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Kicker 47KEY2004 Key 4-Channel DSP Smart Amplifier, 4x50W

  • Based on 206 reviews
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Availability: Only 2 left in stock, order soon!
Fulfilled by Pro Audio Center (Authorized Dealer)

Arrives Saturday, Aug 15
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Features

  • Dont just make your system louder - make it clearer. Make it better.
  • Press the selector, and the microphone goes to work. The KEY uses a powerful internal computer to deliver dramatic improvements in realism and soundstage.
  • A massive 40-band equalizer improves tonality, and a 24dB crossover re-defines the capabilities of each speaker.
  • The concert quality of your factory stereo is revealed! What would take hours for a professional to achieve happens in a matter of minutes.

Description

Let KEY professionally tune your system – just sit back and enjoy the music. The KEY200.4 Smart Amplifier uses AI-driven DSP to quickly optimize your sound. Press one button for dramatically improved audio. Measuring under 8 inches long and just 2 inches high, KEY amps fit almost anywhere—behind the radio, under a seat, or in the trunk. KEY amplifiers work with nearly all stock and aftermarket radios, including newer vehicles equipped with start-stop systems. KEY Smart Amps deliver powerful sound with up to 500W RMS for subs and 50W per channel for speakers—everything you need to rock your ride. This compact mono amplifier delivers 500W at 1 ohm, 300W at 2 ohms, and 150W at 4 ohms. Slim 1-11/16" height fits tight installs, with 10–160Hz response, variable LP/HP crossovers, >90dB S/N ratio, and high- or low-level input compatibility. This compact 4-channel amplifier delivers 50W x4 at 4 ohms and includes a microphone with Kicker EQ button for easy tuning. Slim 1-11/16" height fits tight spaces, with 20–20kHz response, selectable active crossovers, high-level inputs, and >90dB signal-to-noise ratio. This revolutionary, DSP (digital signal processor)-controlled, line-output converter automatically detects the frequency response and phase of your factory stereo system, and then allows you to integrate into a more fun, modern entertainment setup!

Item dimensions L x W x H: 10.75 x 8.5 x 2.75 inches


Voltage: 12 Volts


Manufacturer: Kicker


Maximum Supply Voltage: 12 Volts


Mounting Type: Surface Mount


Voltage: 12 Volts


Maximum Supply Voltage: 12 Volts


Mounting Type: Surface Mount


Number of Channels: 4


Output Power: 200 Watts


Item Dimensions: 10.75 x 8.5 x 2.75 inches


Specification Met: FCC


Manufacturer: Kicker


Model: 47KEY2004


Brand Name: KICKER


Warranty Description: 1-Year Manufacturer Warranty


Global Trade Identification Number: 74


UPC: 713034013174


Part Number: 47KEY2004


Item Weight: 2.2 Pounds


Included Components: 47KEY2004


Unit Count: 1.0 Count


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Aug 15

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Powerful and accurate sound.
This DSP and amp is amazing! It gives a huge new dimension to your music. It's pretty small, and it's light, so it can fit in a lot of locations. It's very powerful. You won't need another more powerful amp on the side as well. I can only turn up my volume about 1/3 of the way before it gets unsafe (90dB) to listen to. The color coded wires are helpful and easy to follow. ... show more
Reviewed in the United States on February 16, 2026 by Michael Schneider

  • Pure gold!
What an exceptional little amp. The sound quality is phenomenal, the clarity is fantastic! I combined this with Kicker KS series 6x9 components up front and 6.5 coaxial speakers in the rear of my 2019 F150 XLT. I wish I had done this years ago. Only small crux is I ended up needing to run a remote turn on wire as the auto turn on wasn't functioning properly in my truck. One wire and a lot of rerunning wire and it started up with zero issues. I really hope that Kicker expands the Key technology further in the future. It's now a proven concept that can match the performance of most DSP setups but adds the value of being DIY friendly for those of us who prefer to install our own equipment or cannot afford a full DSP setup and the associated installation and tuning costs and or headaches. I'd love to see Kicker offer a higher watt version of this amp. If and when they do, I'll be seriously considering an upgrade. Not to say that this isn't powerful though, I honestly can't crank it all the way up because it's too loud. I love being able to say that! Also it makes all kinds of music better. It truly doesn't matter what you listen to, you will hear instrumentation and vocals that you have never noticed before while listening to your all time favorite songs. ... show more
Reviewed in the United States on March 20, 2023 by C. Hawley

  • Clear and powerful in a small package
Big improvement over stock in 2025 Ford F150. Very clear at higher volume. With upgraded speakers, the system has vastly improved over the factory non B&O system.
Reviewed in the United States on March 15, 2026 by Pmen

  • Nice compact amp.
This is a compact amplifier with great sound stage. I installed this in a 2025 Kia K5 GT. The amp cleared up the sound in my door speakers so I can actually hear the words at a decent volume. I also replaced my stock door speakers with a set of Rockford Fosgate speakers. Great buy.
Reviewed in the United States on January 8, 2026 by Larry B.

  • Very impressive
Used this in a 66 mustang complete build. Made custom pods for the kicks with tweets six inches above. I have a very nice set of 5.25" CT Sounds components that sounded like a dumpster fire smothered in hot fecal matter. I knew that they needed more power than they are getting from the deck so I went looking for a two channel amp to liven them up. Ended up buying this four channel Kicker after reading lots of reviews. I received the amp on time as expected. It was MUCH smaller than it seemed in pictures. Did the install fitting it all inside the glovebox of the mustang and guess what. Still sounded like garbage only louder. Next step was to hook up the microphone and set up the DSP equalizer, time delay and crossover network. I installed the mic on the headrest and ran the pink noise track. Five min later after some wizardry this thing sounds awesome. Flattened out the mids and tweets blending great with the sub after I plugged it back in after the calibration. I could not be happier with the install and the sound. If you make this purchase please take the time to use the DSP. It makes a world of difference. ... show more
Reviewed in the United States on May 2, 2021 by Jayson

  • Worked with 21 Ram base audio.
Wired the key amp directly to my anc wires, used a anc ch01 harness and is plug and play in my 21 Ram DT with base audio. You cut harness, connect high level to amp wires and connect other side to speakers, the anc ch01 is labeled for speaker wires correctly(no guessing) for the Ram, so makes it easy. Then cut the white connector with yellow and black wire, the anc amp in the Ram has 25 amp fuse, this key amp is 20amp. Black wire is ground. I wired it all up in house, went out and plugged in(takes 30 seconds to plug into old connectors that went in and out from the anc amp. So now sound, turn off auto EQ, is boosts the lows and highs and makes highs too bright. I feel like 50 watts per channel should get louder, I listen to it at over 80% of my total volume. Bass tracks sound fantastic, but rock tends to be lower volume(think that is the music streaming I use). I am going to reset it and try a few more times, seems like the clipping light comes on too soon. Might be due to I have jbl 2.3 ohm 6x9s in back and kenwood 6x9+3.5 component set in parellel up front. It is worthwhile to do in the Ram. I found my windshield reflects a odd sound, so I added a circle sticker under 3.5 cover to stop the windshield relection. Update 5-2-26 I wired a kicker kisloc2 at the speaker inputs at the kicker key to run to a a 2k subwoofer mono amp. The key 200.4 best way is to run the fronts in active and back speakers in the Ram off stock stereo. When doing it this way, you pass through the wires coming into anc(with the anc bypass hasrness) and connect direct to the rear speaker wires on harness. Then you switch the key amp to active and wire the front speakers only into the amp, when the switch is on, the wires coming out of the key amp front will now be dash and rear the doors. Takes a little more work with it this way, will have to run new speaker wires from 3.5 speaker in dash to the amp front input. It was hard for me to get correct sound out of the Ram. Infinity and jbl 3.5 sounded odd, hiss sound etc. Kenwood 3.5 that came with the 6x9 woofer in component set sounded off too, but the 6x9 woofers sounds excellent. So I decided to try wideband 3.5 carbon cone neodyme shca 3.5 speakers and love the sound. No seperate tweeter, but hits the highs and not fatigued after listening. Very happy with sound now. The key 200.4 sounds great and with 1400 watts rms sub amp and 2 10 inch audiocontrol spike subs, is great. ... show more
Reviewed in the United States on May 15, 2025 by rotwiler

  • Nice AMP.
Awesome sound.. install in a 2023 Honda Ridgeline, that was the hard part...the Noise canceling device in the Honda was a pain in the butt to find and shut down. I would buy this amp and again.
Reviewed in the United States on January 5, 2026 by Michael Purington

  • Great Product
Great added to a 24 Colorado. Plenty of power for my small truck. Added a NVX shallow sub to fill out the bass. Running the kicker as a front stage.
Reviewed in the United States on June 13, 2026 by rowland thomas anderson

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