Manual

Model 5401A User Guide Issue 2, July 2021
Studio Technologies, Inc. Page 7
5401A’s logic circuitry to create the highly
stable word clock output. This ensures that
the word clock output is synchronized with
the unit’s PTPv1 and PTPv2 server func-
tionality.
Audio Tone Generator
The Model 5401A generates eight sine
wave audio tones intended for general-pur-
pose use. These audio tones are available
from the Model 5401A by way of Dante
transmitter (output) channels and can be
connected, using the Dante Controller ap-
plication, 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. Configura-
tion 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-
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 func-
tionality. However, 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 connectiv-
ity. 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 integrated circuit to support
Dante connectivity. In some cases, these
devices can provide good basic perfor-
mance 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
interfacing or audio signal processing) as
well as acting as a Leader clock. This is un-
derstandable as the main purpose of these
devices is to serve functions other than act-
ing 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 com-
puting power of a device is intended pri-
marily 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 into the hundreds.
Also, firmware updates, cabling changes,
and other maintenance tasks typically asso-
ciated 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 implementa-
tion of the word clock output utilize hard-
ware 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 mount-
ed in an equipment rack and the required