auxiliary
send & return
6
gain approaches 0dB, the response is slightly
compressed to prevent an increase in loud-
ness (fig. 4).
AUXILIARY OUTPUTS
The stereo pair of aux send a outputs and
the pair of stereo aux return a inputs facil-
itate adding external effects in parallel to the
main mixing bus. A dedicated aux a knob in
each channel sets the amount of signal add-
ed to the aux bus.
There are two modes of the send function:
pre-VCA and post-VCA, similar to pre-fader and
post-fader sends in studio consoles. Pressing
the active|aux pre button for one second
toggles between them, which is confirmed by
changing the backlight color from green to yel-
low.
note:
pre-VCA mode (yellow backlight)
uses the original signal before attenuation
and panorama balance are applied. The pre-
VCA mode is the only way to obtain a fully wet
processed signal (with the channel's vol at-
tenuator turned all the way down).
Ostrawa does not offer control of the return
level. Therefore, you must take care of prop-
er external attenuation of your effect signal.
However, such a control is available in the
Bohumin expander, which also features a
second effects loop (aux b).
LEVEL INDICATORS
AND MIXING BUS LEVELS
Each of Ostrawa’s channels is equipped with
an individual post-fader level indicator. The
five LEDs show the state of a standard vol-
ume detector with thresholds at -40dB, -23dB,
1
2
3
4
fig. 5: ostrawa block diagram
main summing bus
aux summing bus
stereo
output
AUX
sends
AUX
return
chain output
chain input
vu
control
CV
volume
CV
balance
mute
input R
input L
pan
aux
vca
vol
vu
control
CV
volume
CV
balance
mute
input R
input L
pan
aux
vca
vol
