User Manual

User's Guide Fireface 800 © RME
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22.2 Installation
After the driver installation the Fireface 800 is found in the Device Manager (>Settings/Control
Panel/System<), category 'Sound, Video and Gamecontroller'. A double click on 'RME Fireface
800' starts the properties dialog. The well known entry 'Resources' does not exist, becuase the
Fireface is an external device connected to the FireWire Controller. The latter can be used to
check interrupt and memory range.
The newest information on hardware problems can always be found on our website www.rme-
audio.de, section FAQ, Hardware Alert: about incompatible hardware.
In case the Hardware Wizard does not show up automatically after installation of the card,
do not attempt to install the drivers manually! An installation of drivers for non-recognized
hardware will cause a blue screen when booting Windows!
Possible causes for a Fireface not found automatically:
• The FireWire port is not active in the system (drivers of the FireWire PCI or CardBus card
have not been installed)
• The FireWire cable is not, or not correctly inserted into the socket
• No power. After switching the Fireface on, at least the red Host error LED has to be lit.
• The PCI FireWire card is defective
A report about incompatible FireWire 800 controllers is found in the Tech Info FireWire 800
Hardware – Compatibility Problems.
23. Noise level in DS / QS Mode
The outstanding signal to noise ratio of the Fireface's AD-converters can be verified even
without expensive test equipment, by using our famous DIGICheck tool or the record level me-
ter of Steinberg's WaveLab. When activating the DS and QS mode, the displayed noise level
will rise from -109 dB to -104 dB at 96 kHz, and –82 dB at 192 kHz. This is not a failure. This
kind of measurement measures the noise of the whole frequency range, at 96 kHz from 0 Hz to
48 kHz (RMS unweighted), at 192 kHz even from 0 Hz to 96 kHz.
When limiting the measured area to 22 kHz (audio bandpass, weighted) the value would be -
110 dB again. This can be verified even with RME's DIGICheck. Although a dBA weighted
value does not include such a strong bandwidth limitation as audio bandpass does, the dis-
played value of –108 dB is nearly identical to the one at 48 kHz.
The reason for this behaviour is the noise shaping technology of the analog to digital convert-
ers. They move all noise and distortion to the in-audible higher frequency range, above 24 kHz.
That’s how they achieve their outstanding performance and sonic clarity. Therefore the noise is
slightly increased in the ultrasound area. High-frequent noise has a high energy. Add the dou-
bled (quadrupled) bandwidth, and a wideband measurement will show a siginificant drop in
SNR, while the human ear will notice absolutely no change in the audible noise floor.