Rane ECM 64 - Manual (Page 6)

Manual-6
Site Survey
Before you start any installation, be aware of these
quidelines. For the ECM 64 to operate properly the following
must be closely observed:
Ambient Noise Level - Air conditioning equipment (listen for
rushing air from registers and rattling air ducts), fan noise
from computer equipment, outside traffic noise, etc. Ideal is
NC 25 - NC 30 (35 to 40 dBA).
Room Absorption and Reverberation Time - For proper
operation, sound reflections must be held to a minimum. Use
sound absorption materials and non-parallel walls or geometri-
cal diffusers when possible. Ceilings should have an NRC
(Noise Reduction Coefficient) rating of .75 to .80 and walls
should have an NRC rating of .80 to .90.
Microphone and Loudspeaker placement - Boundary-type
microphones spaced 4 to 6 feet apart work best. These
microphones can reject about 12 dB of audio from the rear.
Never aim a microphone directly at any loudspeaker. Loud-
speakers are best placed at the front center of the room.
Ceiling speakers can be used if placed one foot or greater
behind the microphone, or four feet or greater in front of the
microphone. Angled ceiling speakers work best.
Make certain that there is adequate rack space - Keep all
ECS equipment in the same rack, along with plenty of ventila-
tion and power outlets.
Loudspeaker Audio Processing - If near-end speech is not
fed to the loudspeaker power amp, and any non-linear process-
ing is done (limiters, delays, etc.) between the ECM 64 and the
power amp, it is best to connect the same audio running to the
power amplifier also to the AEC REF IN on the ECM 64, and
in RaneWare set the
AEC REF to External In.
Ceiling Microphones - These microphones are not recom-
mended. If you must, the ceiling must be less than 10 feet in
height, and the room must have very low noise with a high NC
rating. Never place a microphone within 4 feet of an air
conditioning register. Using techniques such as out-of-phase
microphones or speakers may work in some rooms, but at best
you will only gain about 6 dB of speaker to microphone
cancellation.
Telephone Line - The telephone line should be a direct line to
the telephone company’s CO (Central Office). This line should
not be shared by others, as this may cause ground loops.
ECM 64 Connection
Overview
Balanced ‘Euroblock’ audio connections are used through-
out, except for the acoustic echo canceller connections.
To show the difference between hardware and software in
this manual, hardware connections will be serifed ALL
CAPITOLS LIKE THIS and named the same as the control or
connector on the ECM 64 front or rear panel. RaneWare
controls and commands will be in
Sans-serif type like this
and match the defaults shown in RaneWare. Be aware that
Inputs and Outputs may be given custom names in RaneWare
and may not match the text in this manual after they are
changed.
There are three methods to control the ECM 64: the front
panel, RS-232 (RW 232), or contact closure.
Front Panel
There are three front panel functions:
1. VOLUME UP & DOWN
2. OFF HOOK.
3. PORT STEP
VOLUME UP & DOWN changes OUT 1’s level. This may
be superceded with a room controller such as AMX or
Crestron.
OFF HOOK toggles between Off Hook (conference mode)
and On Hook when the DH 1 is installed. This may be
disabled by software. The OH indicator lights when Off Hook
is in conference mode.
PORT STEP selects the currently monitored input or
output of the level meter. See
ቮ on page Manual-2.
RS-232
RS-232 control is provided through the DB-9 female
INPUT connector. RW 232 uses the same protocol as RS-232.
Use a standard RS-232 cable to connect this RW 232 INPUT
to the RS-232 connector on a PC-compatible or control
system. If a Rane RW 232 device is already connected to the
PC or control system, use the supplied short DB-9 connector
to link the RW 232 OUTPUT of the upstream device to the
ECM 64 RW 232 INPUT. Check that the RW 232 devices are
set to different addresses (see RW 232 Communications
Interface on page Manual-24). Note: do not use a null-modem
cable for RS-232 control.
Memory Recall Port (MRP) / External Control
External contact closure control is provided through the
DB-15 female MRP/EXT. CTRL connector providing:
• Recall of internal Memories
• Level control for OUT 1 using external up / down buttons
• Control and status signals for Off Hook, Privacy and Mute.
Complete programmability of the MRP is possible using
RaneWare by selecting Device > Edit MRP Configuration.