Japan Only | In the rest of the world it was released as CDJ-500

The CDJ-50 or CDJ-500 as it is also known by has a Loop button in addition to all the features of it's predecessor the CDJ-30.

Successor : Pioneer DJ CDJ-50II

Features

DJ Compact Disc CD Player
Vinyl Turntable Design
Jog Dial for a closer to vinyl feeling when pitch bending
Jog Wheel used for frame-by-frame search en Cue Point selection
Flat-Top Design
Quick Start
Playing Address, a light bar provides a graphic indication of elapsed playing time
Tempo Control, ±10% pitch range
Master Tempo, locks in the music's pitch even when the tempo changes
Power and Eject button safety guards
Fader Start Play / Back Cue Play (Relay Play)
Auto Cue, cues at the first detection of audio in the track
Loop Button

Specifications

Frequency Response: 4-20kHz
Distortion (TDH): <0.0004%
18-bit 8 time oversampling
Signal to Noise Ratio: >106dB
Dynamic Range: >96dB
Distortion (THD): 106dB
Channel Seperation: >98dB
Power : 110V
Power Consumption: 18W
Dimensions (WxDxH): 320 x 362.1 x 98.5 mm
Weight: 4.0 kg