Grass Valley DAC-1721 - Manuel

SERIE ( DENSITÉ )
DAC-1721 –Dual AES to analog Converter
Installation and Operation Manual
M698-9900-100
juillet 2002
DAC-1721
Introduction
DAC-1721 is a dual, high quality, digital to analog audio
converter that allows conversion of two AES digital signals to
four analog audio signals. The input sampling rates can be up to
100 kHz including 32 kHz, 44.1 kHz, 48 kHz and 96 kHz. An
internal digital EBU tone generator facilitates alignment of audio
levels. All analog audio output levels may be set individually. A
digital 50/15µs de-emphasis stage may be selected manually or
automatically according to the channel status. Input audio signal
status is also available indicating input signal presence or
overload. The DAC-1721 is compatible with both AES3 and
AES-3id digital audio standards and is housed in a (DENSITÉ)
frame. The ‘double’ rear connector panel depends of audio
standard used.
Features
•
Dual AES3, AES-3id or S/PDIF digital inputs
•
Dual stereo analog audio outputs
•
0 dBFS adjustment from 0 to +24 dBu
•
24 bit D to A conversion
•
32 to 96 kHz sampling rates
•
-96 to +12 dB level adjustment (0.5 dB steps)
•
Soft mute
•
Adjustable presence and overload threshold
•
Internal EBU tone generator
•
Digital 50
µ
15 de-emphasis selectable
•
Settings and adjustments through frame control panel
or remotely
•
Status LED and remote reporting
Microcontroller
Rem Control
Select
Status
OUTPUTS
ANALOG
INPUTS
AES
(110 or 75 Ohm)
Tone
Generator
AES 1
R1
AES
Receiver
L1
24-bit
DAC
R2
L2
AES 2
DAC-1721 Functional Block Diagram
AES
Receiver
24-bit
DAC
Level & Mute
Level & Mute
Tone
Generator
MNTR Intra Frame
Monitoring
Specifications
Inputs (2)
AES3
Level:........................ 0,2 to 7 V pp
Termination: ............. 110 O balanced
AES-3id (S/PDIF compatible)
Level:........................ 0.2 to 2 Vp-p
Impedance:............... 75 O unbalanced
Return loss: .............. > 15 dB up to 12 MHz
Outputs (4)
Signal: ..................... balanced analog audio
Output impedance: ... < 50 O
Max. Level: ............... +24 dBu / 600 O
Processing Performance
Quantization: ........... 24 bits
Sampling: ................. 20 to 50 kHz (128X over-sampling)
................................. 50 to 100 kHz (64X over-sampling)
SNR:......................... 116 dB A weighted
Distortion: ............................- 96 dB
Crosstalk: ............................-100 dB (20 Hz to 20 kHz)
0 dBFS: ...............................0 to +24 dBu (1 dB steps)
Freq. response: ..................± 0.2 dB (20 Hz to 20 kHz)
De-Emphasis:......................± 0.3 dB (50-15 µsec)
Group delay:........................670 µsec @ 48 kHz (˜ 32/FS)
Tone generator:...................1 kHz sine wave interrupted on
left channel EBU R49
(250 ms / 3 s)
Miscellaneous
Signal presence threshold: .from –72 to –54 dBFS
(6 dB steps)
No signal delay:......... .........from 0 to 255 s (1 s steps)
GPI outputs sink current: ....< 40 mA
Power: .................................4.3 W
Specifications are subject to change without notice.