Casella CEL CEL-414 User Manual
Page 51
AC (all except CEL-493/3):
Conditioned signal,
typically 7.75 V RMS
for FSD.
Recommended imped-
ance of any connected
device (including
interconnecting cable)
>10 kΩ and <50 pF.
Consult CEL about
cables for use with
equipment not
manufactured by CEL.
DC (CEL-493/3 only):
Logarithmic signal
48 mV/dB nominal, not
exceeding 5 V,
18 ms rise time and
0.5 ms decay time for
fast, slow and impulse,
rise and decay times
for peak signals
depend upon the
impedance of connec-
ted equipment.
Recommended
impedance of output
device >10 kΩ.d
DC (all except CEL-493/3):
Logarithmic signal
48 mV/dB nominal, not
exceeding 5 V,
125 ms rise time and
decay time for fast,
1 s rise time and decay
time for slow,
35 ms rise time for
impulse signals,
0.1 ms rise time for
peak signals,
Typically <50 ms
decay time for both
impulse and peak
signals,
Recommended
impedance of output
device >10 kΩ.
Analog inputs:
AC:
22.5 V
pk-pk
via
CEL-216 Line Input
Adaptors for Type 1
instruments (or
CEL-316 for Type 2),
Recommended
Table 5: Typical noise floor in pass bands CEL-266/3 [and CEL-328/2]
Centre
20 (Lo)
20 (Lo)
50 (med)
80 (Hi)
Freqency
A-weighted Linear
A + Lin
A + Lin
dB
dB
dB
dB
31.5
Hz
8 [5]
16 [8]
<39 [35]
<69 [65]
63.0
Hz
8 [5]
15 [10]
<39 [35]
<69 [65]
125.0
Hz
8 [5]
13 [12]
<39 [35]
<69 [65]
250.0
Hz
10 [7]
12 [13]
<39 [35]
<69 [65]
500.0
Hz
10 [11]
11 [14]
<39 [35]
<69 [65]
1.0
kHz
11 [14]
11 [14]
<39 [34]
<69 [64]
2.0
kHz
11 [16]
11 [16]
<39 [33]
<69 [63]
4.0
kHz
11 [17]
11 [17]
<39 [31]
<69 [61]
8.0
kHz
9 [16]
11 [18]
<39 [34]
<69 [64]
16.0
kHz
8 [13]
10 [19]
<39 [39]
<69 [69]
General CEL Sound Level Meters Handbook - Page 47