Inovonics DAVID IV 719 N, Инструкция по установке и эксплуатации

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DAVID IV TECHNICAL SPECIFICATIONS
Some specifications of the DAVID IV are difficult to quantify in
tabular form. Please refer to a corresponding section of the
manual text for additional information or discussion.
GENERAL PERFORMANCE
PLEASE NOTE :
1) The gain structure of an audio processing
system is determined in large part by how
the user sees fit to set numerous ‘subjective’
adjustments. In addition, various processing
functions intentionally upset the tonal bal-
ance (static and dynamic frequency response)
and the waveshape (‘native distortion’ inher-
ent in all program material). Thus it has be-
come customary to establish and publish
performance specifications with audio pro-
cessing features disabled or bypassed. Un-
less otherwise expressed or implied herein,
this is the case with figures shown here, as
indeed seems also the practice of our worthy
competitors.
2) Measurements taken from the Composite/
MPX outputs, or analog/digital line outputs
in the FM mode, presume use of an appropri-
ate de-emphasis network.
Frequency Response:
Composite/MPX Output:
±0.25dB, 20Hz–15kHz
L/R Analog Line Outputs:
±0.25dB, 20Hz–15kHz, FM mode;
±0.25dB, 20Hz–20kHz, Flat mode.
AES Digital Output (Digital Input):
±0.25dB, 20Hz–15kHz, FM mode;
±0.1dB, 20Hz–20kHz, Flat mode.
Noise (unweighted r.m.s.) :
Composite/MPX Output:
SNR >85dB referred to full carrier
modulation.
L/R Analog Line Outputs:
Residual noise better than 100dB below
the output clipping point.
AES Digital Output (Digital Input):
Residual noise better than 130dB below
0dBFS.
Distortion:
Composite/MPX Output:
<0.01% THD
Line Outputs (Digital or Analog):
<0.006% THD
Stereo Separation:
Composite/MPX Output:
>65dB, 20Hz–15kHz assuming the use
of a lab-quality FM-multiplex decoder.
L/R Analog Line Outputs:
>100dB at 1dB below the output clip-
ping level.
AES Digital Output (Digital Input):
>130dB at 0dBFS
MPX Crosstalk:
>78dB Linear Crosstalk (main/sub or
sub/main).
Program Signal Latency
3.6 milliseconds for composite/MPX;
4.2 milliseconds from any input to
any output in any operating mode.
19kHz Stereo Pilot Protection:
>65dB referred to 9% pilot injection.
38kHz Suppression:
>80dB referred to full carrier modula-
tion.
57kHz RDS Subcarrier Protection:
>65dB referred to 5% RDS subcarrier
injection.
REAR-PANEL APPOINTMENTS
Digital Line Input:
The AES3 stereo input (XLR) accepts 16-
or 24-bit program sources at sampling
rates of 32kHz, 44.1kHz, 48kHz and
96kHz. Input gain is adjustable for av-
erage program levels between –5dBFS
and –35dBFS.
Analog Line Inputs:
L/R active balanced/bridging (XLR) in-
puts accept average program line levels
between –15dBu and +15dBu. +26dBu
peak input level.
Digital Line Output:
The AES3 (XLR) 24-bit stereo output
may be adjusted between –20dBFS and
0dBFS, corresponding to full carrier
modulation. The output sampling rate
may be set to follow the Digital Line
Input or forced to 32kHz, 44.1kHz,
48kHz or 96kHz.
(continued)