Yamaha NS1000 Monitor Speaker

Based on the basic idea of ​​creating something that will be used as a reference for a long time, this speaker system was developed using Yamaha's unique technology such as beryllium diaphragms.
It was sold for a long period of 23 years from 1974 to 1997, and was used as a monitor speaker on Swedish and Finnish national broadcasting.

A beryllium diaphragm is used for the mid- and high-range diaphragms.
This diaphragm was successfully developed using our unique technical capabilities by applying the electron beam vacuum evaporation method and special alloy technology used in LSI manufacturing technology.Because it is manufactured in a high vacuum, it is finished with rolled plate material. It contains fewer compounds than other products and achieves high purity.
In addition, because it is first converted into an atomic or plasma state and then vapor-deposited, it is possible to manufacture products with deep dome shapes and tangential edges that are difficult to draw.
Furthermore, by applying a special coating approximately 5 microns thick to the beryllium material, which is prone to corrosion, we have succeeded in protecting it from harmful components in the atmosphere.

A 30cm cone type woofer, JA-3058A, is installed in the low range.
The diaphragm uses corrugated cone paper developed from years of experience in materials research. In addition, the edges are made of cloth double-coated with thermosetting resin and resonance-suppressing viscoelastic resin, increasing linearity in response to input signals.
A 156φ ferrite magnet is adopted as the magnetic circuit, and the voice coil is edgewise wound with copper ribbon wire.

The midrange is equipped with JA-0801, an 8.8cm dome-shaped squawker.
Adopts a beryllium diaphragm with a diameter of 68 mm created by Yamaha's original manufacturing method. In addition, the edge uses a double-coated tangential edge impregnated with viscoelastic resin and thermosetting resin, which was the result of research during the development of soft dome shapes such as NS-690. It has excellent shape retention and center retention ability. In addition, the voice coil adopts a large diameter of 66φ and uses edgewise winding of copper ribbon wire to increase efficiency.
This vibration system is designed so that the air pressure behind each part, such as the beryllium diaphragm, voice coil, and edge, is the same. Behind the diaphragm, the center pole is hollowed out and leads to the back cavity, and behind the voice coil, air holes are made in the bottom plate of the magnetic circuit and passed through the back cavity. In addition, behind the edge, air from the edge is released through the air hole in the voice coil bobbin and also in the outer pole.
The magnetic circuit uses a large 156φ magnet, which has a magnetic flux density of 16,000gauss and improves transient characteristics.
A dome shape with a small radius of curvature is used to increase the rigidity of the diaphragm and improve directivity. To this end, we have suppressed the valleys caused by interference that occur in the on-axis characteristics outside the band by using a diffuser, extended the on-axis characteristics to as wide a range as possible, and improved the connection with the tweeter near the crossover frequency. Masu.

A 3.0cm dome shaped tweeter, JA-0513, is installed in the high range.
The diaphragm uses a 23mm lightweight diaphragm weighing less than 0.03g that takes advantage of the characteristics of beryllium material, and uses cloth tangential edges double-coated with viscoelastic resin and thermosetting resin to eliminate unnecessary It suppresses resonance.
The voice coil diameter is 23 mm, and edgewise winding of aluminum wire is directly connected to the beryllium diaphragm, making the entire vibration system lightweight.
In addition, we have suppressed the effects of resonance by making the center pole of the space behind the voice coil tapered and irregularly shaped, and filling it with sound-absorbing urethane, which is a result of research on the tweeter of the NS-690.

In the design of the network section, we not only check the electrical characteristics but also place importance on the basic actual hearing sensation, and decide by repeatedly listening to samples through cut-and-try techniques.
For the woofer circuit, a 1.0φ formal wire is used and a bobbin containing a large-diameter ferrite core is used to reduce direct current resistance and improve input resistance.
Moreover, the attenuator that sets the level of the squawker and tweeter is a large double-wound one with good input resistance characteristics.

The enclosure is a completely sealed bookshelf type 4-sided design with a black finish.
The NS-1000M uses 24mm particle board for the front baffle, 25mm back plate, and 20mm particle board for the side plates, top plate, and bottom plate. In addition, 24mm thick plywood is placed on the back plate above the woofer mounting hole to provide strong reinforcement, providing appropriate reinforcement at various locations.
The finish is a black semi-gloss finish without cross net.

 SPECIFICATIONS