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phono PreAmp Studio USB (English)
9. Application Notes
The
Descratcher
and the
Denoiser
are user-friendly audio-restoration tools based on an ex-
tremely effective signal-processing algorithm. In most cases, they automatically produce good
results. To get the most out of these tools, especially when working with badly damaged au-
dio material, use the following, practical guidelines:
·
Create your recordings using the WAV file format and do not use any editing devices, such
as limiters or compressors, before applying the
Descratching
filter.
·
If the audio material you are restoring contains loud crackling noises, you can limit them
during the digital recording process. We recommend recording various versions with dif-
ferent input amplification levels and comparing the results after carrying out the
De-
scratching
process.
·
To avoid digital distortion, do not set the
Declick
and
Decrackle
parameters too high.
When working with badly damaged material, we recommend finding a good acoustic
compromise between the remaining level of noise and the digital distortions that result
within the signal. Make allowances when trying to improve hopelessly damaged audio
sources, because not even the best tools can bring back the original sound where none is
left.
·
If the sound level and/or sound characteristic changes several times within a recording,
you may want to split the original into separate segments, edit these individually using
various
Denoising
settings and then normalize them.
·
To avoid digital distortions such as whistling sounds and robot-like noises (
time aliasing
),
do not set the
threshold
and
reduction
parameters too high. Start by using a moderate
setting by adjusting the
noise print
to just above the background-noise level (about 10
dB), and then increase the
reduction
parameter gradually. Finally, try determine the opti-
mal correlation between these two parameters.
·
The
Analyzer
can be a great help when optimizing the setting of the
Denoiser
parameter.
During the
Denoising
process, it makes visible the influence that the noise print and the
parameter setting have on the audio signal.
·
If you find the output signal too quiet, increase the
volume
while watching the left and
right sound-level bars. If the red range lights up at all, the volume is set too high and you
have reached the so-called
threshold range
, which can lead to audible distortions.
·
Use the
bass
and
treble
sliders to increase (+) or decrease (-) the values of the bass and
treble frequencies to achieve the tone that sounds best. Be aware, however, that setting
the
bass
and
treble
levels too high increases the output signal volume level and in some
cases can put it into the
threshold range
. In this case, lower the
volume
slider until the
level no longer reaches the threshold range (so that the red LEDs at the top of the level
bars no longer light up).
·
If you do not use the
phono PreAmp Studio USB
to record your audio material, the type of
the sound card and the type of analog/digital converter it uses have an important influ-
