GX250MG (PB)

A 13cm pure magnesium (99.9% purity) HR-shaped diaphragm + UDRT edge is used for the midrange, which covers all the basic bands of music.

Fostex’s outstanding molding technology has realized an HR-shaped diaphragm using pure magnesium, which is extremely difficult to process due to its low elongation, yet has excellent qualities such as light specific gravity, high internal loss, suppleness, thickness, natural reverberation, and high responsiveness and penetrating power unique to metal.

We have created an ideal diaphragm that suppresses the “sharp ringing” and “lingering aftertaste that does not subside” characteristic of metal.

Like the midrange, the tweeter uses a 25mm pure magnesium ridge-dome shaped diaphragm conforming to the G2000a.

By combining this diaphragm with a powerful magnetic circuit that uses a large 90mm-diameter ferrite magnet and an 80mm-diameter boost magnet, the high frequencies of the midrange are connected as if they have been extended, and a holographic sound image emerges realistically in a transparent and wide sound field.

The woofer also uses the same HR-shaped diaphragm as the midrange.

The acoustic effects of the HR shape’s advantages of resonance dispersion and high shape rigidity contribute greatly to the larger woofer diaphragm as well.

The diaphragm has been made as light as possible in pursuit of higher sound pressure and a natural and smooth tonal connection with the midrange.

It embodies sinking into the deep bass, tight bass and full mid-bass range, realizing the best combination with the midrange with its high penetration power.

The material and thickness of each part of the hexahedron are optimally adjusted to disperse resonance while maintaining strength.

The baffle plate, which has the greatest influence on high sound quality, is 36 mm, which is made of two pieces of 18 mm CE plywood (camphor/eucalyptus plywood) with the properties of solid wood developed for the G2000a and re-joined to achieve a natural sound despite its high rigidity.

A foot (made of brass) with a spherical tip to prevent floor damage and a foot plate (made of brass) to securely attach the foot to the baseboard are attached to the four corners of the baseboard, which is machined from a mass of eight re-ply sheets of 9mm MDF.

The foot is screwed to the foot plate and its height can be fine-tuned, so it also has the function of reducing rattling during installation.

In addition, three cast-iron HR-shaped stabilizers are installed to increase the mass, resulting in a low center of gravity for stable installation and sturdy sound reproduction.

A proprietary high sound quality film capacitor, low distortion and low resistance silicon core coil (for WF) and air core coil (for MID/TW) are caulked and connected using OFC φ0.32mm×19 concentric twisted PE coated wires to achieve low loss and high sound quality.