SB-G90E-K Speaker System TECHNICS

Grand Class Speaker System SB-G90.

A floor-standing speaker that guarantees precise reproduction of apparent source locations and full spatial expression.

A speaker system with a single-point source.

For full surround reproduction, the front of the sound wave emitted from the speaker should be adjusted to any position of the listener, so that a single-point source is provided. Based on the linear phase concept, the SB-G90 loudspeakers are equipped with newly developed two-way concentric cone drivers (including a midrange driver and tweeter) aimed at reproducing sound at high speed and with improved sensitivity in the higher registers.

Phase Precision Driver (concentric two-way driver)

The tweeter uses a lightweight anodized aluminum dome diaphragm with high stiffness. The speaker produces a wide frequency range up to 100 kHz thanks to a new dome shape optimized using simulation, as well as by achieving greater uniformity of phase properties using a phase equalizer. In addition, the SB-G90 loudspeakers use high linearity long coils in which magnetic fluid has been injected into the magnetic slots to limit temperature rise, thus providing better power linearity. These features ensure a high frequency response reproduction that is stunning in detail and beauty.

Like the tweeter, the midrange driver uses an anodized lightweight aluminum dome cone with high stiffness. The magnetic circuitry used allows for low distortion and increased driver power due to the use of large magnets, copper caps and long coils with high linearity. In addition, the subframe is constructed of hard cast parts with vibration-dissipating arms, which completely eliminates even the quietest unwanted resonant sounds. These features enable the midrange to be reproduced with superb precision.

In addition, the mid-range diaphragm uses a cone shape with the center of sound production in the axial direction closer to the center of sound production of the tweeter, and the axial position of the dome tweeter direction located at the center of the mid-range diaphragm is precisely adjusted to achieve linear phase imaging by integrating sound in each band without delay. Also, the inner end of the midrange diaphragm has a smooth shape, so there is no degradation of the tweeter's sound characteristics, and the diaphragm is made to transmit the sound emitted from the tweeter directly to the listening position. As a result, the sound of the midrange and high frequencies is reproduced with superb precision and excellent clarity.

Balanced Speaker Mounting Architecture (BDMA)

In the conventional way of mounting a loudspeaker assembly to a baffle, the center of gravity of the assembly was far away from the support points, so that the forces acting on the voice coils during driving of the loudspeaker created vibrations in the whole assembly. This caused interference with the sound waves produced by the diaphragm, leading to poor sound quality. In addition, the loudspeaker assembly attached to the fenderwell provides a configuration in which vibrations are easily transferred from the loudspeaker assembly to the fenderwell, producing unnecessary vibration sound from the fenderwell - while degrading sound quality.

With the balanced mounting architecture, the loudspeaker is attached to an auxiliary de-embed installed inside the column at the loudspeaker's center of gravity, resulting in reduced vibration of the loudspeaker. In addition, because the loudspeaker is not attached to the front of the fenderwell, unwanted vibrations from the loudspeaker assembly to the fenderwell are reduced. This reduces the level of distortion of the sound waves produced by the diaphragm and reduces unwanted vibration sound from the surround, which positively affects the reproduction of the sound field with excellent reproduction of the location of apparent sources providing impressive realism and clarity to visualize even the finest sonic details.

16-cm long-throw woofer with low distortion

The woofers incorporate elements such as dual magnets for high power handling and magnet systems with long voice coils of high linearity, copper caps and short aluminium rings. This newly developed long excursion diaphragm system achieves bass reproduction with a large dynamic range while maintaining extremely low distortion and excellent frequency response even at high amplitudes. In addition, the hard cast frame design dissipates resonance, completely eliminating even the smallest unwanted resonant sounds. A lightweight dome diaphragm made of rigid anodized aluminum ensures tonal uniformity in the mid and high registers.

This translates into strong and powerful bass.

High-quality circuitry

The high-precision network circuit is the result of repeated design and listening processes to maximize the performance of each speaker unit and achieve a balanced sound. High-quality parts, such as the polypropylene-coated capacitors, the coreless inductor, and the OFC wire used in the connection, were carefully selected after testing their properties.

To prevent the loudspeaker units from being affected by the vibrations generated in the cabinet, the power supply system is mounted in a special chamber separate from the loudspeaker units, which allows the sound to have a suitable climate.

High rigidity cabinet

The strength of the loudspeaker cabinet is provided by a cross-braced construction with auxiliary baffles, to which the loudspeakers are attached. Each speaker unit uses a separate auxiliary fence to minimize vibration between the speaker units. In addition, the innovative use of two types of absorbent acoustic materials when optimally placed inside the loudspeaker suppresses standing waves and reduces incidental sound from reflections within the loudspeaker.

In addition, polyurethane (PU) coatings on the surface of the column dampen column vibrations for high precision elimination of unwanted sounds. These features produce sound with a wide field and excellent imaging.

Main Features:

- Point source speaker system

- Wide bandwidth sound reproduction with low distortion

- Phase Precision Driver (concentric two-way speaker unit)

- 16-cm long-throw woofer with low distortion

- High quality network circuitry

- Balanced Speaker Mounting Architecture (BDMA)

- High rigidity cabinet

- High-gloss black lacquer finish

- Magnetically mounted fabric grille

Technical specifications

Type: 3-way 4-way Bass Reflex (including 2-way coaxial for midrange and tweeter)

Speaker units:

Woofer: 16 cm, cone x 2

Midrange / High range: 16 cm, cone x 1 and 2.5 cm, dome x 1

Boundary frequencies: 480 Hz, 3.2 kHz

Frequency range: 27 Hz-100 kHz (-16 dB), 32 Hz-85 kHz (-10 dB)

Sound pressure level: 88 dB /2.83 V (m)

Impedance: 4 Ohms

Input power (IEC): 100 W (rated), 200 W (maximum)

Recommended amplifier power: 40 - 200 W

Dimensions (W x H x L): 302 x 1114 x 375 mm (including grille, connectors and spikes)

Weight (1 column): approx. 32 kg

Accessories:

Spike x 4,

Spike pad x 4,

Spacer x 4,

Bottom plate x 4,

Screw for bottom plate x 12,

Rubber feet x 4,

Instruction manual x 1,

Grille x 1,

Cleaning cloth x 1