Identifier9710994
Created AtTue May 23 2023 23:54:00 GMT+0000 (Coordinated Universal Time)
Media TypeWMA
Media Count3
NoteSBD -> Dolby 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.

* first performance

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

Trades Allowed
Performance
Grateful Dead 1971-02-18 Capitol Theater, Port Chester, NY
Set 1Bertha *
Truckin'
It Hurts Me Too
Loser *
Greatest Story Ever Told > *
Johnny B. Goode
Mama Tried
Hard To Handle
Dark Star >
Wharf Rat > *
Dark Star >
Me And My Uncle
Set 2Casey Jones
Playing In The Band *
Me And Bobby McGee
Candyman
Big Boss Man
Sugar Magnolia
Saint Stephen >
Not Fade Away >
Goin' Down The Road Feeling Bad >
Not Fade Away >
Uncle John's Band
Set 3

CommentMickey's last show until 1974-10-02
E.S.P. show
New Riders Of The Purple Sage opened.
Ned Lagin sits in on keyboards most of the show.
First time performed *

Jerry Garcia - Guitar
Bob Weir - Guitar
Ron "Pigpen" McKernan - Hammond B3, Harmonica
Phil Lesh - Bass
Bill Kreutzmann - Drums
Mickey Hart - Drums