Shure SCM810 User manual

E2002, Shure Incorporated
TL1031(BH)
SCM810 STEREO MIXER
The Shure Model SCM810 is an automatic microphone
mixer using Shure’s patented IntelliMixoperational con-
cept. Intellimix activates only those microphones being ad-
dressed, minimizing the poor audio caused by multiple open
microphones. The SCM810 is an eight-channel mixer capa-
ble of being linked for installations as large as 400 input chan-
nels. The single-rack-height chassis is ideal for installations
with limited rack space. The removable header-type input
and output connectors are quick, convenient, and eliminate
the time and expense of wiring XLR microphone connectors.
SYSTEM FEATURES
SReliable, quick-acting, noise-free microphone selection
which automatically adjusts to changes in background
room noise
SUser-configurable parameters for automatic operation
SAutomatic gain adjustment as additional microphones
are activated (NOMA: Number of Open Microphones At-
tenuator)
SLast Mic Lock-On circuit maintains ambient sound
SAdjustable EQ per channel: low-frequency rolloff and
high-frequency shelving
S48 V phantom power selectable for each input
SActive balanced microphone- and line-level inputs and
line-level output
SHighly RF-resistant chassis and circuitry
SBi-color LED indication of channel activation and clipping
SLinking capability for systems up to 400 microphones
SNon-automatic aux-level inputs with level control
SFront-panel headphones output with level control
SPeak-responding output limiter with selectable thresh-
olds and LED indicator
SInternal modification permits 120 V operation (SCM810)
or 230 V operation (SCM810E)
SPECIFICATIONS
Measurement Conditions (unless otherwise specified):
Line voltage 120 Vac, 60 Hz (SCM810) or 230 Vac, 50 Hz
(SCM810E); full gain; 1 kHz, one channel activated; source
impedances: Mic 150 Ω, Line 150 Ω; terminations: Line 10
kΩ, Phones 300 Ω (tip-sleeve and ring-sleeve), Direct Out 10
kΩ; Auto mode, equalization controls adjusted for flat re-
sponse
Frequency Response (Ref 1 kHz, channel controls centered)
50 Hz to 20 kHz ±2 dB; -3 dB corner at 25 Hz
Voltage Gain (typical, controls full clockwise)
Output
Input Line Head-
phones Direct Out
Low-impedance
mic (150 Ω)80 dB 88 dB 34 dB
Line 40 dB 48 dB –6 dB
Aux 44 dB 52 dB —
Send/Return 20 dB 28 dB —
Inputs
Impedance
Input Designed for use with Actual
(typical) Input Clipping
Level
Mic 19-600 W10 kW-15 dBV
Line 32 kW10 kW+22 dBV
Aux 32 kW10 kW+22 dBV
Send/Re-
turn 32 kW10 kW+18 dBV
SCM 810 Automatic Microphone Mixer
Specification Sheet

Specification Sheet
SCM 810 AUTOMATIC MICROPHONE MIXER
2
Outputs
Impedance
Output Designed for use with Actual
(typical) Output Clipping
Level
Line >600 Ω60 Ω+18 dBV
Head-
phones 8-200 Ω, 60 Ωrecom-
mended
300 Ω+12 dBV
Direct Out >2 kΩ1 kΩ+18 dBV
Send/Return >2 kΩ1 kΩ+18 dBV
Total Harmonic Distortion
<0.1% at +18 dBV output level, 50 Hz to 20 kHz (through 20
Hz-20 kHz filter; Input 1 and Master at 5, all other controls full
counterclockwise)
Hum and Noise
Equivalent Input Noise -125 dBV. . . . . . . . . . . . . . . . . . . . . . . .
(150 Ωsource; through 400 Hz - 20 kHz filter)
Equivalent Input Hum and Noise -123 dBV. . . . . . . . . . . . . . . .
(150 Ωsource; through 20 Hz - 20 kHz filter)
Output Hum and Noise (through 20 Hz to 20 kHz filter; chan-
nel controls full counterclockwise)
Master full counterclockwise . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
-90 dBV
Master full clockwise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
-70 dBV
Common Mode Rejection
>70 dB at 1 kHz
Polarity
Mic/Line, Send inputs to all outputs are non-inverting; Aux
input to all outputs is inverting
Input Channel Activation
Attack Time 4 msec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hold Time 0.4 sec (switchable to 1.0 sec). . . . . . . . . . . . . . . . .
Decay Time 0.5 sec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Off-Attenuation
15 dB (switchable to ∞)
Overload and Shorting Protection
Shorting outputs, even for prolonged periods, causes no dam-
age. Microphone inputs are not damaged by signals up to 3
V; Line and Monitor inputs by signals up to 20 V
Equalization
Low-frequency 6 dB/octave cut, adjustable. . . . . . . . . . . . . . . .
corner from 25 to 320 Hz
High-frequency ±6 dB at 5 kHz, ±8 dB at. . . . . . . . . . . . . . . . . .
10 kHz, shelving
Limiter
Type Peak. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Threshold Switchable: off, +4, +8, +16. . . . . . . . . . . . . . . . . . .
(dBm at output)
Attack Time 2 msec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recovery Time 300 msec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Indicator Lights red when limiting occurs. . . . . . . . . . . . . . . . . .
Input LEDs
Green on channel activation, red at 6 dB below clipping
Phantom Power
46 Vdc open-circuit through 6.8 kΩseries resistance per DIN
45 596
Operating Voltage
SCM810: 120 Vac rated nominal (see Voltage Selection for
230 Vac operation), 50/60 Hz, 200 mA
SCM810E: 230 Vac rated nominal (see Voltage Selection for
120 Vac operation), 50/60 Hz, 200 mA
Temperature Range
Operating 0°to 60°C (32°to 140°F ). . . . . . . . . . . . . . . . . . .
Storage -30°to 70°C (-22°to 158°F). . . . . . . . . . . . . . . . . . . .
Overall Dimensions
44.5 mm H x 483 mm W x 317 mm D (13/4x 19 x 121/2in-
ches)
Net Weight
4.3 kg (9 lb 9 oz)
Certifications
SCM810: Listed by Underwriters Laboratories, Inc., listed as
Certified by Canadian Standards Association; SCM810E:
Conforms to European Union directives, eligible to bear CE
marking; VDE GS-Certified to EN 60 950; meets European
Union EMC Immunity Requirements (EN 50 082–1, 1992): RF
radiated (IEC 801–3): meets Criterion A, ESD: meets Criteri-
on B, EFT (IEC 801–4): meets Criterion B
REPLACEMENT PARTS
Knob, Master & Phones (white) 95A8238
Knob, Channel Gain (blue) 95B8238
Line (Power) Cord (SCM810) 95A8389
Line (Power) Cord (SCM810E) 95A8247
Link Cable 95A1143
APPLICATIONS
The SCM810 has numerous applications in sound rein-
forcement, audio recording, and broadcast. In any speech
pickup application where multiple microphones are required,
the SCM810 dramatically improves audio quality. Automatic
operation allows an individual talker’s voice to rise above
background noise and reverberation to become clearer and
more intelligible.
Each SCM810 handles up to eight microphone- or line-
level signals and two aux-level signals. Any high quality, low-
impedance, balanced dynamic or condenser microphone (in-
cluding wireless) can be used. Additional SCM810 mixers
(up to 50) can be interconnected using the rear-panel link
jacks. Non-automatic (manual) operation is also available.