QSC CM-16-A Owners manual

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CM16a

Amplifier Network Monitor
HARDWARE MANUAL

*TD-000086-00*

TD-000086-00 Rev.D

IMPORTANT SAFETY PRECAUTIONS & EXPLANATION OF SYMBOLS

The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the user to
the presence of uninsulated “dangerous” voltage within the product’s enclosure that may be of sufficient
magnitude to constitute a risk of electric shock to humans.

The exclamation point within an equilateral triangle is intended to alert the user to the presence of
important operating and maintenance (servicing) instructions in this manual.

SAFEGAURDS
Electrical energy can perform many useful functions. This unit has been engineered and manufactured to
assure your personal safety. Improper use can result in potential electrical shock or fire hazards. In order
not to defeat the safeguards, observe the following instructions for its installation, use and servicing.

CAUTION: To reduce the risk of electric shock, do not remove the cover. No user-serviceable parts inside.
Refer servicing to qualified service personnel.

WARNING: To prevent fire or electric shock, do not expose this equipment to rain or moisture.

1- Maximum operating ambient temperature is 50°C (122°F).

2- Never restrict airflow through the device fan or vents. Please insure that the air intake and

exhaust vents are unobstructed.

3- When installing equipment into rack, distribute the units evenly. Otherwise, hazardous conditions

could be created by an uneven weight distribution.

4- Connect the unit only to a properly rated supply circuit. The CM16a is suitable for connection to

100 - 240 VAC, 47 - 440 hertz, with no special considerations other than the appropriate IEC power
cord.

5- Reliable Earthing (Grounding) of rack-mounted equipment should be maintained.

FCC INTERFERENCE STATEMENT

NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to
Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a
commercial installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed
and used in accordance with the instructions, may cause harmful interference to radio communications. Operation of
this equipment in a residential area is likely to cause harmful interference, in which case the user will be required to
correct the interference at his or her own expense.

© Copyright 2004, 2007 QSC Audio Products, LLC QSC® is a registered trademark of QSC Audio Products, LLC “QSC” and the QSC logo are regis-

tered with the U.S. Patent and Trademark Office. All trademarks are the property of their respective owners.

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INTRODUCTION- OVERVIEW

The QSC CM16a Amplifier Network Monitor provides powerful amplifier management and zone paging capability in a QSControl networked audio
system using Ethernet networking technology to communicate with the host computer/system controller.

The host computer uses the QSControl application software to operate the networked audio system, including the CM16a’s and their amplifiers. The
software operates on the Microsoft Windows NT® version 4.0 operating system and can be customized using Microsoft® Visual Basic Professional
Edition.

This manual outlines the capabilities of the CM16a as well as its installation and connections. The operation of the CM16a is accomplished using
QSC’s QSControl software. Note that not all hardware features may be supported by the current software revision. Please refer to the software’s
documentation & help file for information regarding software features, usage and functions.

Each CM16a performs control and monitoring functions for up to 16 amplifier channels. This could be up to eight 2-channel or four 4-channel ampli­fiers (or some combination of these) at the time this document was printed. The amplifiers supported by the CM16a are the PowerLight, PL2, PL2A,
DCA, and CX series of QSC amplifiers that have a built-in DataPort. Models that do not have a built-in DataPort or models that have a DP-1 option or
“V2” DataPort (such as the EX, MXa, & ISA series) are NOT supported by the CM16a.

The DataPort connections are made with ordinary VGA computer monitor-type cables (HD-15 male-to-male). These cables are the same type that are
used on personal computer systems to connect the monitor to the computer. This allows you to use commonly available cabling for interconnecting
amplifiers to the CM16a. Each DataPort connection supports the control and monitoring functions for two audio channels. When using the CM16a
with amplifiers that have more than two channels (such as the 4 channel cinema amplifiers) additional DataPort connections are required.

The CM16a is a control and monitoring device that relies on software to do its job. The functions and capabilities provided in the design of the
CM16a can only be realized with proper software implementation. Keep in mind that this manual’s intent is to outline these capabilities and provide
a reference for properly installing and interconnecting the CM16a to the networked system’s host computer, the audio inputs and the amplifiers to be
controlled and monitored. A thorough knowledge of the control software’s features and operation will provide the best possible results for the end
user.

From all of us at QSC Audio Products, thank you for your purchase.

Note: PL2A amplifiers have programmable filters and crossovers. This makes gain “reporting” to the host unreliable as the
frequency content relates directly to reported output levels. Since the output level is used to calculate gain, it is not possible
to guarantee accurate gain reporting when the PL2A is set for any of its various frequency boost/cut/crossover modes.

WARNING

While QSC has endeavored to develop and produce the most dependable and robust ‘network’ audio product for your use,
due to the myriad of network situations and equipment that may be encountered in its implementation, QSC cannot be held
responsible for network conflicts and associated consequences that may result. For this reason, QSC strongly recommends
that the network used for implementation of QSControl products be completely separate from all other networks, data or oth­erwise. As such, should you elect to integrate QSControl products with your existing network system, all risks attendant to
such integration of QSControl products with your existing network or network systems are assumed by you. While QSC
strives to provide the highest quality technical solutions for networked audio products, in no event will QSC or its suppliers
be held liable for any damages, consequential, incidental or otherwise, including any claims for lost profits and/or savings
resulting from any attempted integration of QSControl products with your networking systems. No agent, employee or repre­sentative of QSC has any authority to alter or modify in any manner, the disclosures and recommendations set forth herein.

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PHYSICAL CHARACTERISTICS

•one rack space high (1RU) and has an

•internal, universal 100-240V AC power supply, 47-440 Hertz

•chassis depth is 37.7 cm (14.84”)

•chassis width, less rack ears, is 43.7 cm (17.20”)

•weight is approximately 5 kilograms (11 pounds)

FRONT PANEL

1- POWER switch
2- Cooling air exhaust vents (intake vents are located on left side of chassis as

viewed from the front)
3- POWER on indicator
4- DIAGNOSTIC indicator

REAR PANEL

1-DataPort connectors PORT A - PORT H
2-PORT A CH 1 - PORT H CH 16 three-pin receptacles for audio inputs
3-PAGE three-pin receptacle for paging audio signal input
4- MONITOR CHAIN, IN and OUT five-pin receptacle for audio monitoring func-

tions

5-RLY / TRG IN two-pin receptacle for remote sensing of switch closure or logic

event

5- RCV, XMT and LINK STATUS network status indicators
6- PORT A - PORT H connection indicators
7- Access hole for the BYPASS switch (this is not labelled on the panel)

6-RLY OUT three-pin receptacle for output terminals of CM16a’s internal SPDT

relay contacts
7-RCV, XMT and LINK STATUS network status indicators
8-10BASE-T RJ-45 Ethernet computer network connection
9-RS-232 port for network and firmware utilities
10-IEC-type detachable AC power cord receptacle (for connection to AC line

cord) with integral fuse holder

FUNCTIONS, BLOCK DIAGRAM & DETAILED DESCRIPTIONS

The CM16a performs remote control and monitoring of amplifiers. Below is a listing of the functions available for the supported QSC amplifiers. The following two pages
(Block Diagram part 1 & 2) illustrate the main functions of the CM16a. Following the diagram is a section giving detailed explanations on each functional block that will
aid in the use of the CM16a. Note that not all features may be supported by the current revision level of software (consult software documentation for supported feature
set). Where applicable, functions are available on each individual audio channel.

CONTROL FUNCTIONS

•Amplifier:Power (Standby/Operate Control)

•CM16a:Input Sensitivity SelectInput Source Select (Normal/Page)

•Signal Level ControlSignal Mute

•Signal Polarity SelectPaging Control (with customizable routing)

•Contact Closure Output (switching of internal relay for control of external device)

•Paralleling within DataPort Pair

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MONITOR FUNCTIONS

•Amplifier: Power StatusAmplifier Gain

•Amplifier ModelBridge Mode

•Load Monitor (impedance)Protection Status

•Output VoltageOutput Current

•Output Power (real)Heat Sink Temperature (with Over-Temp.)

•HeadroomClipping Detect

SPECIAL FEATURES

•DAC (digital-to-analog converter) that can be used for generating test signals

•RS-232 Port for setting of network address information and system diagnostics

•TFTP upgradeable firmware via Ethernet

BLOCK DIAGRAM, PART 1

•Output ShortOutput Open

•CM16aInput Level MeterOutput Level Meter

• Audio Monitor Module (4 channel mono. mixer)

• External Event Sensing (a logic-level or switch input)

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FUNCTIONS, BLOCK DIAGRAM & DETAILED DESCRIPTIONS (CONTINUED)

AUDIO FUNCTIONS

Audio Inputs- These are the 3-pin terminal block connectors used for balanced line level audio-signal input. This type of connector is sometimes called“Phoenix”or “Euro”

style.

Input Sensitivity- Sets the sensitivity of the Audio Inputs to either 1 Volt or 3 Volts (r.m.s.). This selection should coincide with the level of the audio signal provided for
each channel.

Input Source: Normal/Page- Selects the input source for each channel. Normal input is the audio connected at the Audio Input terminals. Page input is the audio pro­vided by the Paging Input Module.

Level Control- Provides adjustment of the signal level delivered to the amplifier for each channel. Adjustment is from -95.5dB to 0dB in 0.5 dB steps.

Meter-These points are indicators of where in the audio path the software can “meter” the audio.

Mute- Actively mutes the audio signal being passed by a channel. No signal is delivered to the amplifier when a channel is muted.

Parallel Mode- When parallel mode is selected, the input to the first channel is also applied to the second channel. When in parallel mode, the input is ALWAYS from the

first (or odd numbered) input. The second (or even numbered) input is ignored; this includes the PAGE signal. This feature is useful for sending one input signal to both ampli­fier channels without having to wire jumpers between the two input connectors. This mode is automatically enabled by the CM16a when the amplifier bridge mode is set to
any of the parallel modes available (see amplifier manual for details).

Polarity- Determines the polarity of the signal delivered to the amplifier for each channel.

BLOCK DIAGRAM, PART 2

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FUNCTIONS, BLOCK DIAGRAM & DETAILED DESCRIPTIONS (CONTINUED)

AUDIO MONITOR CHAIN FUNCTIONS

Pre-Fader Monitor- Monitors the audio path at the point before the Level Control block (i.e. the input to the CM16a).

Post-Fader Monitor- Monitors the audio path at the point after the Level Control, Mute, and Polarity blocks (i.e. the output from the CM16a).

Amplifier Monitor- Monitors the audio at the output of the amplifier (i.e. the speaker terminals of the amplifier).

Off- This selection disconnects the monitor for the channel.

Level Adjust- Provides adjustment of the signal level delivered to the Monitor Module from each of the selectable “tap” points of a channel’s audio

path. Adjustment is from -95.5dB to 0dB in 0.5 dB steps.

Monitor Module- This module functions as a four-input mixer with software selection of the input channels. The four selected channels are summed
with the external input, Monitor Chain In. For each of the inputs, the “tap” point is selectable from the pre-, post-, amplifier and off positions.

AMPLIFIER CONTROL FUNCTIONS

Standby/ Operate- Controls the amplifier’s power status-

ON- amplifier operational

STANDBY- amplifier in standby mode

NOTE! The amplifier must be powered in order to respond to any commands issued by the CM16a. This means the amp’s
power switch must physically be in the ON position.

AMPLIFIER MONITORING FUNCTIONS

Amplifier Model Detect- Identifies what model of QSC amplifier is connected to the CM16a’s DataPort.

Amplifier Gain Detect- Reports the setting of the amplifier’s gain setting (in dB) for each channel.

Bridge Mode Detect- Detects the position of the bridge mode switch on each amplifier.

Clip Detect- Detects amplifier clipping on each channel.

Headroom Metering- Reports the “available” remaining signal level that the input signal can be driven before clipping will occur.

Heat Sink Temperature Metering- Monitors the heatsink temperature of each channel of each amplifier connected to the CM16a. If the tempera-

ture exceeds a user specified value (in software) then the Over-Temp. “object” will alert the system operator.

Load Monitor Detect- Monitors the impedance of the load at the amplifier output for each channel.

Output Current Meter- Provides for metering of the amplifier’s output current on each channel.

Output Voltage Meter- Provides for metering of the amplifier’s output voltage on each channel.

Output Open Detect- Detects when the load connected to the amplifier is above a user specified value in software.

Output Short Detect- Detects when the amplifier load is below a user specified value in software.

Power Status Detect- Reports AC power status of the amplifier (ON/standby/ OFF).

Protect Status Detect- Reports if the amplifier has entered “protect” mode (such as thermal, over-current or power-up muting protect status).

Real Power Detect- Reports the “real” power the amplifier is delivering. This “real” power is not the same as “reactive” power. Real power is the

product of current and voltage times the cosine of the phase angle between them.

Threshold Adjust- This indicates that the behavior of the associated block requires the input of a threshold value in software that must be crossed
for the detection to occur. This allows the system operator to tailor the behavior of the system to each application.

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FUNCTIONS, BLOCK DIAGRAM & DETAILED DESCRIPTIONS (CONTINUED)

PAGING FUNCTIONS

Input Sensitivity- Sets the sensitivity of the Page Input to either 1 Vrms or 3 Vrms. This selection should coincide with the level of the audio signal

provided for the Page Input.

DAC- This is a digital-to-analog converter that takes digital information from the internal micro controller and outputs the corresponding analog “equiv­alent” to the appropriate channel PAGE insert points. This occurs only by instructions issued by the system operator or a custom control application.

Page Input- This is a 3-pin terminal block connector used for balanced line level page audio-signal input.

RS-232 PORT FUNCTIONS

RS-232 Port- The RS-232 (serial) port is used to communicate with the CM16a for Ethernet address set-up and other diagnostic purposes. Most users

will never have a need to access the RS232 port, but for customized networks and for troubleshooting system problems, it may be necessary.

For the RS-232 port utilities, see the Operation section, “Serial Port I/O Interface” which outlines the proper connection and communication settings
required to communicate with the CM16a via the serial (RS232) port.

If the CM16a is connected to an Ethernet network where the factory-provided IP address information is not acceptable, the IP configuration may be
changed using the RS-232 port. This involves connecting a computer with a properly configured serial port to the CM16a using a null-modem type cable
(such as a “Laplink” cable) and running a dumb-terminal program (HyperTerminal is the Microsoft® Windows- supplied program). DO NOT CHANGE
THE FACTORY SETTINGS UNLESS YOU ARE CERTAIN OF WHAT YOU ARE DOING! If addressing is configured incorrectly, the CM16a may not respond
to network control.

Note- The factory-programmed IP address is printed on a label affixed to the front panel of the CM16a. Record this IP address in a safe
place in case the label becomes lost.

CONTACT CLOSURE I/O FUNCTIONS

RLY OUT- This is a 3-pin terminal block connector used for remotely controlling an electrical device in an on/off manner (such as a cooling fan, an audi-

ble alarm, a light, etc.). An internal SPDT (single-pole, double throw) relay is controlled by software command. Its contacts are accessible at the rear
panel RLY OUT connector and are labelled:

NC (normally closed)
NO (normally open)
C (common)

RLY/TRG IN- Detects the closure (or opening) of a switch connected to the RLY/TRIG IN terminals on the rear panel. Also accepts CMOS and TTL

logic-level inputs. An example is the detection of a limit-switch that indicates an open door on an equipment cabinet.
This input may also be configured to activate (recall) certain presets without the need for a computer. Set-up for this feature is possible using the Serial
Port I/O or Telnet sessions outlined on pages 27 - 30 (ref. menu item #10).

NETWORK DESCRIPTION

QSC CM16a Amplifier Network Monitors are designed to operate on standard 10BASE-T Ethernet. Each CM16a operates as a respective node on its
network; each unit contains a programmable IP address in non volatile memory. To minimize network conflicts, each IP address should be unique. When
shipped from the factory, the CM16a’s factory-programmed IP address is printed on a label affixed to the front panel of the unit. Record the unit’s IP
address and serial number and keep in a safe place. Ethernet devices such as hubs, repeaters, switches and routers will usually afford the flexibility to
configure the network as needed.

The system controller computer on the network must have an Ethernet-compatible network interface card (NIC) installed. Additionally, if operation dur­ing power outage or interruption is required, an uninterruptible power supply (UPS) will be required for the host computer, CM16a, and any hubs,
switches or repeaters. If the CM16a is disconnected from the network for any reason, it will continue to process audio using the last settings, assuming
AC power is uninterrupted.

The CM16a connects to the network via its RJ-45 connector on the rear panel. This allows direct connection to a 10BASE-T network. Use Category 3 (or
better) unshielded twisted pair (UTP) Ethernet Cable. Most ready-made Ethernet patch cables available today are rated at least Category 5 making
them suitable for this application.

One side note regarding Ethernet cabling: Although Category 3 data cable is called out as the minimum requirement, it is increasingly difficult to find.
Higher grades of cable are becoming the “normal stock” with the proliferation of 100BASE-T Ethernet. Category 5 Ethernet cable is the most widely
available type of data cabling as of this writing. So what does this mean? Use Category 3 if it is available and cost effective. If the cost of Category 5
cable is not prohibitive, it may be desirable to do your cabling runs with Category 5 due to its increased data rate capabilities. The extra capability may
be needed for future system expansion where 100 BASE-T devices are used. 10BASE-T capability is all that is required for the CM16a and thus the call
out for Category 3 as the minimum.

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