Combining legendary Denon design concepts along with European-engineered acoustical tuning, the D-M37S personal music system is the ideal choice for a compact music center that delivers a superb musical experience. The built-in CD player features precision Burr-Brown audiophile D/A converters, and features CD-R and CD-RW disc playback compatibility, along with MP3 and WMA playback capability. The D-M37S is fully prepared for portable audio players, and features a front panel USB connection port for MP3 players or USB drives. As with many other Denon models, the D-M37S is also equipped with iPod dock connectivity (optional ASD-1R/11R/3N/3W iPod docks). The powerful amplifier section features Denon's simple and straight circuit design philosophy, and includes a mono output for connection to an external subwoofer. The matching compact loudspeakers feature double layer inverted cone woofers and soft dome tweeters with extended high frequency response, and were co-developed with European acoustical engineers.