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© 2000 Merging Technologies
Sphynx User Manual
What i
s
the best setup (again, stand-alone-no computer) for measuring and testing the audio coming out AES
and Analog?
The example c) above should be a pretty good example of how to setup a Sphynx for a stand-alone A/D and D/A
quality measurement. This setup allows both a A/D path and a D/A path to be measured, using for example an Audio
Precision equipment which can generate test tones in AES-EBU format, while analyzing the returned analog line
signals or the opposite as well (generating analog line signals and analyzing returned digital AES-EBU signals)
I want to place the Sphynx in a machine room, what is the maximum cable length I can use for the Optical
cables?
When using Keops and the Sphynx for example, we have tested optical runs of up to 10 meters, using standard APF
(All Plastic Fiber) cables without problems. The official maximum length recommended by Alesis (the makers of
ADAT) is 6 meters.
Beyond 10 meters (and up to 1000 meters), the setup requires the addition of two Merging
Onouris
LDS (Long
Distance System) converters.
Contact Merging if you would like to run optical cables longer than 10 meters.
Can you solve the optical cable distance by simply substituting glass optical cables for the plastic cables?
This is not a recommended practice. If you need length, only switching to glass optical cable is not enough.
You will need to change the optical ‘driver’ and ‘receiver’ as well.
Merging provides the whole system, composed of two glass optical cables and one
Onouris
LDS at each end.
This system allows a bi-directional link of up to 1000 meters.
Why AutoDetect SR mode doesn't work on incoming AES-EBU signals in Video sync mode?
The AutoDetect SR mode does work based on an AES-EBU signal, but only when the
AES
sync mode is selected.
In
INT
,
ODI
or
VIDEO
sync mode the sample rate selection is based on the signal present at the
ODI
-
A
input.
What are the main symptoms of improper video sync setup?
The first symptom is the
LOCK
LED, which could blink or stay off in case of an improper video sync setup.
Check the video connections and make sure that the signal is properly terminated.
It is not recommended to daisy chain devices. The best is to connect each device directly to the video sync generator
and terminate the connection on each device.
A second information is the M
ONITOR OUT
LEDs which indicates whether the incoming ADAT signals present on the
ODI
-
A
and
ODI
-
B
inputs are synchronous with the Sphynx clock or not.
If the M
ONITOR OUT
LEDs blink, there must be a problem in your synchronization setup.
What would be a typical use of the AES-EBU reference input on the back of Sphynx?
Some studios are using an AES-EBU reference signal as a house-sync, instead of a Wordclock or a video reference.
How many channels of audio can you get via S/PDIF?
The S/PDIF format allows transmitting up to two audio channels on a single coaxial or plastic optical cable.
Under what circumstances would one want to enable dither?
The dither is disabled by default, which correspond to a use in a 24 bit recording environment.
If your recording system is limited (or that you want to limit it) to 20, 18 or 16 bit, you should set the Sphynx A/D
dither to the corresponding word length.
Summary of Contents for Sphynx
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