card, but I am
saving my money! Anyhow, the error correction on the SGI DAT drive was
pretty crappy, and there were a few dropouts/glitches on the read which
lasted anywhere from less than 1/75 s to a handful of seconds.
I have at my behest a professional quality DAT machine at a community
radio station I volunteer for (WORT) and brought my home tape deck in
which is a Harmon Kardon TD 4600, one of the earlier Dolby S decks (WORT
does not have a computer with a digital sound card). It is a very good
deck for analogue. The DAT deck at WORT was able to handle all of the
bad spots for this show that were not handled well by the SGI. I made a
dobly S copy of the bad spots, and pasted over (using an analogue AWE64
Soundblaster to go A->D) the glitches/droputs on the SGI read using
Sound Forge. The result is as good as i could do. Bear in mind that the
total amount I had to paste over represent a total of about 20 seconds
across the entire show, and I was able to 'fix' them completely. The
worst section was during Drums where there were a couple of sections
where up to on the order of 5-10 seconds wasn't read, and hence was
pasted over with the analogue copy. I leave it up to you to find them :)
Leigh Orf <orf@mailbag.com>
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