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Alpine SWR-1021D subwoofer – professionally boxed/carpeted for sale – £60
Let's get to the point — this precision-crafted Alpine SWR-1021D dual 2-ohm voice coil Type-R subwoofer handles lots of bass power. Sure, it'll provide the incredible accuracy and ultra-clear sound you expect from Alpine's top-of-the-line, dual 2-ohm subs — but it'll shake the ground, too!
That's because a new motor structure and double-stacked magnet structure focuses magnetic energy within the vented pole piece for incredible power handling. The pulp cone has been treated with Kevlar® (the material used in bulletproof vests) for extra rigidity. A 1" Santoprene rubber surround aids in the nearly 3" of peak-to-peak cone travel while guarding against decay that can mar speaker output.
An extended spider landing area provides extra excursion for fuller bass. The dual 2" voice coils are big enough to handle up to 1,000 watts of peak power and let you wire your system for high efficiency or output. The redesigned tinsel leads are woven into the dual progressive Nomex spiders for long-term dependability. An aluminum diecast frame provides a secure, non-resonant housing. The SWR-1021D is designed for use in sealed or ported enclosures.
Details;
Features
Kevlar Reinforced Pulp Cone: This Alpine Type-R subwoofer has a Kevlar reinforced pulp cone. Kevlar adds strength and tear resistance to the woofer cone while maintaining the benefits of a pulp cone design. There is also an oversized inverted dust cap of the same material, which increases rigidity and virtually eliminates distortion at extreme volume levels.
Santoprene Rubber Surround: The high-excursion 1" Santoprene rubber surround is durable and resistant to the elements, resulting in a very reliable performance. The surround is specially designed to resist deformation that is common in most woofers with wide surrounds. This design gives the surround more control over the woofer cone to reduce distortion and possible driver failure.
Dual Progressive Nomex Spiders: This subwoofer has dual progressive Nomex spiders for added stability and mechanical durability. The custom progressive rolls give the woofer a longer, more linear stroke with maximum centering and restoring force. Special edge control design and Nomex construction provide excellent tear resistance, strength and long-term reliability. By integrating the tinsel leads into the top spider, a nearly 3" peak-to-peak excursion can be achieved with a shallow cone design.
Magnetically Optimized Motor Structure: Through Alpine's advanced magnetic circuit design, this woofer offers better sound quality, and a higher sensitivity and power handling capability:
Compound Radius Curve Pole Geometry: This patent-pending design intensifies the magnetic field for higher SPL and lower distortion. The magnetic field is balanced over a wider area for better control at high excursion. Extra Length Extended Pole: The extra long pole piece provides additional surface to capture radiated heat for additional power handling. Extra Thick Top Plate: This keeps more windings in the magnetic gap for better control. Double Stacked Magnets: These provide the powerful magnetic energy and extra depth for high SPL and maximum control. Bumped Back Plate: This "bottomless" design provides extra room for longer cone excursions. Optimally Saturated Pole: This reduces magnetically induced heat by eliminating eddy currents throughout the voice coil stroke, and evens flux distribution to eliminate "hot spots." Cast Aluminum Frame: The woofer is mounted to a custom cast aluminum frame for added strength. This high mass frame also dissipates heat quickly to make it an integral part of the woofer's thermal management system.
Heat Transfer Plate: This subwoofer contains an integrated heat transfer plate that is thermally coupled to the voice coil. This plate pulls heat away from the voice coil and transfers it to the cast aluminum frame, achieving up to 20% additional power handling, and better reliability.
Dual Flare Pole Vent: Another part of the thermal management system is the unique dual flare design of the pole vent. This maximizes the flow of cooler air to the voice coil, and results in better power handling.
Dual Voice Coils: For increased system flexibility, the woofer has two 2-ohm voice coils. When the voice coils are wired in parallel with each other, the woofer presents a 1-ohm mono load. When the voice coils are wired in series with each other, the woofer presents a 4-ohm mono load. In addition, each coil may be connected to a different amplifier channel and each channel will see a 2-ohm load.
Spring Posts: The woofer has two pairs of spring posts which will accept pin connectors and up to 8 gauge bare wire.
Specifications
Power Handling: This woofer has a total RMS power rating of 300 watts and a total peak power rating of 1000 watts. Each voice coil carries an RMS power rating of 150 watts and a peak power rating of 500 watts.
Note: If you are wiring this DVC sub for lower impedance, make sure that your amp is compatible. Most car amplifiers are stable down to 2 ohms in standard mode, or 4 ohms in bridged operation.
Let's get to the point — this precision-crafted Alpine SWR-1021D dual 2-ohm voice coil Type-R subwoofer handles lots of bass power. Sure, it'll provide the incredible accuracy and ultra-clear sound you expect from Alpine's top-of-the-line, dual 2-ohm subs — but it'll shake the ground, too!
That's because a new motor structure and double-stacked magnet structure focuses magnetic energy within the vented pole piece for incredible power handling. The pulp cone has been treated with Kevlar® (the material used in bulletproof vests) for extra rigidity. A 1" Santoprene rubber surround aids in the nearly 3" of peak-to-peak cone travel while guarding against decay that can mar speaker output.
An extended spider landing area provides extra excursion for fuller bass. The dual 2" voice coils are big enough to handle up to 1,000 watts of peak power and let you wire your system for high efficiency or output. The redesigned tinsel leads are woven into the dual progressive Nomex spiders for long-term dependability. An aluminum diecast frame provides a secure, non-resonant housing. The SWR-1021D is designed for use in sealed or ported enclosures.
Details;
- Kevlar®-infused pulp cone
1" Santoprene rubber surround
dual 2-ohm voice coils
frequency response 28-1,000 Hz
power range 100-300 watts RMS (150 watts per coil)
peak power handling 1,000 watts
sensitivity 85 dB
top-mount depth 5-15/16"
sealed box volume: 0.5-0.8 cubic feet
ported box volume: 0.6-1.25 cubic feet
Features
Kevlar Reinforced Pulp Cone: This Alpine Type-R subwoofer has a Kevlar reinforced pulp cone. Kevlar adds strength and tear resistance to the woofer cone while maintaining the benefits of a pulp cone design. There is also an oversized inverted dust cap of the same material, which increases rigidity and virtually eliminates distortion at extreme volume levels.
Santoprene Rubber Surround: The high-excursion 1" Santoprene rubber surround is durable and resistant to the elements, resulting in a very reliable performance. The surround is specially designed to resist deformation that is common in most woofers with wide surrounds. This design gives the surround more control over the woofer cone to reduce distortion and possible driver failure.
Dual Progressive Nomex Spiders: This subwoofer has dual progressive Nomex spiders for added stability and mechanical durability. The custom progressive rolls give the woofer a longer, more linear stroke with maximum centering and restoring force. Special edge control design and Nomex construction provide excellent tear resistance, strength and long-term reliability. By integrating the tinsel leads into the top spider, a nearly 3" peak-to-peak excursion can be achieved with a shallow cone design.
Magnetically Optimized Motor Structure: Through Alpine's advanced magnetic circuit design, this woofer offers better sound quality, and a higher sensitivity and power handling capability:
Compound Radius Curve Pole Geometry: This patent-pending design intensifies the magnetic field for higher SPL and lower distortion. The magnetic field is balanced over a wider area for better control at high excursion. Extra Length Extended Pole: The extra long pole piece provides additional surface to capture radiated heat for additional power handling. Extra Thick Top Plate: This keeps more windings in the magnetic gap for better control. Double Stacked Magnets: These provide the powerful magnetic energy and extra depth for high SPL and maximum control. Bumped Back Plate: This "bottomless" design provides extra room for longer cone excursions. Optimally Saturated Pole: This reduces magnetically induced heat by eliminating eddy currents throughout the voice coil stroke, and evens flux distribution to eliminate "hot spots." Cast Aluminum Frame: The woofer is mounted to a custom cast aluminum frame for added strength. This high mass frame also dissipates heat quickly to make it an integral part of the woofer's thermal management system.
Heat Transfer Plate: This subwoofer contains an integrated heat transfer plate that is thermally coupled to the voice coil. This plate pulls heat away from the voice coil and transfers it to the cast aluminum frame, achieving up to 20% additional power handling, and better reliability.
Dual Flare Pole Vent: Another part of the thermal management system is the unique dual flare design of the pole vent. This maximizes the flow of cooler air to the voice coil, and results in better power handling.
Dual Voice Coils: For increased system flexibility, the woofer has two 2-ohm voice coils. When the voice coils are wired in parallel with each other, the woofer presents a 1-ohm mono load. When the voice coils are wired in series with each other, the woofer presents a 4-ohm mono load. In addition, each coil may be connected to a different amplifier channel and each channel will see a 2-ohm load.
Spring Posts: The woofer has two pairs of spring posts which will accept pin connectors and up to 8 gauge bare wire.
Specifications
Power Handling: This woofer has a total RMS power rating of 300 watts and a total peak power rating of 1000 watts. Each voice coil carries an RMS power rating of 150 watts and a peak power rating of 500 watts.
Note: If you are wiring this DVC sub for lower impedance, make sure that your amp is compatible. Most car amplifiers are stable down to 2 ohms in standard mode, or 4 ohms in bridged operation.
