Fostex NF-1, Технический белый лист

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Tangential design, 5 pcs.
Tangential design, 10 pcs.
Up-roll, UP
Up-roll, DOWN
FEM simulation of load-displacement relationship
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Displacement[mm]
L o a d [ m N ]
FEM analysis of edge-displacement relationship
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2nd order differential
2nd order
differ
ential
Tangential design, 5 pcs.
Tangential design, 10 pcs.
Up-roll, UP
Up-roll, DOWN
L o a d [ m N ]
Evaluation result of 2nd-differential of bi-linearity of an edge
Simulation of a rolling edge
The opposite end rises Pushed at one point
Cone
Reduction in
anti-resonance
at high
frequencies:
Added strength
and a shift to
disperse at high
frequencies
prevent any
natural high peaks
from being
generated, in
contrast to rolled edges. Chances will be remote
that peaks and dips will take place in the frequency
response, and smooth characteristics will be
achieved as with HP system diaphragms. In this
way, our philosophy of elimination of physical
distortion due to components ranging from
diaphragms to edges has been brought into
existence, allowing for natural and higher fidelity
reproduction.
Figures 10 and 11 show FEM analysis results of the
acceleration response, evidencing a high level of
responsiveness which used to be a mere gleam in
the sound engineers' eyes.
Improvement of amplitude response:
It is seen that suspension characteristics, being a soft
clipping type which works to gradually restrict
movement when the magnitude is symmetrical and
large, are ideal.
These characteristics are of particular importance to
monitor speakers, in the sense that they do not permit
listeners to perceive distortion if subjected to excessive
input power.
Improvement in rolling:
This tangential design is strong enough for the plane
dividing the rolled edges in a tangential manner not to
yield to horizontally applied stress. Rolling is unlikely
to occur to this UDR tangential edge even when a high
input power is applied, while a contact by the voice
coil with stationary structure of a speaker is
commonplace with conventional rolled edges.
Figure 9
Figure 10
Figure 11
No resonance is observed on the entire
circumference, nor is there any
axis-symmetry resonance.
Presence of an inflection point is apparent.
Rapid change starting at this inflection point develops harmonic distortion.
Input produces only a gradual change.
Figure 12
Figure 13
Figure 14