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12
ENGLISH
SPECIFICATIONS
Measurement Conditions (unless otherwise specified): Line voltage 120 Vac, 60 Hz (SCM268) or 230 Vac, 50 Hz (SCM268E);
full gain; 1 kHz, one channel
activated;
source impedances: Mic 150
Ω
, Aux Level 150
Ω
; terminations: Line 600
Ω
, Mic 600
Ω,
Aux Out 10 k
Ω.
12 V phantom power off.
Frequency Response (Ref 1 kHz, controls centered)
Microphone Inputs: 150 Hz to 20 Khz
±
2 dB (built-in 80Hz
low-cut)
Auxiliary Inputs: 20 Hz to 20 kHz
±
2 dB
Low-Cut Filter (Microphone inputs only)
3dB down at 80 Hz, 6 dB/octave
Gain (typical, controls full clockwise)
Inputs
Outputs
Total Harmonic Distortion
<0.25% at +4 dBu output level (through 22 Hz—22 kHz filter;
Input 1 and Master centered, all other controls full counter-
clockwise)
Equivalent Input Hum and Noise(150
Ω
source; through 22
Hz—22 kHz filter)
124 dBV
Output Hum and Noise (through 22 Hz—22 kHz filter; chan-
nel controls full counterclockwise)
Master full counterclockwise: –92 dBV
Master full clockwise: –70 dBV
Common Mode Rejection
>80 dB at 1 kHz
Polarity
All inputs to all outputs are non-inverting
Overload and Shorting Protection
Shorting outputs, even for prolonged periods, causes no
damage. Microphone inputs are not damaged by signals up
to +10 dBV; Auxiliary inputs by signals up to +36 dBV
Phantom Power
12 Vdc open-circuit through 340
Ω
series resistance
Operating Voltage
SCM268: 100—120 Vac rated nominal, 50/60 Hz, 60 mA
SCM268E: 220—240 Vac rated nominal, 50/60 Hz, 30 mA
Temperature Range
Operating: –7
°
to 49
°
C (20
°
to 120
°
F)
Storage: –29
°
to 74
°
C (–20
°
to 165
°
F)
Overall Dimensions
44 mm H x 218 mm W x 162 mm D
(1.72 x 8.60 x 6.37 inches)
Net Weight
1.20 Kg (2 lbs, 10 oz)
Certifications
SCM268: UL & cUL Listed by Underwriters Laboratories, Inc.
SCM268E: Eligible to bear CE Marking. Conforms to Euro-
pean EMC Directive 89/336/EEC. Meets applicable tests and
performance criteria in European Standard EN55103 (1996)
parts 1 and 2, for residential (E1) and light industrial (E2) en-
vironments.
Replacement Parts
Knob, Master (blue) ............................................... 95B8752
Knob, Channel Gain (white)................................... 95A8752
Line (Power) Cords:
SCM268: 100-120 Vac (US/Canada)................ 95A8762
SCM268E: 220-240 Vac (EU) ........................... 95A8778
Fuse, SCM268 (5x20 mm,
250V, 80mA, slow-blow)........................................... 80A730
Fuse, SCM268E (5x20 mm,
250V, 40mA, slow-blow)............................................80J258
Hardware Kit ........................................................ 90AF8100
Link Bars (Bracket) ................................................ 53A8443
Single Mount Bracket............................................. 53A8484
Dual Mount Bracket ............................................... 53B8484
Optional Accessories
Line (Power) Cord, 230-240 Vac (UK) ................... 95A8713
Input
Output
Mic
Line
Aux Out
Low-impedance mic
(150
Ω
)
38 dB
76 dB
65 dB
Aux Level
3 dB
40 dB
29 dB
Input
Impedance
Designed for
use with
Actual
(typical)
Input
Clipping Level
Mic
19-600
Ω
1.2 k
Ω
–5 dBV
Aux Level
≤
2 k
Ω
21 k
Ω
>28 dBV
Output
Impedance
Designed for
use with
Actual
(typical)
Output
Clipping Level
Mic
low-Z inputs
0.2
Ω
–21 dBV
Line
>600
Ω
72
Ω
+18 dBV
Aux Out
>2 k
Ω
870
Ω
+7 dBV