HK Audio CDR 210 F - Manual (Page 46)

Manual
COHEDRA
® & COHEDRA ® Compact
8 Operating the System
We recommend the following procedure to help
prevent errors and troubleshoot problems quickly.
The adverse effect of a mid/high cabinet dropping
out or an incorrect connection can seriously degrade
a line array’s performance!
8.1 Connecting Speaker Cords
Always ensure cables are laid out clearly and orderly!
You should be able to attribute enclosures to their
connected power amp channel and/or amp rack at
any time. This ensures flaws such as defective cords
can be pinpointed and repaired swiftly.
Example setup using a PB 5:
Channel 1 drives the array’s four (two or three) top
mid/high units, while channel 2 drives the four units
below that, and so forth. Thus, one HK AUDIO
®
LS cable can serve to drive a total of four mid/high
units per channel.
If more cabinets are connected, they are addressed
by an additional PB 5, and the channel 1-to-4
numbering system is repeated. See the chapter
on the PB 5 in the manual to learn more about
how to assign power amp channels to the PB 5’s
channels 1 to 4.
Take the same systematic approach when connecting
CDR 210 C subwoofers.
8.2 Activating Amp Racks
PR 8 and PR 16
Ensure the VX 2400s’ power switches are off and
the gain knobs are turned all the way down. Check
the Phase switches on the PB 5s or PB 2s. They
must all be set to +2 (or +3)! Once you have done
this, switch on the PS 32 circuit breakers on the
back of the amp racks. The DFCs and the PB 5 patch
bays are now supplied with power. First select the
appropriate filter for your setup on all DFCs (making
sure you select the same set on each!). If you are
unsure of how the amp rack or DFC was used in the
previous application (delays, EQ, etc. settings), as
a precaution carry out a hot reset on all DFCs and
then select the filter set on the DFCs! Read the
chapter on the DFC in the manual to learn more
about how to do this.
Before you can continue, you must first connect to
the amp racks the DFCs’ remote line and all of the
system’s audio cords.
8.3 Checking Individual Mid/
High Enclosures
The best method of checking cabinets is to play a
familiar song on a CD, routing the signal into the
mixer and out via the master channel. Set the master
level to a low-to-medium setting.
• Turn up channel 1’s gain knob. You will hear the
signal rendered by the array’s four top mid/high
cabinets. The display of the DFC assigned to this
pair should indicate incoming signal levels.
Important note: If you are located outside the high
frequency signal’s directivity radius, you will not
be able to hear this signal! This system check is
best performed with a helper positioned a suitable
distance from the array.
The rule of thumb is, if you can see the bottom
of the mid/high unit as a plane surface, you are
outside its directivity radius!
• Turn the channel 1 gain knob back down after
hearing the signal!
• Follow the same procedure for all other power
amp channels that you want to use. Be sure to
turn the gain knob down after each successful test!
Note: With this procedure, you are checking mid/high
cabinets in descending order; that is, from top to
bottom. A cabinet’s height affects its directivity, so
the lower the cabinets, the closer the listener should
move in towards the array.
• Follow the same procedure for the subwoofers.
• Once you have checked all cabinets successfully,
turn up all gain knobs, one after the other.
• Start with the channel 1 gain knob for the top mid/
high units, and then turn up the channel 2 gain
knob, and so forth. With every additional channel
that you activate, you should hear a boost in low
midrange response. If not, this may be due to a
phase inversion in the NF (or in extreme cases, in
the speaker cords)! Also check the PB 5’s or
PB 2’s Phase switch again.
• Proceed in the same manner for the subwoofer
channels.
8.4 Configuring the
Controller Network Using
Audio Controller Software
Once you have performed these tests, you can
configure the controller network. The type and size
of the configuration of course depends on the given
sound reinforcement task (PA left/right, center,
out-fills, etc.).
Read the chapter on DFC software in the manual to
learn more about networking controllers, creating
groups and setting delays and levels.