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Discounted install kit, wiring harness and antenna adapters with most stereos
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RMS Power Handling
The RMS power is the amount of power the speaker requires to operate safely and properly. RMS Power Handling refers to the amount of power a speaker can handle on a continuous basis. We recommend powering your speakers or subwoofer with 80%-120% of its recommended RMS rating. The RMS power handling specification is typically rated per speaker unless otherwise noted.
Peak Power Handling
Peak power handling refers to the amount of power a speaker can handle during a brief musical burst. The RMS power range figure is a much more reliable rating for determining the speaker's power requirements. The Peak power handling specification is typically rated per speaker unless otherwise noted.
Series
Many brands group their products into series or lines of products to help customers know the level of quality (good, better, best for example). You can filter by series and the brand using our guided browsing.
Subwoofer Size
Refers to the diameter of the subwoofer, measured in inches.
Shallow Mount Installation
This means that the subwoofer/speaker is designed to be installed in areas that do not have a lot of space. Shallow mount subwoofers are typically found under a seat or behind the seat in some trucks.

Shallow mount speakers will typically have a mounting depth of 2" or less, while shallow mount subwoofers will typically have a mounting depth of 3" or less.
Top-Mount Depth (Mounting Depth)
The depth when installed on top of the mounting surface. Measured from the bottom of the speaker's magnet to the bottom of the mounting holes on the rim of the speaker.
Voice Coil(s)
Dual voice coil subs have more wiring flexibility than single voice coils subs; however, single voice coil subwoofers provide easier hookup options for wiring multiple subwoofers in parallel or series. You may also run a dual voice coil (DVC) sub in parallel, series, or combination. A quad voice coil has four voice coils and is equal to two dual voice coil subwoofers as far as wiring goes.
Impedance (Per Voice Coil)
The load value (in ohms) that the speakers present to the amplifier per voice coil - the amount of resistance to the current flow. This is a key specification as subs wired in parallel or low impedances can create problems with your amplifier and potentially void all warranties. We encourage you to ask our support department prior to purchase if you do not understand which impedance level will suit your application best.
Subwoofer Design
This is the design of the subwoofer or the opening of the subwoofer enclosure. Each design has it's own benefits, whether it is a square, circle, or oval.

Round/Circle: This is the typical and common subwoofer design. They have a round cone and are a circle in design.

Square: These woofers are able to achieve a greater cone area in a smaller space. Because of the greater surface area, some square subwoofers will be louder than a round subwoofer of the same size.

Minimum Sealed Box Volume
This value indicates the minimum sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
Maximum Sealed Box Volume
This value indicates the maximum sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
Sensitivity
An efficiency or sensitivity rating tells you how effectively a speaker converts power into sound. The higher the number, the more efficient the speaker and the louder it will play with the same input power. An efficient speaker helps you maximize your available power. Most sensitivity ratings measure the speaker's output with 1 watt of input, 1 meter from the speaker. Some speakers' sensitivity is measured with 2.83 volts of input, instead of 1 watt.
  Efficiency (1w/1m) is not an accurate indicator of a subwoofer's output capability and should not be used as a comparison to other speakers or subwoofers to determine which one is "louder".
Main Cone Color
This is the color of the speaker's or subwoofer's cone.
Recommended Enclosure Type
This is the recommended type of enclosure that the subwoofer should be installed into. Some subwoofers are specially designed for particular enclosures.

Sealed: These enclosures completely enclose the air inside the box. These boxes produce a tight bass.

Ported/Vented: These enclosures have a slot of air to escape from the box. The result is a sound that has more "boom".

Bandpass: These are a combination of both sealed and ported enclosures. They can be very efficient, but require tuning for the best response.

Xmax (millimeters)
Typically measured in millimeters, the Xmax value is the measure of a speaker cone's maximum excursion in one direction while maintaining a linear behavior.
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Sundown Audio SML-8 D4 8" (SML8D4) (Open Box, Great)

800W Peak (400W RMS) 8" SML Series Dual 4-ohm Shallow Car Subwoofer (SW-SML8D4)

SW-SML8D4 big
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Sundown Audio SML-8 D4 8" (SML8D4) (Open Box, Great)

800W Peak (400W RMS) 8" SML Series Dual 4-ohm Shallow Car Subwoofer (SW-SML8D4)

• Peak Power: 800 watts
• RMS Power: 400 watts
• Impedance: Dual 4 ohm
• Pressed Paper cone
• Pressed Foam surround
• Mount depth: 3.9"
• Sensitivity: 82.5 dB

10% Off Open Box!
shipping truck icon Free shipping in USA. Provide zip for delivery date.
List price $203.99
-35% $132.99
$119.69 with coupon | Price details

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• Peak Power: 800 watts
• RMS Power: 400 watts
• Impedance: Dual 4 ohm
• Pressed Paper cone
• Pressed Foam surround
• Mount depth: 3.9"
• Sensitivity: 82.5 dB

 
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