Operation Manual

EF1210 U
SER
M
ANUAL
30 http://www.aspi.com Copyright © 1999, All Rights Reserved
phone toward the loudspeaker.
1.6. Adjust the loudspeaker volume so that a nominal dB SPL level based on Table 4
is registered at the microphone.
1.7. Use the L
EVEL
A
DJUST
buttons to adjust the channel input gain until 3 green and
1 yellow (or 0 dB) LED are lit on the I
NPUT
S
IGNAL
L
EVEL
M
ETER
.
1.8. Repeat steps 3 - 7 for all input channels.
1.9. Return all microphones to their normal operating location and orientation.
C
ALIBRATION
S
TEP
2: C
ALIBRATING
Z
ONE
O
UTPUTS
2.1. Once all input channels have been calibrated, press the A
UX
I
N
L
EVEL
/S
ETUP
button again to switch to Zone Output calibration. For Calibration Step 2, the
S
ETUP
LED will blink twice per period.
This step sets the nominal output level of the Zone Outputs to match your room
audio equipment. This step also lets you mark the maximum room loudspeaker
amplification level permissible without violating the room acoustic gain limit.
Note
.
It is vital to move the SPL meter and/or microphones so that each
microphone sees the correct dB SPL acoustic level as you are cal-
ibrating. Do not assume that because the first microphone sees
the dB SPL level, all other microphones will see the same level
(unless they are moved to occupy the same location as the first).
Note
.
Always double check the microphone level with normal speech
once the microphones are in normal operating position. Actual
speech levels may vary depending on room reverberation, etc.
Verify that you set a reasonable level (three green LEDs and one
solid yellow LED, or 0 dB) by actually talking and looking at the
meter.
Note
.
Use caution if the microphones lie in two acoustically separated
zones and you are only calibrating one zone. As you cycle through
microphones that lie in the other zone, no activity will be indicated
on the I
NPUT
S
IGNAL
L
EVEL
M
ETER
.