SpecificationsAmplifier SectionMax power output 52 watts x 4 at 4 ohmsPower Ad Hoc CEA2006 Standard Power: 17 Watts RMS per channel into 4 Ohms, 4 channels driven from 20 Hz to 20kHz with less than 1% THD+N.Speaker Impedance 4-8 OhmsAMP & General FeatureAutomatic Level Optimizer YesAux-In Yes (Front)DM+ (Codec enhancer) Yes (Gen2.1)EQ EQ7: 7 band EQ with +/- 6 dB adjustment at 63 Hz, 160 Hz, 400 Hz, 1000 Hz, 2.5 kHz, 6.3 kHz and 16kHz.High Pass Filter Selectable on/off at: 50, 60, 80, 100 or 120 Hz.Loudness Dynamic LoudnessLow Pass Filter Selectable on/off at: 50, 60, 80, 100 or 120 Hz.Output Power (4ohm, 1kHz,16V)(W) 52 watts x 4Pre Out (3) Front, Rear and SubRear Bass Enhancer YesSirius/XM Connector YesSub Out YesTEL ATT/Navi ATT YesTime Alignment Custom Yes (Adjustment)Time Alignment Preset YesUSB Yes (Front)Use Quick-BrowZer® feature to find music by artist, album, genre, song or playlist. Jump Mode allows you to fastforward in a category in 10% increments while the ZAPPIN™ feature can play a 6/9/30 second intro clips to helpyou find a specific song.Advanced Sound EngineThe Advanced Sound Engine uses EQ7 equalizer, adjustable LPF/HPF crossovers, Listener Position calibration,DM+ advanced sound restoration, Rear Bass Enhancer, and Dynamic Loudness volume leveler to deliver animpressive listening experience.RCA outputs for external amplifiersWhen you’re ready to expand your system, the CDX-GT660UP offers 2 volt front, rear and subwoofer pre-ampRCA outputs for external amplifiers. Set the built in electronic HPF/LPF crossovers to improve sound quality andreduce system distortion.Automatic Level OptimizerAutomatic Level Optimizer analyzes each track’s playback levels and adjusts output level to optimize transitionsbetween tracks and sources.SensMe™ App Music ChannelsSensMe™ application can organize your music into playlists that perfectly match your mood, scene and location,making it easier to choose the music that fits the moment.Wireless Remote IncludedThe included wireless remote lets you control the basic functions of your CDX-GT660UP while keeping your eyeson the road.Radio Data SystemRadio Data System (RDS) feature displays radio broadcast information such as artist and track information whenlistening to compatible AM/FM stations.