Summary: I purchased a XRONS car stereo, and the sound was very poor. I have a 944 with 10 speakers, so perhaps it overwhelmed the XRONS (though my old Kenwood sounded much much better). I've never purchased a car amp before, so I was not sure what to expect. Sony products have disappointed me lately, but the XM-4S has restored some of my faith in Sony. It was easy to hook up, takes up little space, does not draw a lot of power and stays pretty cool (and looks very cool as well).
Summary: I love this amp! Great power output for an amp of this size. I purchased this amp to fit under the passenger seat of my IS300 and it fit great! Beats the pants off of the factory system. I would definitely recommend this amp to anyone looking to upgrade their factory system!
Summary: Good deal had some heat problems with the amp added some cooling fans and we will see if that helps it will shut down when it gets hot so no damage to the amp maybe shold have had bigger cooling fins
Summary: I have a small car with very little space for car audio equipment. I found the Sony XM-4S unit to be the perfect amplifier for the car. Its small, compact, and does a great job amplifying the signals from the car's standard head unit. Note, I just wanted crisp clear sound in the car so I used two sets of good coaxial speakers in the car without a sub-woofer. The amplifier has been working great so far.
Summary: I bought the Sony XM-4S it was as it was listed in the auction. Features 500 Watts 50 Watts x 4 at 4 ohms = 200 Watts, 60 Watts x 4 at 2 ohms = 240 Watts. Or 50 Watts x 2 at 4 ohms + 120 Watts x 1 = 220 Watts, or 60 x 2 at 60 Watts + 120 Watts x 1 = 240 Watts.