Altec Lansing 418 15-Inch Alnico Woofer

The Altec Lansing 418 is a legendary 15-inch cast-frame woofer produced during the 1960s and 1970s as part of Altec’s revered 400 Series. Revered for its high efficiency, robust construction, and articulate sound, the 418 found widespread use in professional studio monitors, cinema sound systems, and high-fidelity home audio setups. Favored by engineers and audiophiles alike, this driver exemplifies the golden era of American loudspeaker engineering.

Specifications

Parameter	Specification
Model	Altec Lansing 418
Driver Size	15 inches (380 mm)
Frame Type	Cast aluminum
Magnet Type	Alnico V
Voice Coil	2-inch edgewound
Power Handling	40–60W program power
Nominal Impedance	16 ohms
Sensitivity	98 dB (1W/1m)
Frequency Response	40 Hz – 2.5 kHz (typical)
Surround	Cloth roll
Recommended Enclosure	Horn-loaded or sealed (varies by system)
Weight	~18 lbs (8.2 kg)

Historical Context

The Altec Lansing 418 was a key component in the company’s 400 Series lineup, which included complete speaker systems like the iconic A-7 and 604 Duplex. Designed for professional applications, the 418 was engineered to deliver reliable, high-output performance in demanding environments such as recording studios, movie theaters, and live sound reinforcement.

Its Alnico V magnet and 2-inch edgewound voice coil contributed to exceptional efficiency and dynamic range—critical attributes in an era before high-powered amplifiers became commonplace. The 418’s 16-ohm impedance also made it ideal for use in constant-voltage distributed audio systems, commonly used in commercial installations.

Despite being over half a century old, the 418 remains highly regarded for its musicality and build quality. Many vintage audio enthusiasts restore classic cabinets to feature the 418 as a centerpiece, valuing its warm, natural tonal balance.

Sound Signature

The Altec 418 delivers a warm and articulate midrange, with a solid and punchy bass response that belies its age. Its high sensitivity allows it to perform exceptionally well with low-powered tube amplifiers, making it a favorite among vintage audio aficionados.

While it does not extend as deeply into the sub-bass as modern woofers, its performance in the 50–200 Hz range is tight and musical. When paired with a suitable horn or enclosure—such as the Altec 1105 or 1117—it exhibits excellent transient response and dynamic expression. The Alnico magnet contributes to a smooth, organic character that many describe as “alive” or “effortless.”

Maintenance and Restoration Tips

Due to its age, the Altec 418 may require maintenance to restore optimal performance:

Reconing: Over time, the original cloth surround may degrade or lose flexibility. Professional reconing services can restore the driver to like-new condition using period-correct materials.
Magnet Recharging: Alnico magnets can lose strength over decades. Specialized services can re-magnetize the Alnico V assembly to restore full efficiency and output.
Voice Coil Inspection: Check for rubbing or misalignment, especially if the speaker has been stored improperly. A simple tap test and visual inspection can reveal issues.
Cleaning: Use a soft brush and mild cleaner for the frame and cone. Avoid solvents that may damage the cloth surround or cone coating.
Proper Break-In: After restoration, allow for a gentle break-in period (12–24 hours of low-level playback) to recondition the suspension.

Collectibility and Market Value

The Altec Lansing 418 is considered a collectible driver, earning a 7/10 on the collectibility scale. Its appeal lies in its historical significance, build quality, and sonic character. Drivers in original, working condition typically sell for $150–$300 each, with higher prices for NOS (New Old Stock) or professionally restored units.

Enthusiasts often seek out 418s to restore vintage Altec systems or build high-efficiency speaker projects. Their compatibility with classic horn designs ensures continued demand in the vintage audio market.

Conclusion

The Altec Lansing 418 stands as a testament to mid-20th-century American audio engineering. With its powerful Alnico motor, high sensitivity, and enduring sound quality, it remains a sought-after driver for restorations and custom builds. Whether in a studio monitor, theater system, or home hi-fi setup, the 418 continues to deliver a compelling and musical listening experience—over 50 years after its debut.