Biamp Tesira EX-UBT User manual

Using the Tesira EX-UBT
The EX-UBT is a compact remote expander that uses the AVB
networking protocol to extend USB and/or Bluetooth
sources back to a rack-mounted Tesira server-class
device. A standard USB cable connects the host computer
to the EX-UBT. CAT5e cabling or better is required for the
network connection, with a maximum distance of up to 100
meters (328 ft) allowed to the equipment rack. The EX-
UBT is an IEEE 802.3at Class 2 device requiring 7 watts
of power from a gigabit PoE-capable switch or mid-span
injector.
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eatures
USB
The EX-UBT USB port acts as a client to the connected host computer. Within Tesira software, the USB can be
configured to pass audio in/out according to one of the following options:
• Mono (1 input x 1 output)
• Stereo (2 inputs x 2 outputs)
• Multi-Channel (8 inputs x 8 outputs)
◦ Note that the Biamp Tesira USB audio driver is required for Windows OS when using multi-channel mode. Mac
OS supports multi-channel audio natively. Windows can only support mono and stereo audio natively without
needing to install a USB driver.
When configured as a speakerphone, the EX-UBT uses Human Interface Device (HID) communication that can
synchronize privacy mute state and volume control if the UC application supports this communication. HID mute
synchronization and AEC offloading are supported by various UC platforms as noted:
This list is inclusive of formal support and interoperability; other devices and platforms not in this list may honor HID
mute synchronization. Some devices prefer 16 bit over 24 bit audio formatting. Tesira W 4.0.3 and newer will auto-
negotiate with the host UC/PC device for the proper format. This can be viewed in Windows audio device settings or
similar of the host device:
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Bluetooth & N C
Bluetooth capability may be enabled/disabled when the EX-UBT is configured in Tesira software. The Bluetooth module
supports the following Bluetooth subset profiles:
• Hands- ree Profile (H P)
• Advanced Audio Distribution Profile (A2DP)
◦ A2DP is supported as an audio sink, and allows the following codecs to be received:
▪ SBC
▪ Qualcomm® aptX™ audio
▪ AAC
Bluetooth pairing may also be made via pre-configured Near ield Communication (N C) tags. N C tags allow users
with N C capable/enabled devices to quickly pair with the EX-UBT by tapping their device to the tag. Instructions for
enabling the N C function will vary by device. Note that Apple® devices do not support N C-assisted compatibility at
this time.
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Each EX-UBT ships with two N C tags that have been write-protect configured with the default hostname of the
associated EX-UBT.
Software & programming
Configurations for the Tesira EX-UBT are available from the Object Toolbar via the Telephony/Communications menu
item:
When the Tesira EX-UBT object type is selected from the Audio Object Toolbar, the EX-UBT Initialization dialog window
is displayed:
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Users may check to use USB, Bluetooth or both.
USB Channel Count - This allows the user to select between
three different channel configurations:
•Mono 1 input x 1 output channel
•Stereo 2 input channels x 2 output
channels
•Multi-channel 8 input channels x 8 output
channels
USB Connection Type - The two Speakerphone modes
provide single or stereo audio input and output streams for
use with a soft codec application on a host computer. The
USB Input represents the incoming audio from the soft codec,
and the USB Output is used to send audio to the far side.
Speakerphone: Disables Computer AEC – In this
mode, the Acoustic Echo Cancellation (AEC) function
will be provided by the AEC block in the Tesira DSP. A
control message is transmitted to the soft codec via the
USB link telling it to disable its internal AEC.
Speakerphone: Enables Computer AEC – This mode
is for situations where the soft codec will provide the
AEC function.
Line In/Out – This mode provides up to eight channels of audio. Combinations of 2, 4, 6 or 8 total USB
channels can operate in fixed 24 Bit, 48 kHz.
Mute USB inputs as a group - Selecting this mutes all USB input channels when the mute state of a single input
channel is changed. This selection is checked and cannot be deselected if either of the Speakerphone USB
terminal types is selected. It is also checked by default if the Line In/Out USB terminal type is selected.
Mute USB outputs as a group - Selecting this mutes all USB output channels when the mute state of a single
output channel is changed. This selection is checked and cannot be deselected if either of the Speakerphone
USB terminal types is selected. It is also checked by default if the Line In/Out USB terminal type is selected.
Notes on host operating system controls:
• "USB host" refers to USB on the computer.
• In Multi-Channel 8x8 Line In/Out mode, changes to the USB host mute and record level controls will
be ignored by the EX-UBT.
• Balance controls will not be synchronized between the USB input block and the USB host when in
speakerphone mode (only playback levels are).
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DSP blocks
The following images show the DSP blocks associated with different Initialization options:
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or more details regarding EX-UBT logic, please reference tesira-help.biamp.com.
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USB Details
When the EX-UBT is connected to a host computer, it will enumerate as an Echo Cancelling Speakerphone or sound
device as defined during block initialization. Notice the sound device name also includes the unique serial number of the
EX-UBT device by default.
If the user would like to change the name of the EX-UBT device as it presents to the host computer, Tesira 3.14 allows
custom USB device naming within the block dialog window:
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The EX-UBT device will reboot itself implementing the USB Device Name change and the host computer* will update
with the new USB Device Name:
*(This feature had mixed results when tested on Mac OSX using 1-7 channel USB block. 8 channel EX-UBT USB block reportedly worked well.)
When the EX-UBT blocks are initialized as a speakerphone and selected as the Default Audio Device in the Windows 10
host computer, mute and volume synchronization occurs upon USB connection. This means that the host computer
volume level will synchronize with the volume level of the EX-UBT USB input block in the Tesira configuration. Volume
and mute changes made on the host computer or the EX-UBT USB input block will remain synchronized. This behavior
is demonstrated in this short video. Note that files created with Tesira 3.17 or newer will set the USB block minimum
level to -50 in order to map more accurately to the host PC volume ramp range and rate. This example video
demonstrates the Tesira 3.17 behavior.
When privacy mute is selected in Skype or Business*, Microsoft Teams Room System* or Google Hangouts Meet
System*, the mute state of the EX-UBT Output block mute will track accordingly. Similarly, if the mute logic input of the
EX-UBT USB Output block is triggered high, the privacy mute indication in Skype or Business or Microsoft Teams will
follow.
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*The synchronization of level and mute states is possible via USB HID communication. Performance may vary with
applications not listed in the UC compatibility table.
EX-UBT USB Tips:
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• A logic-driven preset can initialize the USB input block-level providing a more consistent user experience.
◦This short video provides an example of the concept.
• Some integrated UC systems require mute state synchronization between the UC client and the table
microphones. Please see this article for further details on how to accomplish this.
Bluetooth details
The Bluetooth Control/Status block offers four user-settable parameters:
•Bluetooth Name - Defaults to Tesira EX-UBTxxxxxxxx (where 'xxxxxxxx' represents the EX-UBT's serial
number) and can be customized via the 'Edit' button.
•Inactivity Timeout - An active Bluetooth connection will be disconnected after the defined time period. When
set to 0 seconds, a connection will not timeout.
•Bluetooth Radio - Enabled/Disabled
•Discoverable - Enables/Disables
discoverability of the EX-UBT.
The Bluetooth Status sub-section offers additional
information regarding the paired/connected Bluetooth
device:
•Connected status & Bluetooth Host device
name.
•Streaming status & active Streaming Profile
details.
•MAC Address of the Bluetooth Host device
•Optional Disconnect button.
*Note, third-party control systems can poll, set, and/or subscribe to these attributes via Tesira Text Protocol (TTP).
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Bluetooth Best Practices:
• Set the Bluetooth name to the meeting room
name so that users can identify and associate
it accordingly.
• Enable Bluetooth and make the EX-
UBT Discoverable at appropriate times. If a
conference room is powered down, it may
make sense to disable the Bluetooth Radio.
• Setting the Inactivity Timeout to a value greater than 0 will automatically disconnect Bluetooth devices if they
are not actively streaming. This will free up the connection if users forget to disconnect. Values between 60
and 300 are recommended.
• Setting the Inactivity Timeout to 0 seconds will allow a connected Bluetooth host to remain connected
indefinitely.
• Be sure to test various sources and applications because the 'Streaming' indication may vary with each
application or platform.
• Bluetooth connections are on a "first come, first served" basis. If a host device is already connected, another
Bluetooth device cannot bump them off. The Disconnect button can be utilized to bump active connections
and permit a new device to connect.
Gain Structure & dB S
Bluetooth and USB source signals are digital ull-Scale signals commonly referred to as dB S. The audio meters in
Tesira software are dBu meters. The following image provides a visual for correlation:
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The USB and Bluetooth sources from the EX-UBT are digital (dB S) sources. When the host device is set to 100%
volume, the signal will likely average -12 dB S but will appear on Tesira audio meters as +12 dBu. If the host volume is
set to 50%, the signal will average approximately -24 dB S or 0 dBu.
As a point of comparison, most analog microphones have their input gain adjusted so that a good signal will meter
between 0 and 6 dBu. When mixing dB S signals with microphone or line-level dBu signals in the Tesira configuration,
consider using attenuation or dynamics to level match these different source types.
The EX-UBT Bluetooth input block does include a Peak indication LED. This indicator will illuminate when the signal
peak is 3 dB below clip (0 dB S). A brief flickering of this indicator is acceptable and typically indicates the host
Bluetooth device volume is likely at 100%. Turning down the volume on the host Bluetooth device will lower the signal
accordingly. Based on the expected system performance, users may consider attenuating the Bluetooth input block as
shown in the following image:
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Powering the EX-UBT - PoE
The EX-UBT is a Power Over Ethernet device which classifies as 802.3at Class 2 (7W). Please note that there are
manufacturing and design differences between mid-span PoE injectors.
When directly connecting the EX-UBT (or any Tesira expander) to a Tesira ORTE or Tesira Server-IO AVB port, the
mid-span PoE injector must support 1 Gbps data link speed. If the mid-span PoE injector does not support 1 Gbps, the
EX-UBT power LED will illuminate steady yellow but the LED on the AVB RJ45 port will remain dark indicating no data
activity.
LED Indication
• Also available at tesira-help.biamp.com
Troubleshooting
General
• When troubleshooting HID mute synchronization on various UC clients and hardware iterations, it is often helpful to
test and compare the mute synchronization with a wired Microsoft Teams certified headset vs. the EX-UBT.
• Be aware that UC platforms vie for the HID mute synchronization on a host machine. This means that only one can
have access to the HID communications at a time and it is common for conflict to occur if two or more UC platforms
(S B, Teams, Zoom, Hangouts, etc.) are running at the same time on the host machine. It might be worth closing all
UC platforms before testing any HID mute synchronization.
USB Inspection Tools
•USB Device Tree View
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◦ If interested, download this video demonstration: Simulating and Identifying EX-UBT flapping in Tesira Event
Logs.mp4
•USB Device Viewer
Multi-channel audio
• When connected (/disconnected) to (/from) a PC the USB device should be added
(/deleted) in Windows PC Device Manager's Universal Serial Bus controllers list (as a
USB Composite Device) as well as the Audio inputs and outputs list in real time.
• The Biamp Tesira Control Panel for the Biamp ASIO driver (in the Windows tray) allows
you to select the ASIO buffer size. A larger buffer will increase latency to the USB
recorder but will reduce load on the CPU. Larger buffer sizes may reduce clicks, pops,
glitches, or dropouts.
• When verifying USB output to computers it can be useful to route a tone generator to the
USB output channels. A 1kHz tone at +12dBu routed to each USB output channel will clearly show activity on
meters on the recording PC. On some recording platforms the meters may not indicate low "background level"
activity so providing a high-level slate tone allows easy and repeatable validation of connected channels. Note that
a +12dBu signal from the Tesira tone generator to a USB meter should indicate about -12dB S.
• 3rd party audio metering software can be used to independently verify the USB audio input if there is a question of
the customer's recording software accurately receiving input. Be certain the 3rd party software is configured for the
correct number of channels, the correct sample rate, and is assigned to monitor the correct USB inputs. Options
that have been seen to work in the past include:
◦https://pas-products.com/multimeterbridge.html
▪ Under Settings > 'Select audio input' choose '8 channels'
▪ Under Settings > 'Level Outfit' - Meter Ballistics options choose 'Peak dB S'
◦https://www.orban.com/meter
▪ In the Settings tab choose Channels = '7.1 Surround' and the desired Audio Device input channels
▪ In the Meters tab be sure to Start metering using the button at the bottom center
urther reading
•EX-UBT Operation Manual
•Gain Structure - urther details on dB S etc.
•Design Library example file
•http://blog.biamp.com/poe-vs-poe-the-struggle-is-real/
•Design Guide - Tesira - Open Office
•Specifying PoE Switches for Biamp Tesira devices
•Microsoft Teams Rooms Package
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