Sundown Audio - SD-4 Sealed Box Subwoofer 8" Dual 2 Ohm (Open Box)

Description: Sundown Audio - SD-4 Sealed Box Subwoofer 8" Dual 2 Ohm (Open Box) Sundown Audio - SD-4 Sealed Box Subwoofer 8" D2/D4 The SD-4 series is our premier sealed box offering & is the successor to the SD-3. We started off this design knowing that the majority of sealed box applications today face a depth restriction so each SD-4 model was designed to have the lowest depth possible while still maintaining a large window of mechanical cushion (about 2” p-p maximum mechanical travel for all models). We do not consider the SD-4 an “ultra-shallow” but they are as shallow as possible and feature several techniques to reduce the effective depth required.As mentioned above; the SD-4 series effectively requires less depth than other woofers that are more physically shallow. First of all they lack a pole vent, thus, require no room for air venting behind the motor. This allows the motor to be completely flush against the back wall of the enclosure. To allow for efficient air-cooling we added vent channels on the OD of the pole and side-firing gap venting. Secondly the entire SD-4 series features an all-new foam “W” shape surround – this reduces the space required in front of the woofer gasket to about 1” total. So, despite not being an “ultra-shallow” woofer they have an effective total depth requirement of about 2” less than most traditional woofers of an equal depth. The fourth generation series also upgrades to NEO motors to reduce angled depth requirements substantially versus the SD-3 series! The SD-4 series truly is a world-class sound quality woofer with low mounting depth, small box requirements, and a reasonable price. This line features an under-hung motor topology – this means that the voice coil is shorter than the top plate so the amount of winding in the gap doesn’t change at all over the center portion of stroke – in this case featuring a 1” thick top plate and ½” long 8-layer copper voice coil. This allows for 14.5mm linear excursion one-way while maintaining an extremely flat BL curve. The all new “W” surround design and newly tooled spider work together to create a flat “center” compliance curve which quickly turns progressively stiffer past the linear limits of the motor. This was heavily optimized in 3D computer simulations. This makes the SD-4 significantly more mechanically rugged than the previous generation. To top off distortion reduction features the SD-4 features a shorting ring around the bottom of the pole-piece to even out the LE curve. Available in Dual 2 or Dual 4 Ohm Voice Coils Features Xmax = 14.5mm one-way by 70% BL RMS Power = 600-watts (400-watts for the 8” model) Under-Hung low distortion motor topology Solid pole piece with chamfered edges Black Aluminum 2.5” voice coil former for superior heat dissipation (2” for 8” model) High Temperature 8-Layer copper voice coil wire Large aluminum faraday ring (Pole Base OD) Spring Loaded Terminals Stitched-On Tinsel Lead Wires Optimized for small sealed enclosures Computer Optimized Foam “W” Surround High strength cast aluminum frames (8” model features US Patent D691595) Specifications SD-4 8" T/S SPECSSD-4 8″ D2SD-4 8″ D4 RE (Ohms) 4.2018 6.4276 FS (Hz) 35.6841 36.2549 VAS (L) 12.1640 12.8320 Qes 0.5783 0.6561 Qms 5.7988 5.7301 Qts 0.5259 0.5887 Le (mH) 4.4242 6.0746 BL (NA) 13.1700 14.7716 Mms (Grams) 106.4747 97.7789 Cms (uM/N) 186.8295 197.0082 Sens (dB @ 1w/1m) 81.5509 81.4416 Enclosure Specifications SD-4 8" Sealed Enclosure 0.33-0.5 cu ft Ported Enclosure Not Recommended Recommended Tuning N/A Recommended Port Area N/A Displacement 0.07 cu ft Depth 4.6" Outside Diameter 8.70" Cut-Out 7.30" Physical Dimensions Download Enclosure Designs coming soon... Sundown Audio - SD-4 Sealed Box Subwoofer 8" Dual 2 Ohm (Open Box) Sundown Audio - SD-4 Sealed Box Subwoofer 8" D2/D4 The SD-4 series is our premier sealed box offering & is the successor to the SD-3. We started off this design knowing that the majority of sealed box applications today face a depth restriction so each SD-4 model was designed to have the lowest depth possible while still maintaining a large window of mechanical cushion (about 2” p-p maximum mechanical travel for all models). We do not consider the SD-4 an “ultra-shallow” but they are as shallow as possible and feature several techniques to reduce the effective depth required.As mentioned above; the SD-4 series effectively requires less depth than other woofers that are more physically shallow. First of all they lack a pole vent, thus, require no room for air venting behind the motor. This allows the motor to be completely flush against the back wall of the enclosure. To allow for efficient air-cooling we added vent channels on the OD of the pole and side-firing gap venting. Secondly the entire SD-4 series features an all-new foam “W” shape surround – this reduces the space required in front of the woofer gasket to about 1” total. So, despite not being an “ultra-shallow” woofer they have an effective total depth requirement of about 2” less than most traditional woofers of an equal depth. The fourth generation series also upgrades to NEO motors to reduce angled depth requirements substantially versus the SD-3 series! The SD-4 series truly is a world-class sound quality woofer with low mounting depth, small box requirements, and a reasonable price. This line features an under-hung motor topology – this means that the voice coil is shorter than the top plate so the amount of winding in the gap doesn’t change at all over the center portion of stroke – in this case featuring a 1” thick top plate and ½” long 8-layer copper voice coil. This allows for 14.5mm linear excursion one-way while maintaining an extremely flat BL curve. The all new “W” surround design and newly tooled spider work together to create a flat “center” compliance curve which quickly turns progressively stiffer past the linear limits of the motor. This was heavily optimized in 3D computer simulations. This makes the SD-4 significantly more mechanically rugged than the previous generation. To top off distortion reduction features the SD-4 features a shorting ring around the bottom of the pole-piece to even out the LE curve. Available in Dual 2 or Dual 4 Ohm Voice Coils Features Xmax = 14.5mm one-way by 70% BL RMS Power = 600-watts (400-watts for the 8” model) Under-Hung low distortion motor topology Solid pole piece with chamfered edges Black Aluminum 2.5” voice coil former for superior heat dissipation (2” for 8” model) High Temperature 8-Layer copper voice coil wire Large aluminum faraday ring (Pole Base OD) Spring Loaded Terminals Stitched-On Tinsel Lead Wires Optimized for small sealed enclosures Computer Optimized Foam “W” Surround High strength cast aluminum frames (8” model features US Patent D691595) Specifications SD-4 8" T/S SPECSSD-4 8″ D2SD-4 8″ D4 RE (Ohms) 4.2018 6.4276 FS (Hz) 35.6841 36.2549 VAS (L) 12.1640 12.8320 Qes 0.5783 0.6561 Qms 5.7988 5.7301 Qts 0.5259 0.5887 Le (mH) 4.4242 6.0746 BL (NA) 13.1700 14.7716 Mms (Grams) 106.4747 97.7789 Cms (uM/N) 186.8295 197.0082 Sens (dB @ 1w/1m) 81.5509 81.4416 Enclosure Specifications SD-4 8" Sealed Enclosure 0.33-0.5 cu ft Ported Enclosure Not Recommended Recommended Tuning N/A Recommended Port Area N/A Displacement 0.07 cu ft Depth 4.6" Outside Diameter 8.70" Cut-Out 7.30" Physical Dimensions Download Enclosure Designs coming soon... × × × × × × × Buy now and save! Shipping info Click the Shipping & Payments tab above the listing description for more info FREE Shipping Click the Shipping & Payments tab above the listing description for more info! Additional delivery notes PICK UP OPTION Sorry, our items are NOT available for pick-up. PAYMENT Immediate payment is required upon selecting "Buy It Now" or upon checking out through the cart. We accept payment via U.S. PayPal accounts and all Major Credit Cards, Debit Cards & Google Pay. We are legally required to collect sales tax in those states and localities where we maintain a physical presence (nexus). The applicable amount of sales tax charged to an order will be calculated based on the shipment destination's state and local sales tax laws. Thank you for shopping with us on eBay! Additional Information No additional information at this time Ask seller a question You might also like 240 amp S series alternator for Jeep 4.0 Late Billet Black 170 Amp Racing Alternator GM Truck LS Engine Swap S Series 240a Racing alternator for Honda / Acura V6 S Series 240 amp Alt for Rav4 3.5 Contact To contact our Customer Service Team, simply click the button here and our Customer Service team will be happy to assist. Ask seller a question © Alternator Outlet | Mechman High Output Alternators Authorized Dealer. Fast Ship Times, Made in the USA! Shipping & Payments Shipping is FREE for this item Payment Accepted Payment Methods Immediate payment is required upon selecting "Buy It Now" or upon checking out through the cart. We accept payment via U.S. PayPal accounts and all Major Credit Cards, Debit Cards & Google Pay. We are legally required to collect sales tax in those states and localities where we maintain a physical presence (nexus). The applicable amount of sales tax charged to an order will be calculated based on the shipment destination's state and local sales tax laws. Thank you for shopping with us on eBay! Returns Returns are not accepted Buyer will pay for return shipping. eBay integration by

Price: 287.09 USD

Location: Massena, New York

End Time: 2023-12-10T15:15:19.000Z

Shipping Cost: 0 USD