Technics SB-8000

Commentary

A linear phase speaker system equipped with a full-surface drive type leaf tweeter with high frequency characteristics of 125 kHz.

A 36 cm straight cone type woofer is used for the low range that is dedicated to the heavy bass reproduction.

A 16 cm cone type unit is used for the middle and low range.
The narrow edge and low-distortion magnetic circuit realizes low-distortion, clear medium and low sound reproduction that takes advantage of the high frequency reproduction of the leaf tweeter.

An 8 cm cone type unit with excellent matching with the tweeter is adopted for the middle and high range.
The voice coil is specially made to be a small diameter of 19 φ to extend the high frequency characteristics, and realizes smooth frequency characteristics and excellent directional characteristics in the high frequency range as well as an edgeless type support structure.
In addition, the voice coil uses aluminum bobbin with excellent heat radiation and CCAW voice coil with high heat resistance specifications to achieve high input resistance.

A leaf tweeter is used for the high range.
This unit retains the performance of the single unit EAS-10TH1000 announced in 1977, and is refined while taking into consideration the design of the system. The vibration plate is made by coating aluminum foil with a high heat-resistant polymer film and etching the voice coil pattern. This realizes a lightweight vibration plate of 17 mg, about one twentieth of the conventional metal dome type vibration system.
In addition, a large magnet with a weight of 1.2 kg is used for the magnetic circuit, and the structure is sandwiched between I-type and L-type low-loss yokes. Together with the Taber-shaped magnetic pole structure, the leakage of magnetic flux is suppressed, and strong magnetic field generation is obtained.
Unlike the system in which magnets are placed before and after the vibration plate, the vibration plate is strongly driven by a uniform magnetic field at once, and the front surface of the vibration plate is opened widely and uniformly without the influence of the diffraction of sound waves by the magnet lattice.
In the leaf tweeter, a high heat-resistant polymer film based on an analysis of the temperature distribution in the vibration plate during driving was adopted as the vibration plate material. As a result, high input resistance that can withstand 20W (RMS) continuous sinusoidal input has been obtained.
Because there is no mechanical resonance or inductance component in this leaf tweeter, the impedance is constant from DC to 200 khz ultra-high frequency band, and there is no disturbance of frequency characteristics due to impedance fluctuation. Because it is designed with 8 Ω impedance, direct drive is possible without requiring a matching transformer.
The oscillating plate radiation surface is structurally divided into two parts. In order to prevent deterioration of the directional characteristics due to interference at high frequencies, a high-precision aluminum die-cast equalizer fin is installed between the two radiation surfaces to achieve excellent directional characteristics.

The network is specially designed for the linear phase.
In addition, in order to demonstrate the performance of the unit such as the leaf-toter, elements that have been thoroughly examined in terms of performance and reliability are used.

The dumped bass reflex system is used for the enclosure.

With a low inductance cord by arranging two coaxial cables in parallel

Equipped with independent continuous variable level control for tweeters, mid-high and mid-low.

Model Rating

Method	4-way, 4-speaker, linear phase bass reflex system ・ Floor type
Units Used	For low band : 36 cm cone type For middle and low band : 16 cm cone type For Middle and High Areas : 8 cm Cone Type For High Frequency : Full Drive Leaf Type
Playback frequency band	30 Hz ~ 125 kHz
Impedance	8 Ω
Output sound pressure level	93dB/W/m
Allowable input	200W (MUSIC), 100W (DIN RMS)
Crossover frequency	300 Hz, 1100 Hz, 4000 Hz
External dimensions	Width 530x Height 1000x Depth 437 mm
Weight	46 kg (With Net)