|a price point -- unknown (one set, in the middle 1960s ?)
The floor type speaker system which adopted the
EAS-20PW55 which is a 20cm double cone unit which
consists of a main cone for a low-pass play and a loud-sound cone for a high
region play is adopted as a speaker unit.
Underwriters-Laboratories edge which National developed is adopted as this
unit. Since Underwriters-Laboratories edge can enlarge compliance with
a special plastics edge, even if it does not perform a special manipulation
like before, it can be reducing distortion.
Moreover, the aluminum wire of the high purity is used for the voice
coil, and since it is far lighter than copper wire, it has succeeded in
extending an upper register play threshold.
Since the elastic wave by
which a radiation is carried out from each part of a speaker cone had the mutual
phase difference, the interference was caused on a certain wavelength, it was
affected especially with upper register, and the variation of the frequency
characteristic had occurred.
In order to cope with this, the patent
equalizer ball (low phase equalizer) is attached to the front of a loud-sound
cone, if the diffraction of an elastic wave is used, it is arranging a field, and the loud-sound property is made flat.
The magnetic circuit of gap
flux density 12,200Gauss is adopted.
The enclosure serves as a
bass-reflex type which uses the walnut developed to EAS-20PW55.
material of glass wool is stuck on the interior, and a lusterless color tone and
ornament are given to the sheath.
It is designed make a hard wall meet and
install a backplane.
||1 way, 1 speaker bass-reflex scheme, and a
||For all the bands: 20cm double cone type (EAS-20PW55)
||35Hz - 20000Hz
|A nominal input
||Width 380x height 720x depth of 300mm