Audio Database

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A speaker system incorporating new technologies such as A.D. M.C.

Woofer
A 31 cm cone type woofer is installed in the low range.

New Aramid Hybrid Honeycomb Cone is used for the diaphragm.
This diaphragm uses Aramid Hybrid FRP for the front skin and cellulose fiber skin for the back skin.
Aramid Hybrid FRP has an intra-ply structure consisting of aramid aromatic polyamide organic fiber with high strength and moderate internal loss, and amorphous silica inorganic fiber with high rigidity. In DS-77Z, the rigidity of amorphous silica has been further improved by 15% compared to conventional products. By hybrid weaving these fibers, the skin material achieves both higher specific elastic modulus and optimum loss factor.
By using the traditional honeycomb structure of the front skin and the cellulose fiber lining skin with excellent internal loss, the fusion of high rigidity and high internal loss is realized.

The newly developed A.D. M.C. (Advanced Magnet Circuit) is used for the magnetic circuit of Woofer.
Magnetostriction is caused by the distribution of DC magnetic flux, which is the driving energy, AC magnetic field generated by the current applied to the voice coil, and AC components in the magnetic flux. Diatone analyzed this using computer technology such as the finite element method, and developed A. D. M. C. which effectively suppresses magnetostriction.
First, we examined the shape of the center pole to enhance the symmetry of the DC magnetic flux distribution across the voice coil. At the same time, we placed a conductive short ring on the center pole to offset the AC magnetic flux from the voice coil, thereby suppressing the magnetostriction caused by the superposition of DC and AC magnetic flux.
Furthermore, by reducing the disturbance of the DC magnetic flux due to the AC magnetic flux in the magnetic circuit, the drive energy is stabilized and distortion is reduced at a high level.

High-rigidity R. S. frame is used in the frame part to suppress unnecessary resonance.

midrange
The mid-range is equipped with a 10 cm cone type squaker.

For the cone part of the diaphragm, we use an intra-ply hybrid diaphragm made by hybrid weaving of organic fiber aramid and inorganic fiber PAN-based high-strength carbon fiber. By combining PAN-based high-strength carbon fiber with extremely high specific elastic modulus and organic aramid with high strength and moderate internal loss, we realize a diaphragm that takes advantage of each other's characteristics.

The center diaphragm of the diaphragm uses S. R. titanium dome, which has high specific elastic modulus and internal loss by surface hardening of titanium.

The edge uses a tangential edge that has been coated with a special damping material to improve responsiveness.
In order to control resonance, this edge has a laminated structure of two tangential cloths to realize flattening of characteristics and reduction of strain.

The voice coil uses an extremely high-purity oxygen-free copper of 6N (99.9999%) to realize a sound with little distortion.

The R. S. frame, which strongly supports the magnetic circuit and controls resonance, has been adopted in the frame part for higher rigidity.

Tweeter
A 2.5 cm dome type tweeter is installed in the high range.

Boron D. U. D. dome is used for the diaphragm.
Boron is second only to diamond in hardness and has excellent characteristics such as sound velocity. At the same time, it has physical properties closer to porcelain rather than metal. In addition, DS-77Z has been reviewing boron in various ways, focusing on characteristics such as high specific elastic modulus, high durability and weather resistance, and proper sound control.
In addition, the D. U. D structure that integrates the diaphragm and voice coil bobbin transfers driving force to the diaphragm without loss, and realizes high limit frequency, linearity, and improved input resistance.

The frame structure adopts D. M. method, and the plate part which is a part of magnetic circuit is directly mounted.
The DS-77Z has a hybrid structure in which the entire plate is mounted with aluminum alloy sheathing in order to eliminate resonance of the magnetic circuit components. In addition to high rigidity, the DS-77Z has an appropriate damping property.

Network
A crimping wiring method is used for connection of the network section, and an independent power supply method is used to eliminate interference between each unit and network.
In addition, the split structure with separate woofer elements prevents noise from becoming cloudy due to magnetic flux leakage.

Laminated oriented cores are used for coils, oxygen-free copper wires are used for electrical wires, and capacitors and resistors are also carefully selected.

Enclosure
The front baffle uses a 2-side round baffle to suppress sound quality degradation caused by the diffraction effect of sound waves.

The enclosure has a highly rigid distributed resonance structure utilizing our unique analytical technology.
In addition, a 30 mm thick baffle is adopted to further increase rigidity, and resolution is improved.

Other
The DS-77Z has a full-scale anti-magnetic design.

There were 2 kinds of variations for the speaker stand sold separately.

Model Rating
Method 3-way, 3-speaker, airtight system, bookshelf type, magnetic shielding design (EIAJ)
Units Used For low band : 31 cm cone type
For Medium Range : 10 cm Cone Type
For high-pass : 2.5 cm dome type
Nominal impedance 6 Ω
Playback frequency band 35 Hz to 35 kHz
Output sound pressure level 91dB/W/m
Crossover frequency 500 Hz, 4 kHz
Max Input 230W(EIAJ)
External dimensions Width 400x Height 700x Depth 330 mm
Weight 29.0kg
Attachment OFC speaker cable
Speaker Stand DK-DK-77Z (2 pcs 1 set, ¥ 35,000)
External dimensions Width 410x Height 264x Depth 330 mm
Weight 10.0kg
Speaker Stand DK-DK-77V (1 set of 2, ¥ 35,000)
External dimensions Width 430x Height 250x Depth 340 mm
Weight 8.0kg