Pioneer CS-3000A

Commentary

A speaker system that achieves excellent characteristics by incorporating many unique new technologies into individual units and enclosures, and is completed by sufficient listening.

A 30 cm cone type unit is used for the low range.
The cone paper is made of carefully selected materials and newly developed exclusively for the CS-3000A. The center cap is made of the same material as the cone paper, and the strength is increased by providing unevenness on the wave. It can reproduce a strong low sound.
In addition, the cone edge uses a special urethane foam material that is stable against temperature changes, so that it has excellent linearity and low distortion in the low range and low resonance of the edge are suppressed.
In the cone neck part of the center cap, a new mechanism using a special foam of continuous bubbles is adopted, and non-linear distortion due to air flow in the cap is suppressed, and it also serves as a mechanical filter to prevent abnormal noise generated due to concentrated compliance of the neck part.
The damper uses a double damper structure installed symmetrically, and combined with urethane foam edges to improve the linearity and reliability of the suspension.
The voice coil is a short type with edgewise winding of aluminum ribbon wire. It has excellent heat dissipation and improved input resistance due to the synergistic effect of aluminum foil bobbin and thermosetting epoxy adhesive.
The magnet uses a large ferrite magnet with a diameter of 200 mm that is manufactured by a wet process. The center pole is covered with a pure copper cap to suppress the slight distortion caused by the nonlinearity of the magnetic material.
The frame is made of aluminum die-cast so there is no need to worry about resonance.

A 6.5 cm dome type unit with wire suspension system by copper-beryllium alloy wire is adopted for the middle area.
This suspension is a special method in which a dome-shaped diaphragm is indicated at five points through a wire. In order to give the direction of vibration to the wire, while drawing a slight curve in the vibration direction, the wire is molded with a tapered silicon rubber that is thick on the flange side and becomes thinner as it approaches the voice coil side.
The wire suspension eliminates excess sound radiation from the edge, and the clear support position greatly reduces distortion and improves transient characteristics.
The dome part is designed to be relatively large (65 mm φ) to keep the amplitude small and at the same time to reduce IM distortion.
In addition, it uses a large magnet with a diameter of 156 mm and weight of 1.2 kg. In addition, the voice coil is edgewise wound with aluminum ribbon wire, so it has high efficiency despite being a dome type.
The center pole of the magnetic circuit is covered with a pure copper cap in the same way as the woofer to completely suppress the magnetic strain.
The hole in the center of the pole is tapered. The inner surface is covered with a sound absorbing material made of felt to prevent resonance. The rear back chamber is also filled with glass wool to improve sound absorption.

A 2 cm dome type unit is adopted for the high range.
A duralumin dome diaphragm with a diameter of 2 cm and a thickness of 30 μ m has been adopted for the diaphragm to obtain excellent directional characteristics. In addition, a double-structured edge made of foamed urethane has been adopted for the edge part. Since the front surface is a continuous bubble surface, there is no sound radiation from the edge and it is effective in reducing strain. Moreover, since the compliance and internal loss of the edge itself are large, it does not affect vibration.
In addition, the inside of the dome is packed with micron glass, which is rich in sound absorption, and excellent transient characteristics are obtained. In addition, 10 fins are mounted on the front surface to protect the diaphragm and increase the effect of sound diffusion.
The magnetic circuit uses a magnet (magnetic flux density 16,000 gauss) equivalent to the 16 cm PAX-A16 speaker, which realizes excellent transient characteristics and efficiency.

In the network, the impedance rise at the fo of the mid-range and tweeter is compensated by the compensation circuit, and the characteristic of each unit is made flat, and the phase characteristic near the crossover is improved.
The level control can be performed by switching the coil step-down and the compensation resistance simultaneously. The mid-range can be switched in 4 steps by 2 db, and the high-range can be switched in 5 steps by 2 db.

The enclosure is a combination of 25 mm thick rigid particle board and lauan plywood. For internal reinforcement, a flat plate with four small holes is adopted instead of the conventional rod-shaped structure. It plays the role of standing wave prevention as well as front, rear, left, and right reinforcement.
In addition, glass wool of up to 800g is contained inside.
The vibration and baffle surfaces of each unit are made completely flat, and the grill net is also devised to ensure that the reproduction characteristics are not impaired.
The surface has a gorgeous finish of Brazilian rosewood.

Model Rating

Method	3-Way, 3-Speaker, Airtight Type, Bookshelf Type
Units Used	For low band : 30 cm cone type For Middle Area : 6.5 cm Dome Type For high-pass : 2.0 cm dome type
Impedance	8 Ω
Playback frequency band	30 Hz to 20000 Hz
Output sound pressure level	89dB/W/m
Max Input	100W
Crossover frequency	620 Hz, 4000 Hz When using a multi-amplifier system 2-way : 600 Hz to 1000 Hz 3-way : 600 Hz to 1000 Hz, 4000 Hz to 6000 Hz
External dimensions	Width 360x Height 630x Depth 327 mm
Weight	33kg