CORAL 4A-70

Commentary

A70 series 10 cm cone type full-range speaker unit.

The 4A-70 uses an Alnico magnet for the magnetic circuit, which improves the magnetic flux density and equalizes the magnetic flux distribution to bring out the power of the cone paper.
In addition, there were three variations of impedance.

The cone paper has been given a hardness treatment unique to Coral to improve its mass and elastic modulus. In addition, a dome radiator using super duralumin is mounted in the center of the cone.

The edge uses a corrugation edge coated with a special damping agent.

There was a protector for protecting speakers sold separately.

Model Rating

Type	10 cm cone type full range unit
Nominal impedance	4 Ω, 8 Ω, 16 Ω
Program source input	40W
Lowest resonance frequency	85Hz
Playback frequency band	Fo ~ 20 kHz
Output sound pressure level	90dB/W/m
Magnetic flux density	11,000gauss
Total flux	75,000maxwell
Effective vibration radius (a)	4.45cm
Equivalent mass of vibration system (mo)	2.7g
Qo	0.42
Weight	1.1kg
Sold Separately	Protector AD-4 (1 piece, ¥ 800)