Datasheet

Controller application, to Dante receivers (inputs) on related
equipment. The flexibility of being able to interconnect signals
(create Dante “subscriptions”) between all Dante devices
on a network allows the audio tones to be used for a variety
of purposes. Configuration choices allow the frequency and
level of each sine wave tone to be optimized for use in specific
applications.
Leader Clock Support for Dante
Networks
A core part of the technology underlying Dante audio-over-IP
networking ensures that all connected devices follow a com
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mon timing reference. This is accomplished using the PTPv1
(IEEE 1588-2002) and PTPv2 (IEEE 1588-2008) precision
time protocols. Any connected Dante device can be used as a
Leader clock; there is no requirement that a dedicated Leader
clock device be utilized to realize adequate functionality. How
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ever, the actual performance can vary widely depending on
the specific Dante devices available and the overall number
of Dante devices on a network.
Many Dante devices utilize the 2- or 4-channel Ultimo™ ULT
or UXT integrated circuits to implement Dante connectivity.
While Ultimo devices will fully support Dante audio transport,
they are not well suited to serve as a Leader clock. Ultimo’s
PTP performance is limited and does not have the ability to
synchronize with an external timing reference. Other Dante
devices may use the Brooklyn II module or Broadway inte
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grated circuit to support Dante connectivity. In some cases,
these devices can provide good basic performance as a
Leader clock.
However, problems and limitations may arise when these
devices are called upon to perform “double duty,” serving in
both a primary function (such as analog-to-Dante interfac
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ing or audio signal processing) as well as acting as a Leader
clock. This is understandable as the main purpose of these
devices is to serve functions other than acting as a primary
synchronization reference. Timing related features, such as
allowing connection of a video bi- or tri-level sync signal is
rarely, if ever, supported. And PTP performance can degrade
when the computing power of a device is intended primarily for
handling and manipulating digital audio signals. This can lead
to the required PTP resources being in short supply when the
number of Dante devices that need timing messages moves
Studio Technologies, Inc. Model 5401A Dante Leader Clock, Issue 4, Page 3
into the hundreds. Also, firmware updates, cabling changes,
and other maintenance tasks typically associated with a
general-purpose Dante device would impact the Leader clock
functionality for an entire installation.
The Model 5401A was specifically designed to support a
Dante-based audio system’s Leader clock requirement. And
the unit’s generation of audio tones and implementation of the
word clock output utilize hardware circuitry that is separate
from that associated with its PTP functionality. As such, this
secondary functionality will not interfere with PTP operation.
Unlike a general-purpose Dante device, once mounted in an
equipment rack and the required interconnections are made,
the Model 5401A will perform its tasks without risk of inter
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ruption due to conflicting resource demands.
Flexible Networking Capability
Using the Dante Controller application program, the Model
5401A’s three Ethernet ports can be selected to operate in
one of four modes: Switched, Redundant, Switched+Mgmt,
and Redundant+Mgmt. This should allow virtually any desired
networking implementation to be easily achieved.
By using the Switched or Redundant network modes, separate
network connections will be maintained for Dante audio and
management purposes.
In the Switched mode a single Ethernet connection to either
of the Model 5401A’s two Dante Ethernet ports will provide
Dante Leader clock functionality. The remaining Dante
Ethernet port will provide Dante network “loop-through”
capability and can be used to interface with another piece of
Ethernet-connected equipment. The management Ethernet
port will be used to access the Model 5401A’s monitoring and
configuration webpages.
In the Redundant mode two independent Ethernet connections
are made to the Model 5401A’s two Dante Ethernet ports,
enabling Dante’s redundant networking capability. Again, the
management Ethernet port will be used to access the Model
5401A’s monitoring and configuration webpages.
In the Switched+Mgmt mode a single Ethernet connection
is used for both Dante Leader clock functionality as well as
providing access to the Model 5401A’s management web
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pages. The remaining Dante Ethernet port will provide network
“loop-through” capability and can be used to interface with
another piece of Ethernet-connected equipment.