Anatomy of the Alpine SBR-S8-4 enclosed 8" subwoofer

Add some bass, save some space

Alpine’s SBR-S8-4 ported subwoofer gives you the hard-hitting bass your system was missing — without taking up the valuable storage space you need. The slim box makes place­ment easy — it’s only 6-5/8" deep, so you can install it behind the seat in a standard-cab pickup, and in many other places in small vehicles.

This enclosure is tuned by Alpine’s experts to give you impressive bass with minimal power requirements. The high-quality, medium density fiberboard (MDF) enclosure, internally braced to add stiffness and durability, perfectly matches the 8" Type-R subwoofer, guaranteeing maximum punch while maintaining a small profile.

More cone movement means louder, deeper bass

The High-Amplitude Multi-Roll surround (HAMR, patent pending) allows the cone to move much farther forward and back than a typical surround. This pushes more air, for louder, deeper bass. Its unique shape also lets Alpine put a larger cone in the standard-sized frame.

Plays cool, lasts longer

A subwoofer’s voice coil puts out a lot of heat when it plays, which could damage the sub if not taken care of. Alpine’s patented “Radial Vented Voice Coil Heat Sink & Airflow Management System” uses the motion of the sub itself to suck cool air in and force hot air out, extending the life of the sub.

Massive magnets control accuracy

The power to create music that sounds clear and free of distortion depends on the strength and shape of the magnetic field in the sub’s motor assembly. Alpine packs each Type-R sub with a 10-piece segmented magnet made of strontium ferrite that emits a large field, while maintaining a compact profile.

The shape of the pole piece focuses the magnetic field in the voice coil gap, reducing distortion. It also doubles as an air vent used in the cooling system.

A guide for the bass tones

A ported subwoofer enclosure allows sound from the rear of the woofer cone to travel out of the port and join the sound coming from the front, increasing loudness and enriching the tone. A reason ported subs hit so hard and deep is that the air flowing in and out of the port creates an audio effect like that made by blowing across the mouth of a bottle. That tone adds to and strengthens the note the cone plays.

The wraparound port

There’s no rule that says a port has to be straight, and Alpine cleverly made this one wrap around to save space and keep the enclosure compact. The flared port entrance helps prevent audible “huffing” as air goes in and out. The slanted construction of the port exit serves the same purpose.

Fits in and hits hard

The Alpine SBR-S8-4 8" subwoofer will fill your ride with cool bass no matter where you put it. Carpet covering protects the enclosure from nicks and scratches, while a metal grille guards the cone against any other hazards in your car.

Want one? Get yours today. Or give us a call if you have any questions.