The Shure SCM820 is an 8-channel digital automatic mixer designed for use in speech applications, including sound reinforcement, broadcasting and audio recording. It dramatically improves audio quality in any application where multiple microphones are required. The mixer uses IntelliMix® technology to select channels to open to the mix bus, while attenuating other channels. The mixing mode is selectable to allow a range of automatic mixing styles.
Expanding upon Shure's classic SCM810 IntelliMix technology, the digital SCM820 delivers seamless automatic mixing by combining the following functions:
The mixer operates in one of five Mix Modes: Classic, Smooth, Extreme, Custom or Manual. The first three are factory settings that offer a range of reliable automixing styles. IntelliMix is configurable in Custom mode and turned off in Manual mode.
Classic
Classic mode emulates the default settings of the classic Shure SCM810 automixer. It is renowned for fast-acting, seamless channel gating and consistent perceived ambient sound levels.
Smooth
Smooth mode dynamically balances system gain between open and closed channels. The system gain remains consistent by distributing gain across channels to equal one open channel. This mode incorporates IntelliMix operating principles into a gain sharing mixing style.
Extreme
Extreme is an aggressive variation of Classic mode, configured to achieve maximum gain before feedback by completely attenuating closed channels.
Custom
Custom mode allows individual IntelliMix parameters to be fine-tuned and tailored from the GUI.
Manual
Manual mode deactivates IntelliMix to operate as a standard mixer. Channel and mix equalization, output limiter and mix bus routing are still active in this setting.
The SCM820 can operate as a single or dual mixer:
Single Mixer: Channels are routed to a single mix bus that sends the same audio to both Mix A and B outputs. This allows the same program to be sent to different rooms or recording applications. Output gain, parametric equalizer and limiter can be set separately for each mix.
Dual Mixer: Two separate buses provide independent automixes for each mix output. This allows two entirely different mixes to result from the same set of inputs. This is useful when the mixer is being used for two applications. For example, set Mix A to Classic mode for sound reinforcement, and set Mix B to Smooth for a broadcast feed. As a dual mixer, channels can be routed to Mix A, Mix B, Mix A and B, or neither mix bus.
The SCM820 features two channels of Digital Feedback Reducer (DFR). DFR uses Shure’s patented Adaptive Notch Filter algorithm to detect feedback and deploy up to 16 narrow-band notch filters, dramatically improving gain-before-feedback in a sound reinforcement system. DFR can be applied to any two channels of the SCM820, including the mix outputs.
Additionally, the mixer provides adjustable input equalization, limiting and a parametric output EQ to optimize the sound in any application.
The following table describes the four SCM820 model variations:
| Model | Description | |
|---|---|---|
| Connector Type | Network Card | |
| SCM820 | Block | Standard Ethernet |
| SCM820-DAN | Block | Dante Digital Audio |
| SCM820-DB25 | DB25 | Standard Ethernet |
| SCM820-DAN-DB25 | DB25 | Dante Digital Audio |
You can add digital networking capabilities to a standard SCM820 using the Dante Network Interface Card (A820-NIC-DAN). The card replaces the standard Ethernet port with 2 Dante network ports. This upgrade should only be installed by qualified service personnel.
Update the firmware on the SCM820 before installing the Dante Network Interface Card. Visit www.shure.com for more details.
① Channel Mode Selection
Press the button to select the function of the channel knobs and monitor LED rings. See the Audio Signal Adjustment section for details on each mode.
② Assignable Channel Knob
Adjusts settings and status for each input:
Rotate: Adjusts a setting.
Momentary Press: Solos the channel to the headphone output.
Press and Hold: Mutes the audio or bypasses the EQ setting.
③ Monitor LED Ring
13 LED segments display gain setting, input signal meter, IntelliMix gain meter, channel solo, or EQ setting.
④ Channel Status LED
| LED | Channel Status |
|---|---|
| Off | Channel is closed (attenuated in the automix). |
| Green | Channel is open (selected in the automix). |
| Amber | Channel EQ is bypassed. |
| Flicker Red | Signal is clipping. Set the channel to a lower input gain level. |
| Solid Red | Channel is muted. |
⑤ Auxiliary Input Jack (1/8")
Unbalanced aux input sums left and right channels to mono. Front and back panel aux inputs are summed to a mono signal and routed without automixing to the mix outputs.
⑥ Master Output Knob
Adjusts settings and status of the mix outputs. See Front Panel Modes for details.
Rotate: Adjusts output gain or limiter threshold.
Momentary Press: Overrides a soloed channel to return the mix to the headphone output.
Press and Hold: Mutes the audio or bypasses the limiter.
⑦ Master LED Ring
Displays gain setting or limiter threshold. A single LED represents each mixer when they are both selected but set to different levels.
⑧ Master Mode Selection
Selects the function (gain or limiter) of the master knob and LED ring.
⑨ Mix Select Button
Selects Mix A, Mix B, or both for adjustment with the master knob and monitoring on the LED ring and headphone output. Note: When both Mix A and Mix B are selected, the headphone output only monitors Mix A.
⑩ Mix Status Indicator
| LED | Mix Status |
|---|---|
| Green | Mix is selected for adjustment and listening on the headphone output. |
| Amber | Limiter is bypassed. |
| Red | Mix is muted. |
⑪ Audio Output Meters
Monitor the output signal level and limiter threshold for mix A and B.
⑫ LIM (Limiter) LEDs
Illuminate amber when the audio levels exceed the limiter threshold.
⑬ System Status Indicators
The LEDs illuminate to indicate system settings:
| LED | Color | Status |
|---|---|---|
| power | Green | Unit is powered on. |
| ethernet | Green | Unit is connected to a network. |
| network audio | Green | All connected receive channels are OK (receiving digital audio as expected). |
| Flashing Green | One or more connected receive channels experiencing a subscription error or is unresolved (transmitting device is off, disconnected, renamed or has incorrect network setting). | |
| Red | Clock synchronization problem. | |
| Off | No receive channels connected (routing has not been established). | |
| automix link | Green | Two or more mixers are connected in a link group. |
| Flashing Green | Link Group is configuring. | |
| Off | Mixer is in standalone mode. | |
| dual mixer | Green | Mixer is set to Dual Mixer operation. |
| Off | Mixer is set to Single Mixer operation. | |
| lockout | Red | Front panel controls are locked. |
| Flashing Red | An adjustment is attempted in lockout mode. |
⑭ Headphone Volume Knob
Adjust the volume of the headphone output.
⑮ Headphone Output Jack (1/4 in.)
Monitor a mix or a soloed channel.
① Power Switch
Turns the unit on or off.
② AC Power Jack
Supplies AC power to the mixer when plugged into a power source.
③ Mix A and Mix B Outputs
Active balanced outputs connect to amplifiers, DSP, mixer, or recording device.
④ Auxiliary Input Jack
Unbalanced aux input sums left and right channels to mono. Front and back panel aux inputs are summed to a mono signal and routed without automixing to the mix outputs.
⑤ Channel Inputs 1–8
Active-balanced microphone- or line-level inputs.
Block Connectors
Audio +
Audio −
Audio ground
gate
Logic gate out
mute
Logic mute in
ovrd
Logic override in
gnd
Logic ground
DB25 Connector
Pins
Audio plus, audio negative and audio ground. See Specifications for details.
⑥ Direct Outputs 1–8
Each channel has a dedicated, impedance-balanced direct output on the back panel that can be selected from one of five stages in the signal path. See Configuring the Inputs and Outputs for details on direct output routing.
⑦ Chassis Ground Screw 1–8
Provides an optional connection for microphone shield wire to chassis ground.
⑧ IntelliMix Select Buttons
Scrolls through IntelliMix presets for each mix output. When dual mixer is off, the A button sets the mode for both Mix A and Mix B.
⑨ Dual Mixer Button
Sets the SCM820 as a dual mixer, indicated by the green LED.
⑩ Channel Select Button and Display
Press to select a single channel (1–8) or all channels (A) when changing input gain or phantom power.
⑪ Input Gain Selection and LED Indicator
Sets the analog input gain level for the selected channel(s), illuminating the green LED. All LEDs are off when the channel's audio source is set to Network from the GUI.
⑫ Phantom Power Button and LED Indicator
Supplies 48 VDC phantom power to the selected channel(s), illuminating the green LED. Phantom Power is disabled in the line (+0dB) gain setting.
⑬ Auto Link Button and LED Indicator
Enables networked SCM820-DAN mixers to automatically form a link group. Link Groups enable a larger audio mix by incorporating inputs from two or more mixers. See Link Groups for more details.
⑭ Lockout Button and LED Indicator
Hold for five seconds to disable front and back panel controls. The front panel lockout LED illuminates red (flashing red during an adjustment attempt) and the back panel channel display shows L.
⑮ Reset Button
Press and hold for five seconds to reboot the mixer with default system settings restored.
⑯ Network Ports
RJ-45 jacks for network connection.
⑰ Network Status LED (Green)
Off = no network link
On = network link established
Flashing = network link active
⑱ Network Speed LED (Amber)
SCM820:
Off = 10 Mbps
On = 100 Mbps
SCM820-DAN:
Off = 10/100 Mbps
On = 1 Gbps
The following diagram shows the audio signal path and the routing options for several features (default configuration shown). Use the web application to change the configuration.
Audio Source Selection
Input Meter Mode
Headphone Mode (Channel)
Mute Control
Direct Output Selection
The channel knobs operate in five modes for different types of input signal adjustment and display. Use the front panel mode selection button to select from the following modes.
Channel Gain (gain) 
|
Adjust gain within a 128 dB range while displaying the gain setting on the LED ring. Unity gain is at the 9th LED. |
Low Cut (low cut) 
|
Adjust the frequency of the low cut filter (6 dB/octave from 25 to 320 Hz). Use to remove low-frequency noise such as table vibrations or air-conditioning rumble. |
High Shelf (hi shelf) 
|
Adjust the high shelf boost or cut (± 12 dB at 5 kHz). Use to add presence to muddy vocals, temper sibilant vocals, or enhance the sound of off-axis lavalier microphones. |
Input Signal Meter (ch. meter) 
|
LEDs display the input signal level in real-time. Channel gain is adjustable in this mode, and will momentarily display channel gain setting during adjustments. |
IntelliMix Gain Meter (gain and ch. meter)
|
LEDs display the IntelliMix attenuation applied in realtime. Channel gain is adjustable in this mode, displaying the setting on the LEDs during adjustments. |
The mix output knob operates in two modes to control the mix output. Use the master function button to select one of two modes.
Output Gain (gain) 
|
Rotate to adjust the output gain of the selected mix. The output signal level is displayed on the meters. |
Limiter Threshold (limiter) 
|
Rotate to adjust the limiter threshold of the mix (−2 to −50 dBFS). The limiter threshold level is displayed on the meters. |
Mode Selector
Mute Channel Input
Press and hold the input channel knob while in gain or ch. meter mode. The channel status LED turns red.
Mute Mix Output
Press and hold the MASTER knob while in gain mode. The mix status LED turns red.
Bypass Input EQ
Press and hold the input channel knob while in low cut or hi shelf mode. The channel status LED turns amber.
Bypass Output Limiter
Press and hold the MASTER knob while in limiter mode. The mix status LED turns amber.
Use the front panel headphone jack for monitoring audio. By default, the headphones monitor the mix pre-fader/post-EQ (change to post-fader/post-limiter from GUI > Preferences Tab).
Solo to Headphones
A channel can be soloed to the headphone jack.
Solo Channel
Press a channel knob to solo that channel to the headphones. The other LED rings dim to highlight the soloed channel.
Exit Solo
Press the soloed channel knob or press the Master knob to return the mix to the headphones.
The front panel channel meters can be set to display real-time signal information. Use the front panel mode selection button to scroll to the desired mode:
Input Signal Level
The channel meter mode (ch. meter) displays real-time audio input signal level for each channel.
IntelliMix Gain
The IntelliMix meter mode (gain and ch. meter illuminated) displays IntelliMix gain operation in real-time across the channel LEDs. Channels that gate open will display more gain than channels that are closed (attenuated) in the mix.
The output meters indicate the level of each mix before the digital-to-analog conversion. By default, the meter displays average and peak audio levels. It is good practice to use −18 dBFS on the SCM820 meter as an approximation of 0 VU on an analog meter.
| LED | Description | Signal Level (dBFS) |
|---|---|---|
| Red (7) | Clip | 0 to -6 |
| Yellow (6) | Normal peaks | -6 to -9 |
| Yellow (5) | -9 to -18 | |
| Green (4) | Signal Present | -18 to -24 |
| Green (3) | -24 to -36 | |
| Green (2) | -36 to -48 | |
| Green (1) | -48 to -60 |
Go to the Preferences tab of the GUI to change the following metering options:
The SCM820 application enables comprehensive control of the mixer. The application is accessible from any computer. Use the application for the following functions:
Operate the control software on computers and mobile devices that meet the following criteria:
Follow these steps to install the software and access the SCM820 app:
① Get the Shure SCM820 application and the Shure Microflex Wireless (MXW) application
Get these applications to see devices on the network and open the control interface. Download the software from www.shure.com/software.
② Connect the network
Ensure that the computer and the mixer are on the same network.
③ Launch the Microflex Wireless (MXW) application
The application displays all Shure devices on the network.
④ Access the SCM820 application
⑤ The SCM820 application opens
| Use MXW application to specify network type | Network type
|
| Use Dante Controller to change |
|
Connect the unit to AC power using the supplied IEC cable. Turn on the power switch.
Rackmount the mixer using the screws and washers supplied in the Hardware Kit. Follow these general best practices when rackmounting equipment:
① Channel Inputs
② Aux Inputs
Aux-level sound sources:
③ Mix Outputs
④ Direct Outputs
Unless where noted, configurations can be made from the hardware or from the GUI.
| ① Select the Audio Source (GUI only) |
|
| ② Select the Input Gain | Select the analog input gain for each channel. No gain is applied for analog line-level or when the audio source is set to Network.
|
| ③ Supply Phantom Power | Supply 48 V phantom power to the channel when using condenser microphones. (Phantom power is disabled when Input gain is set to Line.) |
| ④ Adjust Channel EQ | Adjust the high- and low-frequency equalization to improve intelligibility and reduce undesired noise:
|
Channel Selection
To adjust the Input Gain or Phantom Power, press the CH to scroll to A for All channels, or select a single channel.
Channel Mode Selector
Select a mode to adjust gain or EQ settings.
Mix Mode Selector
Select a mode to adjust output level or limiter threshold.
Input Tab
Output Tab
⑤ Assign the Direct Outputs (GUI Only)
Assign the Direct Output for each channel from the Output tab of the GUI.
⑥ Set Mix Output Level (GUI Only)
Set the Output level according to the input of the connecting equipment:
⑦ Set the Limiter
The output limiter prevents distortion during loud program peaks without affecting normal program levels. This prevents overloading the devices connected to the mixer outputs.
⑧ Adjust the Output Gain
Adjust the overall output level of the mix.
The SCM820 features two auxiliary inputs: an 1/8” jack on the front panel and a back panel input (block connector or RCA connectors, depending on the model). Each input sums the left and right channel to a mono signal. This mono signal is routed directly to the mix outputs, bypassing the automixing process. Use this input for sources such as an MP3 player or computer speaker output.
When the mixer is connected to a Dante network, the left and right channels are accessible before they sum to the mono signal for the mix outputs. Use the Aux L and Aux R channels in Dante Controller to route audio to and from the aux channel.
The SCM820 uses IntelliMix to select channels to open in a mix, while attenuating the gain of closed channels. IntelliMix is available in three presets to excel in any application where multiple microphones are used at once. In all modes (except Manual), MaxBus ensures that only one channel is opened per sound source.
The SCM820 features five mix modes: Classic (Default), Extreme, Smooth, Custom or Manual.
Classic mode emulates the classic Shure SCM810 automixer (in its default settings). It is renowned for fast-acting, seamless channel gating and consistent perceived ambient sound levels. The Classic mode excels in most applications, specifically sound reinforcement and teleconferencing.
| Gating Style: | Full |
| Gain Scaling: | Fixed |
| Off Attenuation: | −15 dB |
| Last Mic Lock On: | Enabled |
| Hold Time: | 400 ms |
| NOMA: | 3 |
| NOM Max: | 8 |
Channel Gain in Classic Mixer
1 Talker
Full gain is applied as the channel opens; off attenuation gain is applied to all channels.
2+ Talkers
As additional channels open, NOMA factor decreases the level of all channels.
Smooth dynamically balances system gain between open and closed channels. The system gain remains consistent by distributing gain across channels to equal one open channel. It incorporates IntelliMix operating principles into a gain sharing mixing style, making it ideal for broadcast and recording applications.
| Gating Style: | Relative |
| Gain Scaling: | Adaptive |
| Off Attenuation: | Disabled |
| Last Mic Lock On: | Disabled |
Tip: Unroute all unused channels to the mix bus. This will ensure the most consistent noise floor in Smooth mode.
Channel Gain in Smooth Mixer
1 Talker
Relative gain is applied to the open channel; all channels adaptively attenuate to maintain system gain.
2+ Talkers
As additional channels open, gain is adaptively distributed across all channels to maintain system gain.
Extreme is an aggressive variation of the Classic mode, configured to achieve maximum gain before feedback by completely attenuating closed channels. Only open channels add to the system levels and ambient sound. Extreme mode is designed for sound reinforcement applications.
| Gating Style: | Full |
| Gain Scaling: | Fixed |
| Off Attenuation: | −110 dB |
| Last Mic Lock On: | Disabled |
| Hold Time: | 400 ms |
| NOMA: | 3 |
| NOM Max: | 8 |
Channel Gain in Extreme Mixer
1 Talker
Full gain is applied to the open channel. Closed channels are fully attenuated.
2+ Talkers
As additional channels open, NOMA factor decreases the level of all channels.
Manual mode deactivates IntelliMix to allow the SCM820 to operate as a standard mixer. All Channel Status LEDs remain on in this mode to indicate there is no IntelliMix attenuation. Channel and mix equalization, output limiter and mix bus routing are still active in this setting.
Tip: Be careful when switching to Manual mode, as all microphones will gate open to full gain, which may result in feedback.
Custom mode allows IntelliMix parameters to be fine-tuned and tailored from the web application. The mixer automatically switches to Custom once a parameter is changed in Classic, Extreme or Smooth mode. Theses configurations are saved to the device and will persist after the mixer is turned off and restarted.
Gating Style
Determines the way gain is applied to open channels.
| Full | Channels open at full gain (as adjusted by the NOMA factor). |
| Relative | Channels open at a gain level that varies with the input signal level—quieter signals receive less gain than loud signals. As the input signal level increases, more gain is applied to the channel. |
Gain Scaling
Determines off attenuation and its effect on the total system gain.
| Fixed | Off attenuation is a fixed amount. Total system gain varies with the number of open channels. |
| Adaptive | Off attenuation is adjusted to maintain a uniform system gain comparable to that of a single open channel. |
| Off Attenuation: -15 dB | The amount of attenuation applied to closed channels. |
Last Mic Lock On
Avoids ambient dropout by keeping at least one channel open at all times. The last channel opened remains open until another takes its place. (Fixed value based on mixer mode.)
Hold Time
Determines the minimum amount of time that a channel is gated open. (Fixed value = 400 ms)
Number of Open Microphones Attenuation (NOMA)
System gain is attenuated as additional channels are opened in a mix. This is configured per doubling of open channels, adjustable from 1– 6 dB for each mix that has Gain Scaling set to Fixed. (Fixed value = 3)
Maximum Number of Open Microphones (Max NOM)
Identifies the number of microphones that can be open at a time in a mix. (Fixed value = 8).
Note: If you had a previous version of the SCM820 firmware and made changes to these default settings, your specified settings are retained. Resetting to factory defaults will use the factory defaults permanently for those settings that have fixed values.
Press the Mix A or Mix B button on the mixer back panel to scroll through the five modes. From the IntelliMix tab of the application, you can select a preset or configure the IntelliMix as a Custom setting.
Mixes A and B have the same IntelliMix settings when the SCM820 is to Single Mixer Operation (default).
The mixer can be set to perform one or two automixes:
Enable dual mixer operation by pressing the Dual Mixer button on the back panel or from the IntelliMix tab in the SCM820 application.
Back Panel
SCM820 application
Connect the mixer to a network for hardware control from a Windows computer, transporting digital audio, or using multiple mixers.
For most installations, the SCM820 can connect to a computer either directly or though a network switch ("Link-Local" connections). Connect multiple mixers to a switch in a star configuration to ensure reliable networking (each unit connects directly to the switch).
In some cases, computer settings or programs may interfere with the network. The majority of these connection issues can be solved by using a DHCP-enabled router*. Most routers include a DHCP server, while switches do not.
*Note: DHCP servers are not recommended for redundant network configurations. See Redundant Network Recommendations for more details.
To network SCM820 mixers, ensure the setup meets the following requirements:
Multiple Mixers
Connect multiple mixers together in a star configuration using a DHCP-enabled router for the most reliable network setup.
Single Mixer
The SCM820 can connect directly to a computer. (This setup may take a minute or longer to establish a connection between devices.)
Dante® digital audio is carried over standard Ethernet and operates using standard internet protocols. Dante provides low latency, tight clock synchronization, and high Quality-of-Service (QoS) to provide reliable audio transport to a variety of Dante devices. Dante audio can coexist safely on the same network as IT and control data, or can be configured to use a dedicated network.
The SCM820 transports two types of data over the network: Shure Control and Dante Audio and Controller. They are transported to/from the two network ports depending on the mixer's network settings.
Shure Control
The Shure Control carries data for the SCM820 application, firmware updates and 3rd party control systems (AMX, Crestron). This network is supported by all SCM820 models.
Dante Audio and Controller
The Dante network carries both the digital audio and the control data for Dante Controller. This network is supported by Dante-enabled SCM820s.
In addition to the basic networking requirements, Dante audio networks should use a Gigabit network switch or router with the following features:
The Dante network card is a two-port interface that can be configured to enable the following applications:
The Dante network interface can be configured to operate in one of three modes: Switched, Redundant Audio, or Split. This setting determines the types of data that are transported from the Primary and Secondary ports.
The following table displays the configuration of the Dante network ports in each Network Mode.
Note: Always connect the Primary port to the network that is used for Shure Control.
| Network Mode | Port Function | Application | |
|---|---|---|---|
| Secondary | Primary | ||
| Switched (default) |
Shure Control Dante Audio and Controller |
Shure Control Dante Audio and Controller |
Typical installations of star or daisy-chained networks. |
| Redundant Audio |
Dante Redundant Audio |
Shure Control Dante Audio and Controller |
Create a backup audio network. |
| Split |
Dante Audio and Controller |
Shure Control | Isolate Dante and Shure Control networks |
Caution: Disconnect the equipment from the network prior to changing the network mode. This will avoid a network loop that will make the network unstable.
Warning: Do not reconnect mixers to the network until the network configuration is the same for all units.
| Star Configuration (Recommended) | Connect multiple mixers to a router in a star configuration for the most reliable setup. |
| Daisy-Chain (up to 4) | Up to four SCM820-DAN mixers can network together by daisy-chain. This is only supported in Switched network mode (default). |
| Direct to Computer | Connect the Primary port directly to a computer. |
Star Configuration (Recommended)
Daisy-Chain
Direct to Computer
Avoid the following setups that will render the network unusable:
Do not connect the primary to the secondary port of the same device.
Do not connect the two ports to the same switch.
Do not connect mixers together in a loop.
The Primary and Secondary ports require dedicated network switches in Redundant Audio and Split modes.
Isolated Networks for Each Port in Redundancy and Split Modes
For the most reliable Redundant network, it is recommended to set up both networks without a DHCP server. Connect each unit to a network switch without DHCP or to a router with DHCP disabled.
If it is not possible to disable the DHCP server, configure the mixer to a static IP address:
Warning: Do not reconnect mixers to the network until the network configuration is the same for all units.
Note: Use caution when operating a Link Group in a Redundant network. If a Link Group goes down, there will be temporary audio loss on both ports while the group reconfigures.
Gigabit equipment is strongly recommended for Dante network. If this is not possible, configure the 100 Mbps network with the following guidelines:
Caution: Do not form Link groups on a 100Mbps network, as this will cause increased traffic and will exceed the network bandwidth.
Latency is the amount of time for a signal to travel across the system to the outputs of a device. To account for variances in latency time between devices and channels, Dante has a predetermined selection of latency settings. When the same setting is selected, it ensures that all Dante devices on the network are in sync.
The latency setting for Dante devices should be set according to the number of switches in the network. The SCM820 network card has an internal switch chip and counts as a switch. For example, one SCM820 connected to an external switch equals two switches.
Go to Dante Controller to change the setting.
Warning: Do not reconnect mixers to the network until the network configuration is the same for all units.
| Latency Setting | Maximum Number of Switches | |
|---|---|---|
| 1 Gbps Network* | 100 Mbps Network | |
| 0.25 ms | 3 | - |
| 0.5 ms (default) | 5 | - |
| 1 ms | 10 | 2 |
| 2 ms | 10+ | 5 |
*Strongly Recommended
Audinate software provides additional function and control of the Dante digital audio network. Visit Audinate's website at www.audinate.com for software installation instructions, additional digital audio networking capabilities and troubleshooting help.
Dante Controller (DC) is a free software program by Audinate that is used to configure and manage a network of Dante devices. Use it to route channels between Dante-enabled devices and to monitor the status of the device, clock, and network.
For proper functionality with the SCM820, use Dante Controller version 3.4.0.0 or higher. Go to Audinate's website for download and installation instructions.
Dante Virtual Soundcard (DVS) software turns a computer into a Dante-enabled device, allowing digital audio traffic to be transmitted and received using the standard Ethernet port.
On Windows, DVS can select Steinberg’s ASIO audio interface or Windows Driver Model (WDM). On Mac OSX, the DVS uses the standard Core Audio interface.
If additional channels are needed, multiple mixers can link together to create a larger automatic mix. To form a link, Dante-enabled mixers are connected to a gigabit network and assigned to a link group. This enables up to 12 mixers (96 channels) to contribute to the same mix from anywhere on the network.
Mixers in the same link group operate under shared IntelliMix settings. These settings are defined by the first mixer to join the group. When mixers are added, their IntelliMix and network settings are reconfigured to match the group's settings. IntelliMix settings can then be changed from any mixer, automatically updating the rest of the group.
Link Groups are created by using the auto link button on the mixer back panel. Once a mixer joins a group, its front panel Network Audio and Automix Link LEDs will illuminate green. Up to 12 mixers can join a group at a time.
Ensure the Link Group setup meets the following requirements:
The auto link setting enables SCM820s to automatically form a link group when they join the network. No additional setup from the web application is required.
Select the auto link button on the mixer back panel. It automatically links to other mixers with this function enabled.
Note: Only the first 12 mixers that enable Auto-Link will join the group. If the group is full and an additional mixer attempts to enable Auto Link, it will remain as a Stand-Alone device.
Enable Auto-Linking
The Local/Global setting determines whether each linked SCM820 Mix Output contains only its own program output, or that of all linked mixers. Go to the Output tab of the web application to select the mix output.
Note: The Master level control is independent of the Local/Global setting. The output level and limiter setting of each mixer is affected only by its own Master control.
Global (default)
All linked channels appear at the mixer outputs. This is the default setting for the mixer.
Local
Only its own eight input channels appear at the mixer's Mix Outputs.
The aux channel can be set to Local or Global from web application > Inputs Tab. Local Aux keeps the Aux signal from appearing on the mix output of other networked boxes
When using DFR channels or setting up a sound system an external processor/equalizer, begin by setting the SCM820 to Manual. This activates (gates open) all channels, so every possible feedback path is open.
After equalizing the sound system and "ringing out" the room with the feedback controller, set the mixer back to an IntelliMix mode.
Shure ULX-D™ Digital Wireless offers uncompromising audio clarity and extremely efficient RF performance with rugged, intelligent, encryption-enabled hardware. The SCM820-DAN can provide automixing for the Dual or Quad ULX-D receiver by connecting to the Dante digital audio network.
IntelliMix can be used as a processing insert on an analog console or over the digital audio network. Be sure to set the console inserts to post-fader. If this is not available, be sure to mute audio at the SCM820 in order to remove the signal from the automix.
Analog Insert
Dante Insert
The logic functions of the SCM820 expand the mixer's range of installation and control options. These functions can be hardwired or configured in the web application.
The following hardware logic functions are available for each channel:
Gate Out
Follows channel gating and goes to logic "low" (sinks current) when microphone is gated on. 500 mA of current sinking ability is provided.
Mute In
Applying logic "low" (from GATE OUT or a switch closure to logic ground) gates channel off (channel output is fully attenuated).
Override In
Applying logic "low" (from GATE OUT or a switch closure to logic ground) forces channel on. When both Mute and Override are activated, Mute takes precedence.
Logic Ground
Logic ground is distinct from the SCM820 audio ground. Make all logic ground connections to this pin, including power supply ground of external logic circuitry. To avoid switch clicks, do not connect logic ground to audio, chassis or rack grounds.
This section contains suggestions on the uses of the SCM820's logic capabilities. For additional suggestions and solutions to installation problems, contact Shure's Systems Support.
The chairperson can, by activating a switch, silence all other microphones and be heard without interruption.
An alternative to a switch is to set the Chairperson Mute to Auto. In this setting, when the chairperson's microphone activates, all other microphones mute automatically.
Remote indicators can be used to indicate when a talker's microphone is on. Connect the LEDs and a 5-volt supply to the GATE OUT pin. To avoid switching clicks in the audio output, do not ground the power supply negative terminal in the audio system or rack ground.
Important: If a single cable is used for the microphone audio signal and the LED dc power, separate shielded pairs must be used. Failure to carry the DC power on a shielded pair may result in audible clicking due to capacitive coupling between the DC power lines and microphone lines.
Select Always On for the channel(s) that should remain open ().
Some applications require a loudspeaker to be placed near each talker to provide audio reinforcement, or to permit telephone conversation or conference monitoring. Each loudspeaker can cause feedback unless it is automatically switched off when the talker near it speaks. To provide this function, connect the GATE OUT terminal of each channel to a separate loudspeaker muting relay.
NOTE: A diode across each relay coil is required to suppress inductive voltage spikes which may damage the SCM820.
An alternative to creating a circuit is a Logic Controlled Relay, such as the Radio Design Labs (RDL) ST‑LCR1.
Dante-enabled mixers integrate software applications such as MS Teamstm, Skypetm, Zoomtm, and WebExtm. This enables multiple microphones to participate in a teleconferencing event.
Trademarks: Trademarks are the property of their respective owners.
DFR uses Shure’s patented Adaptive Notch Filter algorithm to discriminate between feedback and non-feedback sounds. It automatically detects feedback and deploys narrow-band notch filters at the feedback frequencies. DFR filters are narrow enough to prevent any coloration of the audio program.
No sound system (the combination of microphones, mixing, signal processing, power amplifiers, loudspeakers and room acoustics) produces an absolutely flat response. When the level of a sound system is increased, the frequencies at which peaks occur will be the first to exceed the threshold of feedback. The DFR attenuates these frequencies, flattening the response of the sound system and enabling operation at a higher overall level.
DFR is available for the SCM820 on firmware versions 1.1.0 and higher. For a unit running an earlier firmware version, use the Shure Update Utility application to update the mixer to a new firmware. The application is available from www.shure.com/software.
Use DFR as the initial processor on any channel that receives signal from a live microphone where feedback is problematic. When DFR detects feedback, it inserts a shallow, narrow filter into the audio path to reduce gain at the feedback frequency. This filter is called a notch filter, due to the narrow section of the frequency spectrum it affects. The notch automatically deepens if feedback continues on that frequency.
Digital Feedback Reducer will not enable you to increase system gain beyond the physical limits of the sound system. In most cases, you reach a point of diminishing returns after five to eight notch filters are set. This is because there are usually only a few dominant peaks in the response of the system. In most cases, you can expect a 6 dB to 9 dB improvement in gain-before-feedback by using the DFR. When you are ringing out the system and notice that many frequencies feedback simultaneously, you have reached the point of diminishing returns. If at this point the system still has insufficient gain before feedback, other changes must be made to the sound system, such as changing the placement of the microphones and/or loudspeakers.
There are two basic ways in which to set-up the DFR to reduce feedback; the Ring-Out Method and the Insurance Policy Method:
Note: Depending on the setup of the sounds system, the main PA signal may be separate from the monitor mix signal. Each feedback path should include a DFR for the maximum gain before feedback.
Two DFR blocks are assignable to any channel input or mix output. When using two or less microphones, assign the DFR to those channels to prevent feedback from routing to the mix bus. Additionally, if a microphone is designated for a chairperson or host, DFR should be applied to that channel to ensure that remains stable and does not feed back.
Apply DFR to a mix bus when using multiple non-stationary microphones or when trouble frequencies are feeding back simultaneously in multiple microphone channels.
The DFR offers two width options for notch filters. By default, filters in the DFR are deployed as High Q filters. As a high Q filter gets deeper its Q increases up to 101 (1/70th of an octave). You can also set filters to deploy at Low Q. Low Q filters affect a slightly wider range of frequencies by maintaining a Q of 58 (1/40th of an octave) as they deepen. To change the setting for an existing filter, select the Q-Width drop-down menu in the filter row.
New Filter Q: This setting determines the Q width for new Unlocked (Dynamic) frequencies as deployed by DFR.
The SCM820 application enables comprehensive control of the mixer. The application is accessible from any computer. Use the application for the following functions:
| Tabs | The control application is separated into tabs for different functions:
|
| Channel Name | Channel names can be customized with up to 31 any characters in length except '=','.' or '@'. |
| Source | Sets the audio input to one of two sources:
|
| Input Gain Level | Selects the analog input gain level for each channel.
Note: Gain is disabled when the audio source is set to Network. |
| Low-Cut Filter | Ideal for attenuating low-frequency vibration caused by table vibrations or air-conditioning rumble. Adjust the frequency of the 12 dB/octave filter from 25 - 320 Hz.
|
| High-Shelf Filter | For tempering sibilant speech or enhancing the sound of off-axis microphones. Use this to boost or cut the signal by 12 dB at 5 kHz.
|
| Phantom Power (+48V) | When selected, the button illuminates green to indicate 48 V phantom power is supplied to the microphone. Use this setting for condenser microphones. Note: Disabled when Input Gain Level is set to Line (+0dB) or Audio Source is set to Network. |
| DFR Enable/Disable Button | When Digital Feedback Reducer (DFR) is assigned from the DFR tab, an enable/disable button appears in that channel strip.
|
| Channel On Indicators | The two indicators illuminate green when the channel is open to that mix bus (Mix A or Mix B). When set to Dual Mixer, the A and B indicators function separately for each mix. |
| Clip Indicator | Illuminates when the signal is clipping the input preamp. The light will stay lit as a warning for 2 seconds. Select a lower Input Gain Level to avoid clipping. |
| Input Meter | Displays signal level information. The meter is customizable for he following options:
|
| Channel Fader and Gain Value | Adjusts the channel volume from -110 dB to +18 dB. |
| Mute Button | Mutes the audio for that channel. A muted channel still can still be soloed to the headphones for monitoring. Channel Mute Control can be set to one of two places from the IntelliMix tab:
|
| Aux Routing | Routes the aux channel to the selected mix output. The aux channel routes without automixing to the mix outputs. |
| Aux Link Mode | Defines the aux channel routing when the device is in a Link Group:
|
| Input Meter Mode | Determines if the channel meters are before (Pre-Fader) or after (Post-Fader) the channel's volume knob/fader. |
| Mixer Type | The SCM820 can be set to operate as a single or dual mixer:
|
| Mix Modes | The Mix Mode sets the IntelliMix configuration to determine the way the channels are mixed to the master outputs. When an adjustment is made to any IntelliMix preset, the mode automatically changes to Custom. See Mixer Modes section for configuration details of each preset. Press the mode button to highlight which channels are routed to that mix. A colored bar in the channel strip correlates to the assigned mix output. To view the other mix's settings, click on the mode for that mix. Note: When set to Single Mixer operation, Mixes A and B are the same. |
| Channel Name | Displays the channel name as defined in the Inputs Tab. |
| Routing | Routes the channel to the Mix A or Mix B output. The routing options depend on the Mixer Type:
|
| Gating Logic | When the mixer is set to Dual Mixer operation, this setting determines whether Mix A or Mix B controls the hardware functions (IntelliMix Direct Output), indicators (Channel Status LEDs) and channel Logic pins. |
| Always On | The Always On setting forces a channel to stay open continuously in the mix. Note: A channel that is set to Always On still contributes to and is affected by the IntelliMix. For example, NOMA still applies to Always On channels. |
| Chairperson |
Additional settings can be assigned to the channel(s) for special privileges. Override:The channel gates open regardless of NOM setting (number of open microphones). Mute:All other channels mute when this channel gates open. There are two types of Chairperson Mute:
|
| Enable/Disable Button | Click this button to enable or disable the DFR notch filtering. It automatically turns on when DFR is assigned to a channel. When disabled, the DFR filters are turned off.
|
| Channel Assignment | Assign the DFR block to an input channel or mix bus. |
| Freeze | Click this button to prevent both the deployment of new filters and the automatic adjustment of existing filters. Freeze the DFR to keep it from deploying filters for program material that contains sounds that closely resemble feedback (such as guitar effects, synthesized tones, flute or pipe organ). The button appears lighted in blue when the freeze feature is enabled. During this time, filters remain manually adjustable. |
| Clear All | Clears all settings in the DFR block and reverts all filters back to Unlocked (Dynamic). |
| Channel Name | Displays the channel name as defined in the Inputs Tab. |
| Direct Output Selection | The direct output can be routed from one of five stages in the signal path:
|
| Direct Output On Indicator | Illuminates when the channel is present at the direct output, depending on IntelliMix gating. |
| Clip Indicator | Illuminates when the input signal overloads the digital-to-analog converter. The light will stay lit as a warning for 2 seconds. |
| Direct Output Meter | Displays the channel's direct output signal level. |
| Mix Output Name | Mix names can be customized with up to 31 any characters in length except '=','.' or '@'. |
| DFR Enable/Disable Button | When DFR is assigned from the DFR tab, an enable/disable button appears in that channel strip. Select to toggle the state:
|
| Lim (Limiter) Indicator | Illuminates to indicate that the signal has exceed the limiter threshold, engaging the limiter. |
| Clip Indicator | Illuminates when the signal has clipped the outputs, holding for two seconds. |
| Output Meter | Displays the output signal level. |
| Fader and Gain Value Box | Adjusts the mix volume from -110 dB to +18 dB. |
| Limiter Activation Box | Activates the limiter when selected. |
| Lim Threshold | Set the limiter threshold from -2 to -50 dBFS for the mix outputs. The level is indicated by the blue triangle next to the meter. |
| Output Level | Selects the output level of the mix outputs. Set according to the input of the connecting equipment. There are three settings: Line (-0dB) (default), Aux (-20dB), Mic (-46dB). |
| Mute | Mutes the audio output for that mix. |
| Link Mode | Defines the audio content for the mix outputs when the device is in a Link Group.
|
Warranty Information Read-Only
| Device Name | Device names can be customized with up to 31 any characters in length except '=','.' or '@'. |
| Device Serial Number | Unique identification of the mixer. Use the number to register the unit at shure.com. |
| Firmware version | Displays the firmware version of the device. |
| Meter Type | Selects the information displayed on the channel input meters on the Input tab:
|
| Headphone Mode | Routes audio to the headphone output from one of two stages in the signal path:
|
| Enable Software Meters | When selected, this turns on all metering in the control application. Enabling meters increases network traffic. (This does not affect the hardware metering.) |
| No Lights Mode | Turns off all visual indicators on the mixer (except the Power LED on the front panel). |
| Flash LEDs | When clicked, this commands the mixer's LEDs to flash for easy identification. |
| Reboot Device | Reboots the mixer. The mixer will reboot in Standalone mode. |
| Reset Device to Factory Defaults | Returns the mixer to default factory settings (clearing the password and device and channel names). The mixer will reboot in Standalone mode. |
| Configuration | Determines the routing of Shure Control and Dante Audio & Controller data from the two network ports. See Port Configuration for details. Follow these steps to change the Configuration mode:
Warning: Do not reconnect mixers to the network until the network settings are the same for all units. |
| Problem | Indicator | Solution |
|---|---|---|
| Distorted audio | Channel Status LED = Flashing Red |
|
| Mix Output meter = Clipping |
|
|
| No Audio/Faint Audio | Channel LEDs in Channel Meter mode (front panel) = Off |
|
| Mix Output meters = Off |
|
| Problem | Indicator | Solution |
|---|---|---|
| Can't Connect to the web application | Device not appearing in Shure Web Device Discovery application |
|
| Device appears in Shure Discovery application, but web browser cannot connect to the device |
|
|
| web application is taking a long time to load | Browser opens but the web application is slow to load |
|
| web application is slow | Indicators are moving slowly or not displaying in real time. |
|
| Problem | Indicator | Solution | |
|---|---|---|---|
| Network audio is missing or distorted | Network Audio LED | Green |
|
| Flashing Green |
|
||
| Red |
|
||
| Off |
|
||
| No audio output for mixers in a Link Group | AutoMix Link LED | Green |
|
| Flashing Green |
|
||
| Off |
|
||
| Problem | Indicator | Solution |
|---|---|---|
| Can't make adjustments to the mixer | lockout LED = Red |
|
| No LEDs are turning on | Power button = On |
|
For additional Troubleshooting assistance or further information on complex installations, contact Shure to speak with a support representative. In the Americas region, call Systems Support group at 847-600-8541. For users in other locations, go to www.shure.com to find support contact for your region.
For digital audio networking help, advanced networking guidelines and Dante software troubleshooting, visit Audinate's website at www.audinate.com.
An error message is generated on the Channel LED rings when operating or environmental conditions occur that could potentially harm the mixer. These types of messages indicate the mixer has experienced a critical failure. Before calling Shure System Support, try these basic debugging tools:
Note: To temporarily clear an error message until troubleshooting can be conducted, simultaneously press the Channel 1 knob and Front Panel Mode selector.
One example of an error message is the Device Overheating message. This appears on the channel LEDs in the following pattern as illustrated in the drawing. For this message, it is recommended that the device be immediately cooled down to avoid permanent damage. If the problem persists, follow the steps listed above to try to clear the message.
Device Overheating Error Code
| Hardware Kit (SCM820, SCM820-DAN) | 90A20082 |
| Hardware Kit (SCM820-DB25, SCM820-DAN-DB25) | 90BA8100 |
| Ethernet cable | 95D15103 |
| Power Cable | region dependent, see table |
| Power Cable by Region | Part Number |
|---|---|
| US | 95B8389 |
| Brazil | 95A14336 |
| Argentina | 95A14335 |
| Europe | 95C8247 |
| UK | 95A8713 |
| Japan | 95B9021 |
| China | 95B9073 |
| Korea | 95B9074 |
| Australia | 95A9128 |
20 Hz to 20 kHz (±1 dB)
20 Hz to 20 kHz, A-weighted, typical
| Analog-to-Analog | 110 dB |
| Analog-to-Dante, Dante-to-Analog | 113 dB |
20 Hz to 20 kHz, A-Weighted, one channel open
| Line (-0dB) | Aux (-20dB) | Mic (-46dB) |
|---|---|---|
| −90 dBV | −110 dBV | −135 dBV |
20 Hz to 20 kHz, A-Weighted, input terminated with 150Ω, digital gain at +18 dB
| Line (+0dB) | Mic (+26dB) | Mic (+46dB) |
|---|---|---|
| −93 dBV | −118 dBV | −130 dBV |
1 kHz, +4 dBu out, mix output (MASTER) at +0 dB
<0.05%
150Ω balanced source, at 1kHz
>70 dB
Non-inverting, any input to any output
44 mm x 483 mm x 289 mm (1.7 in. x 19.0 in. x 11.4 in.), H x W x D
5.5 kg (12.0 lbs)
Steel; Extruded aluminum
100 to 240 V AC, 50-60 Hz, 1 A
−18°C (0°F) to 63°C (145°F)
−29°C (-20°F) to 74°C (165°F)
| Configuration | Impedance | Clipping Level | ||
|---|---|---|---|---|
| Line (+0dB) | Mic (+26dB) | Mic (+46dB) | ||
| Active Balanced | 5 kΩ | +20 dBV | −6 dBV | −26 dBV |
48 V DC, selectable per channel, 14 mA
max.
Mic level settings only. Phantom power automatically switched off in LINE position.
| Configuration | Impedance | Clipping Level |
|---|---|---|
| stereo, unbalanced | 10 kΩ | +10 dBV |
| Configuration | Impedance | Max Output Level | ||
|---|---|---|---|---|
| Line (-0dB) | Aux (-20dB) | Mic (-46dB) | ||
| Active Balanced | 350 Ω | +20 dBV | 0 dBV | −26 dBV |
| Configuration | Impedance | Max Output Level |
|---|---|---|
| Impedance Balanced | 150 Ω | +20 dBV |
6.35 mm (1/4") TRS, 100 mW, 350 Ω, dual mono (will drive stereo phones)
24-bit, 48 kHz, 113 dB dynamic range
typical
32-bit
From channel input to mix output, Estimated Nominal, ±0.1 ms
| Single Device ( ms) | In a Link Group ( ms) | |
|---|---|---|
| Analog to Analog | 0.51 | 0.76 + 4TN |
| Analog to Dante | 0.29 | 0.54 + 4TN |
| Dante to Analog | 0.28 + TN | 0.53 + 5TN |
| Dante to Dante | 0.06 + TN | 0.31 + 5TN |
TN = Network latency in milliseconds, as set in the device preferences page or Dante Controller.
Note: Dante network latency is typically associated with the receiving device.
| Gain Adjustment Range | −110 dB to +18 dB |
| Low Cut | Corner: 25 Hz to 320 HzSlope: 12dB/octave |
| High Shelf | Corner: 5 kHzSlope: 12dB/octaveGain: −18 dB to +18 dB |
| Gain Adjustment Range | −110 dB to +18 dB |
| Low Shelf | Corner: 25 Hz to 20 kHzSlope: 12dB/octaveGain: −18 dB to +18 dB |
| High Shelf | Corner: 25 Hz to 20 kHzSlope: 12dB/octaveGain: −18 dB to +18 dB |
| 6-Band PEQ | 25 Hz to 20 kHz, ±18 dBBandwidth: 1/70 to 4octaves |
| Limiter | Ratio: 10:1Threshold: −50dBFS to −2dBFSAttack: 0.1 msDecay: 100 ms |
| Number of DFR Blocks | 2 |
| Number of Notch Filters | 1 to 16 (default) |
| Notch Filter Bandwidth | High Q: 1/70th octave (Q=101)Low Q: 1/40th octave (Q=58) |
| Notch Filter Depth | 0 db to −18 dB in 0.5 dB increments |
| SCM820 | Single Port, 10/100 Mbps Ethernet |
| SCM820-DAN | Dual Port, Gigabit Ethernet, Dante digital audio |
Cat 5e or higher, shielded, 100 m maximum
DHCP, link-local, static
| Port | TCP/UDP | Protocol | Description | Factory Default |
|---|---|---|---|---|
| 21 | tcp | FTP | Required for firmware updates (otherwise closed) | Closed |
| 22 | tcp | SSH | Not supported | Closed |
| 23 | tcp | Telnet | Standard console interface | Closed |
| 68 | udp | DHCP | Dynamic Host Configuration Protocol | Open |
| 80* | tcp | HTTP | Required to launch embedded web server | Open |
| 427 | tcp/udp | SLP† | Required for inter-device communication | Open |
| 443 | tcp | HTTPS | Not supported | Closed |
| 161 | tcp | SNMP | Not supported | Closed |
| 162 | tcp | SNMP | Not supported | Closed |
| 2202 | tcp | ASCII | Required for 3rd party control strings | Open |
| 5353 | udp | mDNS† | Required for device discovery | Open |
| 5568 | udp | SDT† | Required for inter-device communication | Open |
| 8023 | tcp | Telnet | Debug console interface | Password |
| 8427 | udp | Multcast SLP† | Required for inter-device communication | Open |
| 64000 | tcp | Telnet | Required for Shure firmware update | Open |
| Port | TCP/UDP | Protocol | Description |
|---|---|---|---|
| [319-320]* | udp | PTP† | Dante clocking |
| 4321, 14336-14600 | udp | Dante | Dante audio |
| [4440, 4444, 4455]* | udp | Dante | Dante audio routing |
| 5353 | udp | mDNS† | Used by Dante |
| [8700-8706, 8800]* | udp | Dante | Dante Control and Monitoring |
| 8751 | udp | Dante | Dante Controller |
| 16000-65536 | udp | Dante | Used by Dante |
*These ports must be open on the PC or control system to access the device through a firewall.
†These protocols require multicast. Ensure multicast has been correctly configured for your network.
DB25 Connectors
 |
This symbol indicates that dangerous voltage constituting a risk of electric shock is present within this unit. |
 |
This symbol indicates that there are important operating and maintenance instructions in the literature accompanying this unit. |
The equipment is intended to be used in professional audio applications.
Note: This device is not intended to be connected directly to a public internet network.
EMC conformance to Environment E2: Commercial and Light Industrial. Testing is based on the use of supplied and recommended cable types. The use of other than shielded (screened) cable types may degrade EMC performance.
Changes or modifications not expressly approved by Shure Incorporated could void your authority to operate this equipment.
Industry Canada ICES-003 Compliance Label: CAN ICES-3 (B)/NMB-3(B)
Authorized under the verification provision of FCC Part 15B.
Please follow your regional recycling scheme for batteries, packaging, and electronic waste.
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential 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. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
U.S. patent numbers
Publications