ALTEC LANSING 620A Monitor
At 62.6 kg, it doesn’t just sit on your stand—it claims it.
Overview
The ALTEC LANSING 620A Monitor is a bookshelf-type speaker system built around one of Altec’s most storied drivers: the 604-8G coaxial unit. While its “bookshelf” classification might suggest modest proportions, the 620A defies that label with dimensions stretching to 1016 mm in height and a weight of 62.6 kg—more suited to a dedicated studio rack than a casual shelf. The system uses a 2-way, single-speaker configuration with a bass reflex enclosure, engineered for professional monitoring applications where clarity and coherence are non-negotiable. According to available documentation, the 620A was already established in the market by 1977, with reports suggesting it had been available for decades prior—implying a presence stretching back to around 1977.
Owners report the 620A was designed as a high-performance monitoring solution, leveraging the coaxial composite structure of the 604-8G driver. This design routes mid and high frequencies through the throat of the low-frequency magnetic circuit, aligning the acoustic centers to minimize phase differences and improve imaging. The result is a speaker that maintains a coherent soundstage even in complex multi-channel environments. The enclosure’s bright oak finish and deep brown mesh grill give it a professional yet warm aesthetic, though its heft and footprint demand serious consideration in placement.
Specifications
| Manufacturer | ALTEC LANSING |
| Product type | Monitor speaker system, bookshelf type |
| Configuration | 2-Way, 1-Speaker, Bass Reflex System, Bookshelf Type |
| Driver | 38 cm Coaxial Type (Altec 604-8G) |
| Magnet | ALNICO magnet |
| Impedance | 8 Ω |
| Frequency response | 20 Hz to 22 kHz |
| Sensitivity | 103 dB (new JIS) |
| Power handling (continuous program) | 45W |
| Crossover frequency | 1.5kHz |
| External dimensions | Width 660 x Height 1016 x Depth 457 mm |
| Weight | 62.6 kg |
| Cabinet volume | 9 cu ft Altec 620A cabinets |
Key Features
38 cm Coaxial Driver with ALNICO Magnet
At the heart of the 620A lies the Altec 604-8G, a 38 cm coaxial driver featuring an ALNICO magnet structure. This magnet type, known for its smooth magnetic field and vintage tonal character, contributes to the driver’s dynamic response and midrange clarity. The coaxial layout integrates the high-frequency horn directly into the center of the woofer, ensuring time-aligned delivery of frequencies. The 604-8G’s lightweight alloy diaphragm and integrated edge are engineered to reduce mass and distortion, enhancing transient response across a wide frequency range.
Multi-Cellular Horn for Coherent Imaging
The mid/high-frequency section employs a specially designed multi-cellular horn mounted on the axis center. This horn structure is intended to match the sound image precisely, reducing diffraction and improving dispersion control. By minimizing phase differences between the front and rear of the diaphragm, the design supports high resolution in monitoring scenarios where accurate stereo or multi-channel imaging is critical.
Bass Reflex Enclosure with Bright Oak Finish
The 620A’s cabinet is a bass-reflex system with an internal volume of 9 cubic feet, tuned to extend low-frequency response down to 20 Hz. The external dimensions reflect a tall, narrow form factor—660 mm wide, 1016 mm high, and 457 mm deep—finished in bright oak with a deep brown mesh grill. While marketed as a bookshelf type, the size and weight suggest it was intended for dedicated stands or studio mounts. The bass reflex port is integrated into the enclosure design, though its exact location is not specified in available documentation.
Pro Version of the 17 Series
According to user reports, the 620A is considered the professional counterpart to the 17 series of Altec speakers. This designation implies a higher build standard, tighter tolerances, and optimized performance for studio use. Owners report the 620A excels as a near-field monitor, with one noting that even with upgraded drivers like the 416-8B, the cabinet maintains its reputation for accurate, uncolored reproduction.
Collectibility & Value
The 620A has developed a quiet but persistent following among vintage audio enthusiasts, particularly those restoring studio monitors or building period-accurate setups. One documented issue is the tendency for capacitors in the crossover network to leak over time. A repair report confirms that replacing a leaking capacitor with a modern MPK unit restored normal operation, suggesting that while the electronics may require maintenance, they are serviceable with standard restoration practices. No current market prices or auction data are available, but the model’s weight, size, and professional pedigree mean it appeals more to specialists than casual collectors.
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