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Deal.ai › KFFKFF › 8 Car Subwoofers
KFFKFF
KFFKFF 8" 800W Undercarriage Vehicle Subwoofer

KFFKFF 8" 800W Undercarriage Vehicle Subwoofer

5(1 rating)

Best price now

$70.99at WalmartChecked Nov 9

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Price facts

  • Last seen at $70.99 at Walmart on Nov 9.

Our take on the KFFKFF 8" 800W Undercarriage Vehicle Subwoofer

The KFFKFF 8" is an under-seat powered subwoofer meant to add bass to a factory or aftermarket car stereo without taking up trunk space. Its slim 3.0" cabinet fits under most seats, and it accepts both high-level speaker inputs and low-level RCA signals, so it can tap a factory head unit or an aftermarket one. The 800W figure is peak output, not RMS, and the 50-150 Hz range is narrow even for an 8-inch sub. It suits drivers who want fuller low end in a small cabin or a tight install, not someone chasing deep sub-bass or high output.

Best forDrivers who want more bass without losing trunk spaceSmall cars, trucks and RVs with limited mounting roomFactory head units with no subwoofer output
Pros
  • Slim 3.0" cabinet fits under most seats
  • High-level and RCA inputs cover factory and aftermarket radios
  • Built-in amplifier, so no separate amp to mount
  • Rated 50-150 Hz for music bass rather than subsonic rumble
  • Fixed support feet lift the cabinet to reduce chassis resonance
Cons
  • 800W is peak, not RMS; real continuous power is far lower
  • 50-150 Hz range rolls off before true sub-bass
  • No subsonic filter or detailed tuning controls listed
  • Bass output is modest for an 8-inch driver in a sealed slim box

KFFKFF 8" 800W Undercarriage Vehicle Subwoofer prices at every store

  • WalmartNew

    In stock

    $70.99Checked Nov 9
    Visit Walmart

About the KFFKFF 8" 800W Undercarriage Vehicle Subwoofer

This is an 8-inch under-seat car subwoofer with a slim 3.0-inch profile, built to fit under most car seats. It has a maximum output of 800 W and accepts both high-level and low-level input.

A fixed support design raises the subwoofer off the floor to reduce resonance with the car's chassis. The frequency response is 50-150 Hz. It works in cars, SUVs, trucks and RVs.

It connects with the included RCA audio cable or high-level input cable. The subwoofer turns on automatically when it detects an input signal, and a button on the control panel also activates it. The package includes a user manual, cables and mounting hardware.

Model
YL-813
Rated voltage
DC 12 V
Rated RMS power
400 W
Peak power
800 W
Frequency range
50-150 Hz
Signal-to-noise
> 90%
Speaker size
8 in / 203 mm
Inputs
High-level and low-level (RCA)
Control
Wired remote control
Materials
Aluminum alloy, magnet
Weight
8.6 lbs / 3.9 kg
Dimensions
12.7 x 9.3 x 3.0 in / 322 x 235 x 75 mm
Compatibility
Cars, SUVs, trucks, RVs
In the box
1 x subwoofer, 1 x DC power cord, 1 x fuse, 1 x GND cable, 1 x RCA audio cable, 1 x high to low level converter, 1 x high level input cable, 1 x ACC device connection wire, 1 x volume controller, 4 x

Specifications

color
MulticolorSource
size
8"Source

Questions and answers

Does it need a separate amplifier?
No. It is a powered subwoofer with a built-in amp, so you run power, ground and a signal to it and it plays. You do not need to buy or mount an external amp.
Will it work with my factory stereo?
Yes, if your radio has speaker-level outputs. The high-level inputs let you tap the factory speaker wires without replacing the head unit. Cars with no accessible speaker wiring need an additional line-out converter.
How much real power does it make?
The 800W rating is peak. Continuous RMS power is much lower, which is typical for slim under-seat subs. Expect a noticeable bass boost, not competition-level output.
What is the frequency response?
50-150 Hz. It covers the upper bass that gives kick drums and basslines punch, but it will not reproduce the deep 20-40 Hz notes a larger ported subwoofer can.
Will it fit under my seat?
The cabinet is 3.0 inches tall, which fits under most seats. Measure the clearance under your seat before buying, since power seat mechanisms and vents can reduce it.
What comes in the box?
The subwoofer, mounting hardware and an RCA audio cable for the low-level input. You supply the power wiring and fuse for the amplifier.
Where is the KFFKFF 8" 800W Undercarriage Vehicle Subwoofer cheapest?
At Walmart, for $70.99, as of our latest check.
What do buyers say about the KFFKFF 8" 800W Undercarriage Vehicle Subwoofer?
Rated 5 out of 5 from 1 ratings.

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