D'Amore engine'ring SMD IM-SG, Руководство пользователя

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18
The Significance of f
S
Subwoofer - The f
S
value of a subwoofer is the frequency
at which the cone naturally resonates, or vibrates at. This
is
one of the factors that determine how low a subwoofer
will play. Example: A subwoofer with an f
S
of 35 Hz is
going to have a harder time trying to reproduce a 25 Hz
tone than a subwoofer with a f
S
of 20 Hz would. The f
S
is
also one of the main factors that go into calculating
subwoofer enclosure volume and tuning frequency.
Midbass / Midrange - The f
S
value of a midbass or
midrange speaker can be looked at as a limit for where the
highpass crossover should be set. Example: A 6.5 inch
midrange was measured to have an f
S
of 60 Hz. This
speaker should be crossed over (high pass filtered) higher
than 60 Hz to protect the driver from over excursion and
damage. We suggest setting the high pass filter on
midbass drivers
octave to 1 octave higher than the
driver's f
S
for best power handling. Use octave higher if
using a 24dB/Octave crossover, and 1 octave higher if
using a 12dB/Octave crossover.
This is not law by any
means, just a suggestion and very good place to start. If
the midbass driver has its own sealed or ported enclosure
it's possible that lower crossover frequencies can be used.
24dB/octave Example: For octave higher, take the
measured f
S
and multiply by 1.41. So for measured f
S
of
60 Hz, crossover should be set at 60 Hz X 1.41 = 85 Hz.
12dB/octave Example: For 1 octave higher, take the
measured f
S
and multiply by 2. So for measured f
S
of 60
Hz, crossover should be set at 60 Hz X 2 = 120 Hz.