604H II

About the 604H II

The Altec Lansing 604H Series II is a classic 2-way coaxial loudspeaker system released around 1978. It features a 38 cm (15 inch) low frequency cone driver combined with a horn-type high frequency driver mounted coaxially. The speaker uses Altec's original Mantare Horn design and incorporates the Tangerine radial phase plug technology, which provides consistent dispersion and extended high frequency response. It has an impedance of 8 ohms and a crossover frequency of 1.5 kHz. The speaker is capable of handling 65 watts of input power and delivers a sound pressure level of 103 dB/W/m (New JIS standard). The voice coil diameters are 76 mm for the low frequency driver and 45 mm for the high frequency driver. The unit weighs approximately 17.2 kg (about 38 pounds) and measures roughly 16 inches in diameter and 11 inches deep. The 604H Series II is highly regarded for its natural sound reproduction and is considered a point-source speaker with excellent phase coherence and soundstage capabilities. It is no longer manufactured and is sought after by collectors and audiophiles.