RME Audio Fireface UFX+, User Manual

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User's Guide Fireface UFX+ © RME 113
Current Fireface UFX+ USB 3 Compatibility Information
¾
Fully compatible to Intel's USB 3 implementation which - on current Windows and Mac
computers - is part of the chipset. USB 3 sockets that are connected via an internal cable
(not directly soldered onto the motherboard) can cause transmission errors (these are
shown in the Settings dialog).
¾ Fully compatible to AMD's USB 3 implementation. USB 3 sockets that are connected via an
internal cable (not directly soldered onto the motherboard) can cause transmission errors
(shown in the Settings dialog).
¾ Compatible to NEC / Renesas USB 3 . Real-world performance and error-free operation
depend on the firmware version, driver version and the PCB layout of the respective exten-
sion card/motherboard.
¾ Fully compatible to Fresco USB 3 chip.
¾ Fully compatible to Via VL912 , very often used in USB 3 hubs
¾
ASMedia - not compatible
¾ Etron EJ168A - not compatible
¾ Texas TUSB7340 - not compatible
¾ Via VL800/805 - not compatible
The Fireface UFX+ is capable of using two different transmission modes to record data. The
UFX+ defaults to
Bulk Mode
, which improves reliability of USB 3 audio tremendously and helps
with both less than perfect cabling as well as critical layouts around the USB 3 chip. The stan-
dard’s default is
Isochronous Streaming
, which is unreliable as per the standard (errors are to
be expected!), unreliable in real-world operation, and not correctly supported by popular USB 3
chips. In very seldom cases, bulk mode can not keep up with the strict timing required for con-
tinuous audio streaming. Then, to make the UFX+ work at all, isochronous mode must be used
(but is still prone to clicks and drop-outs). To make the standard mode available as reference
the Settings dialog includes an option to activate
Isochronous Streaming.
The Fireface UFX+ also supports
USB 2 , where MADI record and playback channels are no
longer available (MADI can still be accessed via TotalMix FX). Good performance and click-free
operation even at low buffer sizes are indeed possible on current computers. However, using
older computers a simple stereo playback might cause a CPU load of more than 30%.
Best USB 2 performance is achieved by connecting the UFX+ to its own bus, which should be
no big problem as most USB 2.0 interfaces are a double bus design. A check in the Device
Manager can be done as follows:
Connect the UFX+ to a USB 2 port
¾ Start the Device Manager, View set to Devices by Connection
¾ Select ACPI x86-based PC, Microsoft ACPI-Compliant System, expand PCI Bus
This branch normally includes two entries of a
USB2 Enhanced Host Controller
. A USB Root
Hub can be seen, which then connects all USB devices, including the UFX+. By reconnecting to
a different port this view shows at which of the two controllers the UFX+ is connected. With
multiple devices it can be checked if they are connected to the same controller.
Furthermore this information can be used to operate an external USB drive without disturbing
the UFX+, by simply connecting the drive to the other controller.
It can also be used to check where and in what combination USB 3 is used. In fact many mod-
ern motherboards have an additional chip to the mostly found Intel chipset, adding further USB
3 ports. But documentation is often unclear about which port/socket is connected to which chip.
By connecting the UFX+ and using the procedure above one can easily see the current connec-
tion, ensuring the UFX+ is really connected to the Intel chipset and not to some other flaky one.