Controlling Audio
76
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High-Pass Filter
Passes signals with frequencies higher than
a certain frequency (fc: cutoff frequency)
and attenuates signals with frequencies
lower than the cutoff frequency. Use this to
pass only high-frequency signals. Use this in
the following cases for example:
–
For extracting the frequency band for
separate tweeters. By extracting the
specific frequency band, level adjustment
can be made to the frequency band
individually.
–
The sound may be muddy when you play
back low frequency sound. This occurs
when frequencies below the speaker
capacity is inputted. To cancel this, use the
high-pass filter to cut off the frequencies
below the speaker capacity.
［dB］
［Hz］
fc
●
High-Shelving Filter/Low-Shelving Filter
These filters reduce or increase signals
above or below a certain frequency (fc:
cutoff frequency), which create shelves in
the frequency spectrums. A high-shelving
filter reduces or increases the frequencies
above the target frequency and a low-
shelving filter reduces or increases the
frequencies below the target frequency. The
low shelf controls the lower frequencies and
the high shelf controls the high frequencies.
Use these in the following cases for
example:
–
When you want to change the volume of
the tweeters, for example when they are
close to your ears and are sounding too
loud.
–
When you want to change the subwoofer
volume at hand.
［dB］
［Hz］
fc
●
Peaking Filter
The frequencies in the vicinity of a certain
frequency (f0: center frequency) are
boosted or attenuated. Use this in the
following cases for example:
–
When you want to control a narrow range
of frequencies to correct the frequency
abnormality in the car.
–
To diminish a chattering noise from the
speaker by attenuating the frequency
range of the noise.
–
To adjust of the sound balance of the
whole range between the low end and the
high end.
［dB］
［Hz］
f0
●
Low-Pass Filter
Passes signals with frequencies lower than a
certain frequency (fc: cutoff frequency) and
attenuates signals with frequencies higher
than the cutoff frequency. Use this to pass
only low-frequency signals. Use this in the
following cases for example:
–
For extracting the low frequencies band
for a subwoofer.
–
For extracting middle/low frequencies
when you are using speakers with
separate tweeters and you want to output
the high frequencies to the tweeters and
output the middle/low frequencies to the
woofers.
–
To cut the high frequencies when they are
too loud.
［dB］
［Hz］
fc
