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You can add a dose of potent power to your system, thanks to the special design of the Kenwood Excelon XR-4S amplifier. Its dual power supplies and efficient Class D design let this amp deliver massive amounts of power to your speakers from a compact chassis that'll fit in more places than traditional amps can.
The XR-4S offers impressive versatility when it comes to setting up your system. You can use it in 4-channel mode to drive your front and rear speakers, with 120 watts RMS per channel. You can also set it to bi-amp mode when you're powering a component speaker system, and drive the tweeters with the front channels and the midrange speakers with the rear channels.
Got a sub? You can bridge the rear channels to drive a subwoofer, while the front channels power your full-range speakers. The built-in high- and low-pass filters let you tailor the amp's output so you can dial in the best possible performance for the speakers in your vehicle.
- 4-channel amplifier
- 120 watts RMS x 4 at 4 ohms (150 watts RMS x 4 at 2 ohms)
- 300 watts RMS x 2 bridged output at 4 ohms (4-ohm stable in bridged mode)
- CEA-2006 compliant
- variable high- and low-pass filters (50-200 Hz; 2.5K-10k Hz, 12 dB/octave)
- Class-D amplifier design
- frequency response: 20-20k Hz
- preamp inputs
- fuse rating: 30A x 2
- 4-gauge power and ground leads recommended wiring and hardware not included with amplifier
- 9-1/4"W x 2-1/16"H x 7-9/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
My system has plenty of power. Who needs an amp?
You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.
Kenwood Excelon XR-4S Reviews
Average Customer Review:
Crutchfield Customer Review (What's this?)
Purchased as part of a complete system upgrade for a 1979 MGB. Kenwood BT955HD, Polk MM6501, Polk MM691, Kenwood KSC-SW11 sub woofer. Class D was chosen because they draw less current and run cooler which is a concern in Las Vegas. Exceeds expectations. I love the sound.
Pros: Lower current demand than AB amps. Lower temperatures. Class D in theory are over 90% efficient, Class AB somewhere over 60% efficient, waste is heat.
Cons: It does run hotter than expected. Very warm to the touch BUT NOT painfully hot to the touch like the previous AB amps. Previous amps ( 2 amps, 2X100RMS ) worked fine but were both over 10 years old and it seemed a good time to replace them.
Great amp at a great bargain!
Crutchfield Customer Review (What's this?)
I got this amp for my son's car and it sounds great! I got it as a refurbished product and paid half the cost. I have it running in a 2008 Scion XB running the front channel on the front speakers and the back channel running a JL Audio bass tube. Sounds great!
Pros: Great size and power! Takes up less space.
Cons: None so far
I recently upgraded the audio system in my 2007 Dodge Ram MegaCab and purchased this amp after having it recommended to me by a friend who loves his tunes. The first amp I used did not meet my needs or expectations.
I power a Hertz HSK-165 2-way component speaker system for the front stage. The rear door speakers are Alpine SPR 60's that are powered by the head unit for rear fill. To top it off, I have an older Focal 33A sub driven by a Blaupunkt amp.
This amp matches up very nicely with the HSK's. The soundstage is wall to wall and up in front. The frequency response and tonal quality of the HSK's really shine with this amp. There is no distortion at higher volumes and the sound reproduction is crisp, clear and clean.
While this amp is not necessarily top of the line equipment for the audiophile, I would definitely recommend this amp to anyone who wants to get the best out of their system, especially if you have upgraded to a nice set of component speakers.
Nice power in a small package!
Crutchfield Customer Review (What's this?)
Does what it's supposed to do. Amplifies the sound without any discernable coloration. Crossovers work well. Way more efficient than my previous class A/B amp. Tiny, so it's easy to hide away. Can't really say anything negative about it!
Great Amplifier/Little Money
Crutchfield Customer Review (What's this?)
I Purchased this amplifier a couple of weeks ago as a refurbished unit. I had some reservations about buying a refurbished unit but the price is really great and you have a 90 day period to shake out problems. The Amp works great in my 2009 Chevrolet 3500 crew cab. I mounted the Amp along with another Amp for subs along the back wall of the truck cab. The hardest part there is removing the back seat, (a two person job). I also replaced all of the door speakers with high quality alpine componet speakers. I run the amp through the factory stereo with a clean sweep prosesser, There is no compairison between the new stereo set up vs. the factory system. Take then time to get your amps adjusted properly for clean sound. Once you reinstall the back seat, your access to the amps goes away! I am really happy with the set up!
Ignore Negative Comments
Given that I had a full JL Audio setup in my previous vehicle, I had something to compare this setup with.
Before purchasing, I read numerous reviews and had mixed feelings about these Kenwood digital amps (XR-1S for bass) but I got a great deal through another distributor so I took the plunge.
Speaker selection for the XR-4S is a pair of Hertz HSK165 Comps up front (wow!) and my old JL XR650 Coax's rear (and yes, they're struggling to keep up).
Speaker selection for the XR-1S is a pair of JL 10W1v2's.
Pros: *These amps produce a lot of clean power. *Bi-Amp connection (A&B), great feature for independent tweaking. *VIF (XR-1S only), another great feature. *Bass (XR-1S) is tight and punchy *Small footprint.
Cons: *Pricey *Adjustment settings are very sensitive. *They get hot. *Bass Boost on XR-1S (accessory pt # KCA-WR10 is nearly insignificant. (these are all small issues)
The results thus far have been quite satisfying. Sure, they're not my old JL Audio system BUT they are far more than what I initially expected!
Ultimately I didn't give 'em 5 stars because sound quality just slightly diminishes when operating at peak output, HOWEVER THIS MAY BE DUE TO MY OLD, TIRED JL COAX's IN THE REAR (I'll change 'em out in the future and post updated results).
*Side Notes: *Sound deadening material and high quality cables (StreetWires O/F) were used throughout, including battery grounding cable upgrade (as suggested by other reviewer), enhancing sound quality significantly.
great amp if you do 2 things
I had this amp professionally installed and was not happy with it until i tweaked it.
controls are easy to access and adjust. Just remember to follow the manufacturers installation notes. Set the input to match the maximum preamp output voltage of the head unit (do not set the input "by ear" as many professionals will attempt).
Next, upgrade the ground wire from the battery to the grounding point on the vehicle. This changed the amp from an ok sounding amp to a great sounding amp (another step the professionals felt was unnecessary)
Great Little Amp
This is a great little amp. Period. It is well made, just as nice as the Alpine PDX, and the Pioneer Premier ICE, only this one is even more compact. Sound is extremely clear and spacious, whatever Kenwood did they did it right. The XR-4S does not sound like a class D amplifier at all; no audible distortion to speak of.
Things to like: nice feel, heavy, has a cooling fan, full range class D, simple and easy set up. Things to not like: crossover is not variable full range, it can either be set for highs (bi amp to tweeters) or lows (bi amp to woofers or tri amped to subwoofer), or off for full range sound. Would like a little more control here, but I have some flexiblity through the tuning capabilities of my Alpine head unit, so this is not a problem for me.
The amp has two side vents covered by silver grills for flow through ventilation, on the front side where the crossover and input controls are located is also where the fan is located. The unit runs very cool, so far I have really pushed the amp and have not see the fan kick on or the high temperature light come on.
The amplifier is so small and compact it looks like a toy until you pick it up. It is supposed to weight seven pounds, it makes my old 50 watts x 4 seem like a toy. But this Kenwood if good for 120 watts x 4.
What's in the box?
- 4-Channel Excelon amplifier
- Two 30-amp ATO fuses (installed)
- 4 Self-tapping screws
- Rubber terminal cover
- 4mm Allen wrench
- 2.5mm Allen wrench
- Instruction Manual (English/ French/ Spanish)
- Warranty Card
Features and Specs
|RMS Power Output (Watts x Channels)||
120 x 4
|Peak Power Output (Watts x Channels)||300 x 4|
|Power at 2 Ohms (Watts x Channels)||150 x 4|
|Bridged Power (Watts x Channels)||300 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||20-20k Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||73 dB|
|Low-Pass Crossover Frequency||50-200Hz/2.5-10kHz|
|Low-Pass Slope (dB/octave)||12 dB/oct|
|High-Pass Crossover Frequency||50-200Hz/2.5-10kHz|
|High-Pass Slope (dB/octave)||12 dB/oct|
|Bass Boost Frequency||N/A|
|Speaker Level Inputs||No|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
CEA 2006 Compliant: The XR-4S's power ratings are measured according to the strict standards dictated by the Consumer Electronics Association (CEA). These standards allow you to accurately compare the rated power output of all CEA 2006-compliant amplifiers. Manufacturers who adhere to the standards can display the CEA 2006 logo on their products and packaging. The amplifier features the following power specifications:
- 4-Ohm RMS Power Rating: 120 watts x 4-channels into 4-ohms, measured from 20-20 kHz, at 14.4 volts, with no more than 1% THD+noise
- Bridged RMS Power Rating: 300 watts x 2-channels into 4-ohms at 1 kHz with 1% THD
- 2-Ohm RMS Power Rating: 150 watts x 4-channels into 2-ohms at 1 kHz with 1% THD
- Max Power Output: 1200 watts (300 watts x 4-channels) Peak
Class D Amplifier: Class D amps are very efficient and their small size offers installation flexibility. Class-D amplifiers overcome the inefficiencies of traditional Class-A or AB amplifiers. Class-D amplifiers transform very little power into heat, so a higher percentage of the power supply is transformed into the load. This results in a very compact amp which needs less input power to produce very high output power.
Dual Power Supply: This design provides one power supply for positive current and one power supply for negative current. The result is a cleaner voltage source, fewer failures due to short circuit, less power loss due to variances in transformer tolerances, and less transformer noise even when the positive and negative loads are unstable.
Cooling Fan: There is a cooling fan and vents on each side of the amplifier to help dissipate heat and ensure cool, reliable operation. Make sure not to block these vents or the fan when you install the amplifier.
Protection circuitry: The XR-4S features protection circuits that will turn the amp off in case of the following events:
- Speaker wire short-circuits
- Speaker output contacts ground
- Amp overheats
- Unit malfunctions and DC is sent to speaker output
Input Sensitivity: The XR-4S features two gain controls, one for each 2-channel section of the amplifier (A and B). The input sensitivity of each is adjustable from 0.2 volts to 5.0 volts.
Input Select: Set the input select to AB when using both line inputs; set to A when using only one set of inputs to feed all four amplifier channels.
Filter Switch: The A and B sections of the amplifier have individual switches to set the crossover to low-pass, off (full range), or high-pass.
Frequency Range: The A and B sections of the amplifier have individual switches to set the crossover frequency range to high (2.5 kHz to 10 kHz) or low (50 Hz to 200 Hz).
Filter Frequency: The continuously variable crossover frequency range changes depending on the setting of the Frequency Range switch; 50 Hz to 200 Hz in the low position, 2.5 kHz to 10 kHz in the high position. The filter frequency is individually adjustable for the A and B sides of the amplifier.
Power And Ground Terminals: The amplifier features Allen head set-screw Power and Ground terminals that will accommodate up to 4 gauge wire. 6 gauge minimum is recommended.
Remote Turn-On Terminal: The remote turn-on is an Allen head set-screw terminal that will accommodate up to 8 gauge wire.
Speaker Terminals: The four speaker terminals are Allen head set-screw terminals that will accommodate up to 8 gauge wire. 12 gauge minimum is recommended.
RCA Inputs: The amplifier features two pair of gold-plated RCA input connections.
Fuse: The amplifier contains two 30-amp fuses.
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.