mapS giG: bad club acoustics + feedback eliminator = room sized instrument

[Simran gleason <simran.gleason@Sun.COM>]

Howdy loopers, srepool ydwoH!

Awhile ago I posted a gig spam about plans for using
a vocoder with tapping on a bad mic cable as the formant
in a dragon show in SF. Finally here's the report from 
that show:

I couldn't set up on stage, since the performance I was doing the music
for was there, and there weren't any other places in the sonic shadow
from the large club-sized sound system. So they put me underneath one of
the big sets of mains, right next to a wall of subwoofers. I'm thinking:
feebdack city. I was right. I asked 'em to cut out the subs for the
performance. The sound guy wasn't going to be there the whole night and
said the DJs would get pissed if we
turned off the subs. He had another idea:

he put a feedback eliminator in the chain, between my mixers and the
wall. We quieted the room, brought the mics up
one by one, and plugged our ears for the screeching. Actually there were
some pretty cool sounds that came out, in various frequency ranges
(biiig room!). The black box thought awhile, then all of a sudden:
silence. It had found the nasty resonant nodes in the room. There were
five frequencies (per channel) caught statically that way, and he
explained that there were five more that roamed the sonic spectrum,
looking for errant feedbackish signals, and summarily notched them. 

This is where things got fun. Since I like to search out resonant spaces
(caves, doorways, ceteras) to sing in, I tend to gravitate towards
singing into the resonant spaces in a system (be it electrical or
architectural). I found myself seeking out the resonant nodes that were
missed (so far) by the black box. The volume would swell, rise to a
crescendo, and then the black box would catch on to what I was doing and
squelch my frequency. After a bit I would find another. 

The end result was a slow sussuration of barely controllable frequency
swellings. The sound guy was horrified. I was having a fantastic time.
It really felt like I was playing the room.

In other news from the show, my "suite for vocoder and bad mic cable"
did not turn out, because the mic attached to the bad cable was picking
up way too much sound for the tapping on the cable to have any
differentiating effect. 

I did, however, use the "Alhambra Ghatam" to drive the 
vocoder. That mixed with a mic on the "Ghatam" sounded
great on the big club sound system, especially since
it hit one of the spaces lower resonant nodes. (The 
"alhambra ghatam" is a blue plastic 5 gallon water 
cooler jug). 

Simran


(I think the T shirt should have a picture of the dreaded againinator,
perhaps taken with a telephoto lens from across the parking lot?)