ALTEC LANSING Milestone 604

Commentary

Speaker system with 604 to 8 k in newly designed enclosure.

The unit is equipped with 604-8K which is a 38 cm coaxial type unit.
The low-frequency unit has a curved cone and corrugation edge made of high-quality corn paper, and a magnetic circuit made of strong magnets, aluminum, flat wire, and voice coils for reliable piston motion.
A horn type unit is used for the high-frequency band. Mounted through the center of the woofer, this unit features a highly rigid aluminum alloy diaphragm with a traditional tangential edge, heat-resistant voice coil and bobbin, and a Tangerine Phase Plug with low distortion and improved phase characteristics at 604 to 8 K.
Aluminum die-cast is used for the frame of the unit.

The biggest difference between the 604-8K and the original model is the shape of the horn. While the conventional unit used a multi-cellular horn, it has been changed to a manta ray Lehorn, which exhibits remarkably improved directivity and phase characteristics over a wide band.

A vented-type enclosure with an internal volume of 150 liters is used.
The enclosure is designed with a small baffle width to eliminate unwanted vibration and is made of 30 mm thick birch laminate.
Also, the exterior is finished with a teak veneer.

An M. F. level controller is located in the rear of the enclosure.
This level control does not change the level of the high-frequency unit. Instead, it gradually increases or decreases the band around the crossover of the woofer and driver units crossed over at 1.6 kHz by up to 10 dB.

Model Rating

Method	2-Way, 1-Speaker, Bass Reflex System, Bookshelf Type
Unit	For All Bands : 38 cm Coaxial Type 2-way (604-8K) For low band : 38 cm cone type High Pass : 2.5 cm Driver + Mantalehorn
Impedance	8 Ω
Playback frequency band	40 Hz to 20 kHz
Crossover frequency	1.6kHz
Sound pressure level	100dB SPL/W/m
Allowable input	75W
External dimensions	Width 465x Height 905x Depth 505 mm
Weight	55kg