Description; System Features; Operating Principles - Shure SCM810 User Manual

The Shure Model SCM810/E is an eight-channel automatic mi-
crophone mixer designed for use in sound reinforcement, audio
recording, and broadcast applications. The SCM810 dramatical-
ly improves audio quality in any application where multiple micro-
phones are required. Any low-impedance dynamic or condenser
microphone (including wireless) can be used with the
SCM810/E. Multiple SCM810 mixers can be linked to other
SCM810/E mixers, as well as to Shure Models FP410, SCM410,
SCM800, and AMS8100 mixers.

SYSTEM FEATURES

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Fast-acting, noise-free microphone selection that automatical-
ly adjusts to changes in background room noise
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Automatic gain adjustment as additional microphones are acti-
vated
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Last Mic Lock-On circuit that maintains ambient sound
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Adjustable low-frequency rolloff and high-frequency shelving
for each channel
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Channel activation and clipping indicators

OPERATING PRINCIPLES

The operating concept behind the SCM810/E Automatic Mixer is

Shure's patented* IntelliMix
less automatic mixing by combining three separate functions:
•
Noise Adaptive Threshold. Distinguishes between constant
background noise (such as air conditioning) and changing sound
(such as speech) for each input channel. It continuously adjusts
the activation threshold so that only speech levels louder than the
background noise activate a channel.

DESCRIPTION

circuitry. IntelliMix delivers seam-
Each input channel has a two-band equalizer and three logic ter-
minals. The equalizer reduces unwanted low-frequency audio
pickup and makes different microphone types—lavaliers,
boundary and handheld—sound similar. The logic terminals can
be used to control external devices.
The SCM810/E operates on 100–120 Vac power; the SCM810E
operates on 220–240 Vac power. Each mixer is supplied with a
power cord, rack-mounting hardware, and a link cable.
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Peak-responding output limiter with selectable thresholds and
LED indicator
•
Active balanced microphone-level XLR inputs and an active
balanced Mic/Line level XLR output
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Aux-level input with manual level control
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Front-panel headphones output with level control
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Linking capability for up to 400 microphones
•
MaxBus. Controls the number of channels that may be acti-
vated for a single sound source. One talker activates only one
channel, even if multiple microphones "hear" that talker.
•
Last Mic Lock-On. Keeps the most recently activated micro-
phone open until another microphone is activated. Without
Last Mic Lock-On, a long pause in conversation would cause
all microphones to turn off, which would sound as if the audio
signal had been lost. Last Mic Lock-On ensures that back-
ground ambience is always present.
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