5.0
Quickstart Guide : Digital Audio Synchronization and TimeCode
Quickstart Guide
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Audio Connections
Many users will have A/D Converters for feeding analog audio sources into Pyramix, and D/A Converters
for playing analog audio out of Pyramix. In this case, connect your analog audio sources to the A/D Converter analog audio inputs, and the A/D digital audio output(s) to the Mykerinos digital audio input(s). Similarly, connect the Mykerinos digital audio output(s) to your D/A Converter digital audio input(s), and the D/A
Converter analog audio outputs to your studio monitors or recorders. It may be also be useful to connect
the stereo mini-phone output on the Mykerinos card to either stereo headphones or a stereo monitor console input. The source for this jack can be configured inside the Pyramix software.
Digital Audio Synchronization and TimeCode
THERE MUST BE ONLY ONE SOURCE OF SYNC FOR AUDIO AND TIMECODE
Digital audio relies on extremely accurate timing. In any digital audio system there can only be one source
of sync at one time. This is particularly important when planning multi-machine systems. If TimeCode is not
locked to the same sync source as the digital audio then either the audio will work properly, or the TimeCode. But NOT BOTH AT THE SAME TIME.
Ideally, in any system with more than one device, there will also be an independent source of sync. E.g. a
word-clock generator with multiple outputs. Each device is fed by a single output and configured to use this
source as its sync reference.
Sync, Video and Time Code Connections
In any digital audio system, it is VERY IMPORTANT all interconnected units are locked to the same sync
reference. A digital audio signal itself can sometimes be used as the master sync source, but a high stability video or wordclock signal is usually preferable.
The Mykerinos board can be configured inside the Pyramix software to act as either a sync master, or to
slave to a variety of incoming signals.
Decide which device in your system will provide the master sync reference, then ensure that all other digital
audio devices in your system take their synchronization from it. This will require routing appropriate cables
--whether digital audio, video or wordclock cables-- to the various other devices and may also involve a
separate sync reference generator and or distribution amplifiers.
If Pyramix is configured as the master (Internal sync), other digital audio devices will probably be able to
lock to the digital audio output from Pyramix. However, Pyramix can also be configured to output a wordclock signal at the Video output BNC connector (Pyramix Synchronization option required).
If Pyramix is configured as a slave to an external device, Various synchronization signals can be accepted.
• To lock to incoming digital audio, connect an appropriate digital audio signal to a Pyramix digital
audio input.
• To lock to incoming video, connect an appropriate video signal to the Pyramix Video Reference
input (Pyramix Synchronization option required).
• To lock to incoming wordclock, connect an appropriate master wordclock signal to the Pyramix
Video 2 Input (Pyramix Synchronization option required).
• To set the termination jumpers provided on the Mykerinos board, please see the Mykerinos User
Guide.
• Pyramix can either output or lock to incoming SMPTE / EBU TimeCode.