7
expandability
& chaining
-15dB, -10dB, and 0dB referenced to a 10Vpp
signal. Bear in mind that Eurorack electronic
circuits cannot handle voltages greater than
10V (20Vpp), therefore it is impossible to mix
four signals of 10Vpp without serious distor-
tion. It is recommended to keep your attenu-
ators between 50% and 80% of the full range
(unless your sources are very quiet).
The mixing bus in Ostrawa features a soft
clipping circuit that offers a gentle overdrive
for signals exceeding 16Vpp. This solution
prevents the harsh-sounding distortion re-
sulting from hard clipping should the sum of
your signals exceed the dynamic range of the
output stage.
EXPANDABILITY
Multiple Ostrawa and Praga units may be
chained to provide a cascaded sub-mix setup
such that the content of the mix bus of all up-
stream units is injected 1:1 into the mix bus
of every subsequent unit appearing at its sum
outputs (i.e., the output of each chained
module is added to the output of the following
module in the chain). The chaining headers
at the back of the module (fully compatible
between Ostrawa and Praga) should be con-
nected with the supplied ribbon cable so that
the out header of the preceding unit goes into
the in header of the following unit (fig. 6). The
in header of the first unit and the out header
of the last unit should remain unconnected.
Ostrawa features a special set of expander
ports allowing connection to a dedicated Bo-
humin expander. Please refer to the Bohumin
manual for its functions and installation in-
structions.
note:
Praga's Hrad expander is
not compatible with Ostrawa!
An additional pin header at the back of Ostra-
wa connects to a simple passive breakout pan-
el called Ustka (available separately) offering
individual VCA outputs that may be used for
multitrack recording.
ACCESSORY
Our Coal Mine black panels are available for
all Xaoc Devices modules. Sold separately. Ask
your favorite retailer. •
fig. 6: chaining multiple ostrawa and praga units
POWER
CONNECTOR
1967 VOLTAGE CONTROLLED MIXING SURFACE
REV
. 03.20
17
