AYRE QB-9DSD - Manual (Page 17)

uses the “Full Speed” mode of USB 1.1 and is
capable of transporting all sample rates up to 96
kHz. To play sample rates higher than 96 kHz
requires “Class 2 Audio”, which uses the USB 2.0
“High Speed” mode to transport data at higher rates
as long as the operating system also supports Class 2
Audio.
For Mac, this requires OS X version 10.6.4 or
higher. None of the Windows operating systems
supports “High Speed” mode for audio via the USB
ports. Ayre has made available a custom USB driver
that is compatible with Windows XP, Service Pack
2 and later. Please refer to the Ayre website to
download the required file and also additional
instructions to play sample rates beyond 96 kHz:
www.ayre.com/usb.htm
The QB-9
DSD
will first attempt to connect to the
computer via the High Speed USB mode with Class
2 Audio. If the computer does not include USB 2.0
connectors, the QB-9
DSD will “fall back” to Full
Speed USB with Class 1 Audio and be limited to
96/24 files. (DoP files require High Speed USB.)
Earlier “non-DSD” units require manual speed
configuration. Setting the rear panel toggle switch
“up” to “Rsrv A” selects Full Speed USB with Class
1 Audio, while setting the switch “down” to “Rsrv
B” selects High Speed USB with Class 2 Audio,
required for sample rates beyond 96 kHz. However
the operating system must also support Class 2
Audio either with its native USB Audio drivers or
by installing the add-on driver for Windows.
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