User Manual

A White Paper Of The Installation Series Loudspeakers
<Combination of different enclosure-size models>
3. Design concept
According to the experiment mentioned above,
we recognized a phase control as the one of the
most important factor. Then, we especially
focused on the balance of a phase and tone
control, and aimed to realize both the "In Phase
Concept" and "family sound concept". The
followings are details of each concept.
1) Phase control
(1) In Phase concept
From the result described above, the phase
characteristics of all speakers in this series must
be the same.
- Same phase characteristics between the same
enclosure models that have different
directivities
- Same phase characteristics between passive
and bi-amp models with the same enclosure.
- Same phase characteristics between high-
power and middle-power (will be available in
the autumn of 2005) models with the same
enclosure.
- Same phase characteristics between different
enclosure models.
- The phase difference between speakers at 2
kHz must be within 90 degrees.
(2) Using the minimum phase change
type
There are two methods of controlling the phase
characteristics of multi-way speaker systems.
A. Minimum phase change type
This method aims for minimizing the phase
change between 20 Hz and 20 kHz. It realizes
the smoothly changed phase characteristics
within one lap (180 degrees to -180 degrees).
It is likely to have the level-down problem of
the amplitude characteristics in the frequency
range where low-frequency and high-frequency
drivers are crossed over.
B. Same phase slope type
This method aims for the smooth phase change
over the whole frequency range. It does not aim
for minimizing the phase change.
By adding a delay to the low-frequency driver to
match the phase slope of the low-frequency
driver to the slope of the high-frequency driver,
the phase characteristics of two drivers are
smoothly joined.
With this method, at the boundary of the phase
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