Roland VS-2000 - Digital Input Signals; Digital Connections; Digital Considerations; The Master Clock

9—Working with Input Signals
Roland VS-2000 Owner’s Manual www.RolandUS.com 135
Digital Input Signals
Digital Connections
The VS-2000 can accept digital audio from an external digital device through its
COAXIAL IN jack. To learn about this jack, see Page 48.
Digital Considerations
This section discusses a couple of issues you should consider to help ensure that your
digital audio is successfully captured by the VS-2000.
Sample Rates
The VS-2000 operates at a sampling rate of 44.1 kHz. As a result, it will successfully
receive only external digital audio that uses that sample rate.
If your source material is at a different sample rate, consider converting the external
audio’s sample rate to 44.1 kHz before bringing it into the VS-2000. There are various
devices and utilities that you can use for this purpose.
Bit Depth
The VS-2000 records audio using 24 bits or 16 bits, according to the project’s recording
mode (Page 102).
If an external digital audio device uses a bit depth that’s higher than your project’s,
dither the device’s output down to the project’s recording resolution before bringing
the audio into the VS-2000. If the device uses the same or a lower bit depth, the
VS-2000 will record the audio as is, at the project’s selected bit depth.
The VS-2000 can also dither its digital output to match a lower bit depth used by an
external digital device receiving audio from the VS-2000—see Page 382.
The Master Clock
In order for two digital audio devices to communicate successfully, they have to both
use the same timing reference, or “master clock.” If they don’t, the digital audio they
exchange is likely to wind up at the wrong pitch, or to have clicks and pops within it.
The master clock timing reference can be produced by the device producing the digital
audio. The timing information, called “word clock,” is sent alongside the digital audio
signal from the source device—the “master”—to the receiving device, called the “slave.”
Who Should Supply the Master Clock?
There are two basic conditions in which you’ll be bringing digital audio signals into the
VS-2000’s digital inputs, and each has its own master clock considerations:
• when its hard disk recorder isn’t being synchronized to an external device
• when its hard disk recorder is being synchronized to an external device
The Digital IN connector of VS-2000 is compatible with 2ch PCM audio only. If the
VS-2000 receives audio signal in other formats (DTS, Dolby Surround etc.), it outputs
such a signal as noise.
Sample rate
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