Setup For Multiple Thunderbolt And Usb Interfaces - MOTU 1248 User Manual

SETUP FOR MULTIPLE THUNDERBOLT AND
USB INTERFACES
It is possible to connect multiple MOTU interfaces
directly to your host computer through multiple
Thunderbolt and USB ports. However, there are
several disadvantages to using any of these direct
connection schemes:
The audio interfaces will not be clocked to one
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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 43-45. 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
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one audio interface to another. You are better off
using the AVB network connections shown on
pages 43-45, 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 multiple MOTU AVB interfaces with
Thunderbolt connectivity (1248, 8M, 16A or
112D) 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, your MOTU
interface operates as a USB 2.0 device, even when
connected to a USB 3.0 port. USB 2.0 provides
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enough bus speed for several USB 2.0 devices, but
due to your MOTU interface's high-performance
requirements for real-time operation and low
latency timing, we recommend the following:
Do not connect more than two units to your
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computer's USB 2.0 or 3.0 port(s).
When two units are connected with USB 2.0,
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don't connect other USB 2.0 or 3. 0 devices, such as
external hard drives.
For best results, establish clock synchronization
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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 as an AVB Ethernet audio
interface ("AVB Ethernet audio interface setup" on
page 43), 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 interface to the S3's extra
network port (which is a built-in switch). The Mac
can see both 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 62.
Mixing and matching audio interfaces
You can mix and match MOTU audio interfaces.
For example, you could connect a 1248 through
Thunderbolt and another MOTU audio interface,
such as a 24Ao, through USB 2.0.
H A R D W A R E I N S T A L L A T I O N