Theatre Design & Technology - Winter 1993 - 49

* auromaric level conrrol, and
* immediare manual override.
Inirially, a mororized fader seems ro elegandy provide borh fearures, bur rhis is nor
rhe case. If you wish ro override rhe programmed posirion, rhe moror musr be disabled so ir will nor "fighr" your hand or
make operarion difficulr. This means all
conrrol in rhis channel now resides wirh
vou, rhe operaror. To properly mix rhe
show, you must now remember all rhe programmed fader moves, and duplicare rhem
precisely while compensaring wirh live correcrions-a rail order ar besr. The problem
is compounded by rhe number of channels
needing correcrion. If you go back ro programmed conrrol you can no longer override or modifY rhe "canned" serrings.
This would all be easier if rhe conrrol
sysrem allowed serring an offser level above
or below rhe level inirially programmed. Ir
would also be useful ro vary rhe offser up
and down. In facr, if we simply pur a srandard, non-mororized audio fader beside
each moving fader and have rhe audio pass
rhrough borh, we meer rhese requiremenrs
wirhour a complex conrrol sysrem.
Now, wirh side-by-side faders borh
adjusring each channel's volume level, you
conrrol rhe srandard fader and rhe auromarion sysrem conrrols rhe moving fader. You
have no need ro rouch rhe moving fader
since ir is mororized and because any live
volume adjusrmenr can be easily obrained
wirh rhe regular fader. Manually adjusring
rhe moving fader may be useful in programming auromared moves, bur ir is in
facr rechnically easier ro use a regular fader
ro copy moves and rranspose rhem ro rhe
moving fader.
So now we have an environmenr meering all operarional needs, bur every audio
channel incorporares an expensive moving
fader which, oddly enough, you never need
ro rouch. \X/hy provide rhe second, moving
fader' Could we nor simply replace ir wirh a
variable gain elemenr such as a volrage conrrolled amplifier (VCA) or digirally conrrolled arrenuaror (DCA)' In facr, we could
simply inregrare an auromarion sysrem wirh
our exisring console since programming
does nor have ro be done by rhe console.
This configurarion has rhe added fearure of
remore or off-line programming, wirhom
necessarily requiring rime in rhe rhearre.
The auromarion sysrem conrrols rhe
variable gain elemenr, providing consisrenr
and reliable programmed volume level
changes, while rhe fader in each channel
allows you ro adjusr rhe same volume level
simulraneously. The ner volume level is rhe
combinarion of rhe serrings of rhe variable
gain elemenr and rhe fader. The nominal
fader posirion is "0 dB," represenring exacr-

Iy rhe same channel gain as when rhe show
was programmed.
You always know rhe volume is rhe same
as programmed whenever rhe fader is ar "0
dB." To compensare for a weak microphone, rhe fader can be easily increased as
required and rhe show will run normally
unril anorher adjusrmenr is needed. If rhe
microphone is repaired or replaced during
rhe show, simply reser rhe fader ro rhe nominal posirion. If an undersrudy sings differendy rhan rhe regular singer, you can conrinuously adjusr ro compensare for rhe
differenr sryles-all rhe rime knowing via
rhe fader posirion exacdy how far rhe level
is from normal.
This is far more logical rhan using
mororized faders. To rake over live conrrol
using moving faders, you musr disable rhe
auromarion and rhen arrempr ro simulare
all programmed moves along wirh all
desired changes. To pur rhe sysrem back
under auromared con[[ol, you musr
remarch levels perfectly wirh rhe programmed serrings and rhen enable rhe
auromarion. All in all, moving faders end
up looking much less arrracrive for live
sound rhan a programmable conrrol sysrem
properly inregrared wirh a regular console.

Programming Live Sound
Automation
Since auromarion for moving faders is
based on copying rhe operaror's morions, ir
could appear funcrionally superior for cerrain applicarions. Bur you musr always program rhese sysrems in real rime. For example, ir rakes ar leasr 90 seconds ro program a
90 counr fade. And ir would rake ar leasr a
minure ro SLIbsequenrly change ir ro 60
counrs-wirh many sysrems acrually
requiring you ro reprogram rhe full 90 seconds. A more rhearrical way ro program
rhese examples is ro firsr enrer "90" as rhe
fade rare, rhen larer change rhe figure ro
"60." This process rakes only a few seconds-helpful, since fades are frequenrly
changed before rhe righr values are found.
Recording engineers readily acknowledge ir rakes a long rime ro mix using a rypical auromared mixing sysrem. Piry rhe
poor sound designer who, afrer receiving
rhree pages of rech nores ar rhe end of a
long rehearsal, has ro rhen program new
levels and fades in real rime. Moreover, pir)'
rhe poor sound designer wirh a srudio-sryle
auromarion sysrem who is expecred ro
change a number of complex programmed
sound moves while rhe enrire casr and crew
wair around. People and equipmenr have
ofren been removed from producrions for
such cosdy delays.
Much as in lighring conrrol, whar marrers mosr are pracrical considerarions-pro-

gramming speed and efficiency. You don't
see lighring boards designed like auromared
mixing consoles.

Automated vs. Live
Timing and Fades
Srudio auromarion sysrems require SMPTE
rime code-a logical convenience since
every recording is a specific lengrh and
rem po. The srarr of rhe recording is given
an arbirrary "srarr rime" and rhe rime code
clock simply counrs up from rhere in fracrions of a second, or "frames." The rime
code clock is inirially recorded adjacenr ro
rhe sound e1emenrs onro a rime code rrack.
Thus, each sound elemenr in rhe recording
is always synchronized wirh an exacr
rime-or frame-whenever ir is played.
Auromarion is always referenced ro rime
code and an evenr's "Iocarion" is idenrified
by irs corresponding frame.
The serring of each fader or gain e1emenr
is defined by rhe sysrem, frame by frame.
The volume of each sound evenr in a
recording can rherefore be uniquely relared
ro each evenr's frame rime. Moreover, rime
code is predicrable, wirh irs frame rimes
ascending in order and ar a consranr rare.
This means rhe auromarion sysrem can
anricipare irs nexr moves-"knowing" rhey
should always happen exacrly as programmed.
Bur in rhe rhearre, rhe riming of each
scene, or even each line, can vary considerably from one performance ro rhe next. Ir's
always been hard ro ger acrors ro follow
SMPTE rime code. The mosr imporranr
job you have is ro make rhe sound follow
rhe show.
A rypical need is ro make programmed
fades happen ar rhe righr rime-and end ar
rhe righr rime. This involves relling rhe
auromarion sysrem ro begin and end fades
ar orner rhan programmed rimes. Ir rakes a
very special ki nd of auromarion sysrem ro
srarr a fade, rhen modify ir because of a
need ro change rhe fade rare-all rhe while
consrantly maintaining a conrinuous,
smoorhly changing audio level in all affecred channels.
Th is is a key d i fficu Iry encou n rered
when moving faders and srudio sryle
auromarion sysrems are adapred ro live
applicarions.
A sysrem locked ro rime code can nor
have rhese capabiliries. Even if ir could
respond ro varying or disconrinuous rime
code, ir cerrainly would nor have rhe inrelligence ro respond in a predicrably smoorh
and consisrenr manner.
Live performances are unpredicrable and
inconsisrenr, so a sysrem designed for live
conrrol has ro be more flexible and inrelligent. For example, if you make a cue which
TD&T

1993 WINTER

Table of Contents for the Digital Edition of Theatre Design & Technology - Winter 1993