User Guide

Model฀74/75฀User฀Guide฀ Issue฀3,฀November฀2016฀
Studio฀Technologies,฀Inc.฀ Page฀35
for Surround
to฀stereo฀or฀stereo฀signals฀converted฀to฀
mono.฀How฀these฀functions฀affect฀the฀audio฀
signals฀will฀greatly฀depend฀on฀how฀the฀
Model฀75฀is฀configured.฀Being฀aware฀of฀the฀
selected฀configuration฀will฀allow฀the฀func-
tions฀to฀serve฀a฀more฀useful฀role.
5.1฀to฀Stereo
The฀5.1฀to฀stereo฀downmix฀function฀allows฀
surround฀signals฀to฀be฀mixed฀or฀“folded฀
down”฀into฀a฀stereo฀(left฀and฀right)฀signal.฀
Phase฀relationships฀and฀inter-channel฀level฀
issues฀can฀be฀quickly฀observed.฀Please฀
refer฀to฀the฀Technical฀Notes฀section฀of฀this฀
guide฀for฀a฀detailed฀description฀of฀how฀the฀
5.1฀to฀stereo฀function฀mixes฀the฀surround฀
sources฀to฀stereo.
Using฀the฀5.1฀to฀stereo฀function฀simply฀฀
requires฀the฀button฀labeled฀Downmix฀฀
Stereo฀to฀be฀pressed.฀The฀button฀is฀always฀
set฀to฀“latch”฀the฀function฀on฀and฀off.฀The฀
associated฀LED฀lights฀when฀the฀function฀is฀
enabled.฀The฀stereo฀signal฀created฀by฀the฀
5.1฀to฀stereo฀downmix฀function฀is฀routed฀to฀
the฀left฀and฀right฀channels฀of฀the฀selected฀
monitor฀output.
Depending฀on฀how฀the฀Model฀75฀Control฀
Console฀is฀configured,฀the฀5.1฀to฀stereo฀
downmix฀function฀may฀automatically฀en-
able฀whenever฀the฀stereo฀to฀mono฀down-
mix฀function฀is฀enabled.฀This฀is฀provided฀
to฀ensure฀an฀operator฀hears฀a฀valid฀mono฀
signal฀when฀a฀surround฀source฀is฀selected฀
as฀an฀input.
Stereo฀to฀Mono
The฀operating฀characteristics฀of฀the฀stereo฀
to฀mono฀downmix฀function฀depend฀on฀the฀
Model฀75฀Control฀Console’s฀configuration.฀
Two฀stereo฀to฀mono฀downmix฀modes฀are฀
available,฀as฀are฀four฀attenuation฀levels.฀
In฀the฀mono-to-left-and-right฀mode฀the฀
function฀combines฀(sums)฀the฀signals฀on฀
the฀left฀and฀right฀channels฀and฀routes฀the฀
result฀to฀both฀the฀left฀and฀right฀channels฀฀
of฀the฀selected฀monitor฀output.฀This฀meth-
od฀is฀the฀same฀as฀found฀on฀many฀stereo-฀
oriented฀audio฀consoles.฀Useful฀for฀music฀
mixing,฀it’s฀not฀true฀monaural฀but฀rather฀
binaural.
The฀mono-to-center฀mode฀of฀the฀stereo฀to฀
mono฀downmix฀function฀combines฀(sums)฀
the฀left฀and฀right฀channels฀and฀routes฀the฀
result฀to฀the฀center฀channel฀of฀the฀selected฀
monitor฀output.฀This฀function฀allows฀a฀more฀
accurate฀reproduction฀of฀a฀mono฀signal,฀
but฀may฀not฀be฀suitable฀for฀all฀operators.
To฀enable฀the฀stereo฀to฀mono฀downmix฀
function฀simply฀requires฀the฀button฀labeled฀
Downmix฀Mono฀to฀be฀pressed.฀The฀button฀
is฀always฀set฀to฀“latch”฀the฀function฀on฀and฀
off.฀The฀associated฀LED฀will฀light฀whenever฀
the฀function฀is฀enabled.
Bandpass฀Filter฀for฀Mono-to-Center฀
Mode
A฀special฀feature฀has฀been฀included฀to฀as-
sist฀an฀operator฀in฀determining฀compatibil-
ity฀with฀“real-world”฀playback฀environments.฀
A฀bandpass฀filter฀can฀be฀inserted฀into฀the฀
path฀of฀the฀stereo฀to฀mono฀downmix฀sig-
nal฀when฀it฀is฀being฀routed฀to฀the฀center฀
channel.฀This฀allows฀the฀simulation฀of฀the฀
response฀of฀a฀loudspeaker฀associated฀with฀
an฀inexpensive฀monaural฀television฀or฀por-
table฀radio.฀The฀filter฀passes฀signals฀in฀the฀
range฀of฀100฀Hz฀to฀5฀kHz,฀while฀rejecting฀
those฀above฀and฀below.
To฀highlight฀for฀clarity,฀the฀bandpass฀filter฀
is฀only฀available฀for฀use฀when฀the฀stereo฀
to฀mono฀downmix฀function฀has฀been฀con-
figured฀for฀the฀mono-to-center฀mode.฀For฀a฀
detailed฀technical฀description฀of฀the฀band-
pass฀filter฀please฀refer฀to฀the฀Technical฀
Notes฀section฀of฀this฀guide.