D19 MicVALVE
Date printed: 9.2.2000
Additional Information E3/1
3
ADDITIONAL INFORMATION
3.1
What the Heck is Noise Shaping?
It is often necessary to record on digital media accepting only 16-bit signals.
In such cases, the word length of the MicVALVE's 20 bit converters is best
reduced to 16 bit by selecting either the 16NS (Noise shaping) or 16DI
(Dither) modes. Special DSP algorithms are then activated to reduce the
unwanted signal deterioriation which is the result of shortening the word
length.
Dither mode:
Eliminates unwanted truncation artifacts (distortion, noise modulation).
Dither can always be used, independent of any subsequent signal proc-
essing.
Noise Shaping mode:
Further improves the perceptive audio quality, thus best preserving the
original 20-bit signal as it was before being reduced to 16 bit.
However, for
further processing of the signal, always crossfades, fade-ins, or fade-outs
must be used in order to avoid audible clicks.
Both processes bring a distinctive quality improvement as opposed to just
truncating a 20-bit signal.
The diagram below shows the original 20-bit signal (1) and the effect of
truncating to 16 bit (2). Note the distinctive artifacts which contribute to the
degradation of signal quality.
(2)
(1)
D19 MicVALVE
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-90.00
AMP1(dB
FS
) vs FREQ(Hz) & SWI(#)
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100
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