NTi Audio Digirator DR2 - Manual (Page 28)

Linear PCM Test Signals
28
5. Linear PCM Test Signals
Signal generation
The Digirator DR2 flexibly generates linear PCM test signals
such as sine, noise or even other arbitrary signals from 48 kHz
wave (WAV) files. The match and lock of the selected sampling
rate to the applied reference signal is handled by an internal
sample rate converter.
This configuration ensures that the generated audio signal
frequency is not dependent on the sampling rate but left un-
changed. The sample rate converter, featuring a high dynamic
range of 144 dB
A
, does not affect the audio signal quality speci-
fication.
Audio frequency range
The generated audio signals feature a bandwidth of 24 kHz,
sine signals can be synthesized up to 20 kHz. Settings violating
the Nyquist theorem are not prohibited as the sample rate con-
verter will simply attenuate these signals. (e.g. Sine signal with
f = 20 kHz at a sampling rate of 32 kHz is attenuated because
sampling rate should be at least twice the signal frequency).
DR2 internal signal flow for linear PCM test signals
Digital Audio
Transmitter
Sample Rate
Converter
Digital Audio
Receiver
Signal
Generator
Analyzer
fs = 48 kHz
32.0 kHz
44.1 kHz (*2 , *4)
48.0 kHz (*2 , *4)
INT
EXT
Video (PAL, NTSC)
Word Clock
AES3, DARS
Digital Audio
Transmitter
Sample Rate
Converter
Digital Audio
Receiver
Signal
Generator
Analyzer
fs = 48 kHz
32.0 kHz
44.1 kHz (*2 , *4)
48.0 kHz (*2 , *4)
INT
EXT
Video (PAL, NTSC)
Word Clock
AES3, DARS
Digital Audio
Transmitter
Sample Rate
Converter
Digital Audio
Receiver
Signal
Generator
Analyzer
fs = 48 kHz
32.0 kHz
44.1 kHz
(*2 , *4)
48.0 kHz (*2 , *4)
INT
EXT
Video (PAL, NTSC)
Word Clock
AES3, DARS
Digital Audio
Transmitter
Sample Rate
Converter
Digital Audio
Receiver
Signal
Generator
Analyzer
fs = 48 kHz
32.0 kHz
44.1 kHz (*2 , *4)
48.0 kHz (*2 , *4)
INT
EXT
Video (PAL, NTSC)
Word Clock
AES3, DARS
fs = 20 - 216 kHz
fs = 20 - 216 kHz fs ≈ 32 - 48 kHz
fs = ~ 48 kHz fs ≈ 48 kHz
Audio signal
Clock signal
not active