MOTU 828es, User Manual

Page: 37 / 120

H A R D W A R E I N S T A L L A T I O N
37
SETUP FOR MULTIPLE INTERFACES
It is possible to connect multiple MOTU interfaces
directly to your host computer through multiple
USB (and Thunderbolt) ports. However, there are
several disadvantages to using any of these direct
connection schemes:
■
The audio interfaces will not be clocked to one
another and may be susceptible to drift, unless you
use external word clock connections (if available).
You are better off using the AVB network
connections shown on pages 34-36. In this setup,
the interfaces are very tightly synchronized with
each other (measured in pico seconds) through
their network connections.
■
You will not be able to route audio directly from
one audio interface to another. You are better off
using the AVB network connections shown on
pages 34-36, which allows you to route audio
streams (hundreds at a time) directly among
interfaces with near-zero latency.
Connecting multiple interfaces using
Thunderbolt
If you have other MOTU interfaces with
Thunderbolt connectivity (1248, 8M, 16A, 112D,
624 or 8A) and your host computer has two or
more Thunderbolt ports, you can connect one
interface to each port, either directly or at the end
of a Thunderbolt daisy chain (on either port or
both ports).
Connecting multiple interfaces using
Thunderbolt and USB
Another way to operate multiple interfaces on the
same host computer is to connect the first
interface to a Thunderbolt port and the second to
a USB 2.0 (or 3.0) port.
Multiple interfaces and USB
When connected through USB, the 828es operates
as a USB 2.0 device, even when connected to a
USB 3.0 port. USB 2.0 provides enough bus speed
for several USB 2.0 devices, but due to the high-
performance requirements of the 828es for real-
time operation and low latency timing, we
recommend the following:
■
Do not connect more than two units to your
computer’s USB 2.0 (or 3.0) ports.
■
When two units are connected with USB 2.0,
don’t connect other USB 2.0 or 3. 0 devices, such
as external hard drives.
■
For best results, establish clock synchronization
with other interfaces connected to the same
computer. You can use word clock, S/PDIF, optical
or AVB to achieve clock synchronization.
Multiple AVB Ethernet audio interfaces
When operating 828es as an AVB Ethernet audio
interface (“AVB Ethernet audio interface setup” on
page 34), multiple AVB audio interfaces can be
connected using a MOTU AVB Switch (or any
3rd-party AVB switch), and the Mac can see all of
them through their AVB connection. For example,
you could connect an Avid S3 console to the Mac,
and then connect a MOTU 828es to the S3’s extra
network port (which is a built-in switch). The Mac
can see both 828es and S3 for audio I/O. For best
results in this scenario, be sure to use OS X 10.11
(El Capitan) or later. See “Syncing multiple AVB
audio interfaces connected to a Mac” on page 50.
Mixing and matching audio interfaces
You can mix and match MOTU audio interfaces.
For example, you could connect an 828es through
Thunderbolt and another MOTU audio interface,
such as the Stage-B16, through USB 2.0.