This is retagged version of shnid: 98034

Grateful Dead
February 21, 1971
Capitol Theatre,
Port Chester, NY
gd71-02-21.sbd.orf.98034.sbeok.flac16

SBD -> Dobly A Reel -> Dolby A decode -> DAT -> Sound Forge NR -> CD-R

The Sound Forge noise reduction was used to attenuate a very narrow
frequency band (in the vicinity of 8000 Hz) which was present as
interference on the original reels. See my notes below for details.
_________________________________________________________________________

--Set 1--
101-d1t01 - Cold Rain & Snow (7:24)
102-d1t02 - Me & Bobby McGee (8:18)
103-d1t03 - Loser (7:37)
104-d1t04 - Easy Wind (9:21)
105-d1t05 - Playing in the Band (5:46)
106-d1t06 - Bertha (6:17)
107-d1t07 - Me & My Uncle (4:57)
108-d1t08 - Ripple (take 1) (1:31)
109-d1t09 - Ripple (7:53)
110-d1t10 - Next Time You See Me (5:41)
111-d1t11 - Sugar Magnolia (7:33)
112-d2t01 - Greatest Story Ever Told -> (4:43)
113-d2t02 - Johnny B. Goode (3:22)

--Set 2--
201-d2t03 - China Cat Sunflower -> I Know You Rider (11:36)
202-d2t04 - Bird Song (6:44)
203-d2t05 - Cumberland Blues (5:48)
204-d2t06 - I'm a King Bee (9:12)
205-d2t07 - Beat It on Down the Line (4:53)
206-d2t08 - Wharf Rat (11:02)
207-d3t01 - Truckin' (8:42)
208-d3t02 - Casey Jones (6:33)
209-d3t03 - Good Lovin' (16:55)
210-d3t04 - Uncle John's Band (7:36)
_________________________________________________________________________


The original reels of the Port Chester run of '71 were audibly
tainted due to a cable problem. The result is a tone which hovers
around 8000 Hz with an amplitude of about +20 dB above the noise
floor. This translate to a very annoying pitch, especially during quiet
sections, which is in the old-tv-tube or lousy-hard-disk or maybe even
the-sound-you-hear-after-you-slam-your-head-against-a-concrete-wall
class of 'whine'. Because this interference is 'monochromatic' it's
easy to get rid of if you have the processing power and a quick
FFT algorithm. I used the filter-shaping capabilities of the Sonic
Foundry Noise Reduction Plugin to tailor a very narrow notch filter
which attenuated the interference without affecting the rest of the
signal. And it's all done in the digital domain. Huzzah!

As a side note, I actually ended up crafting many filters to process
these shows. The frequency of the interference actually drifted anywhere
from 7700 to 8100 Hz during a given show. This was probalby due to a
slightly wandering reel speed. It made my work harder but when I tried
a much wider filter I started to be able to hear the attenuation in the
music. The filters generally go like this:

25 dB /- - - - - - - -\
/ \
/ \
0 dB | |
7830 7900 7970

The end result is no more annoying whine!

I also removed some of the nasty mic feedback in the 2/18/71 Bertha
using this type of filter.

Leigh Orf <orf@mailbag.com>
------------------------------------

Update (3/19/09): This is a re-seed. I have re-encoded the files
using FLAC, and added tags. For some more discussion about the notch
filtering, please see http://orf5.com/badnr.html
________________________________________________________________________

Tagging notes:
I altered the Orf tagging.
Show information is embedded within the header of each flac file.
It will display on any player capable of directly playing flac
files. If converted to wav during processing, all tags will be
stripped, however audio data will remain unaffected. If you must
transcode to a lossy format, do so directly Flac > Lossy.
Use ffp to validate audio integrity.
Md5 values will change if tagging is altered.
B. Proctor 6-08-09