These are easily purchased online. Some websites offer shipping maybe for an additional charge. They also may be available in a music store or second hand on an online auction website.
A JBL subwoofer can be purchased from JBL directly. Another option, which may actually be cheaper, is to purchase one off of Amazon or an auction site such as eBay.
One can purchase a Kicker subwoofer at many electronics retail stores such as Best Buy, Future Shop and Visions Electronic. One can also buy them at online shopping sites.
One might purchase a Kenwood Subwoofer when one goes to stores like Best Buy, Future Shop. One can also shop online on websites like Amazon and eBay for deals.
A 12-inch subwoofer can be purchased online through Amazon. Amazon is always putting products on sale and there would certainly be a 12-inch subwoofer there at a discounted price. Walmart also sells these items.
I'm pretty sure SVS means saves.
Subwoofer speakers are useful in a home stereo or car stereo system for adding bass depth to the musical sound. One can purchase a 12 inch subwoofer speaker typically from auto parts stores, as well as stereo equipment shops. Amazon is another source for purchasing one.
There is one currently available on Amazon for $15.43 which is decreased from $37.99. It is also the cheapest 8 inch subwoofer on there. It's called "Pyramid WH8 200 Watt High Power 8 Ohm".
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Purchase a subwoofer speaker (also known as a component subwoofer). The component subwoofer is the actual speaker you'll be mounting into the enclosure you build. Crutchfield.com is an excellent resource for reviewing and purchasing component subwoofers
A new home theater subwoofer can be purchased electronic store such as Best Buy, Circuit City. Also you can purchased them online through Amazon, Tiger Direct. The price varies from $180 and Up.
You can purchase a JBL Subwoofer online at Musicians Friend. They have several to choose from. They have an 18" Subwoofer JRX1118SP for $899.00 or an 18" Compact Subwoofer JRX1185 for $399.00. You can also purchase a JBL Subwoofer online on the official website of JBL.
The Kicker CVR subwoofer comes in sizes such as 10", 12" and 15". You can purchase these subwoofers online from the official Kicker website online store.