| Composition | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Tuner | has a digital | has a digital |
| CD players | yes | yes |
| Cassette deck | | yes |
| MP3-players | yes | no |
| DVD-player | no | |
| Blu-ray player | no | no |
| Amplifier | yes | yes |
| Equalizer | yes | yes |
| Navigator | no | no |
| TV tuner | no | |
| General characteristics | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Nominal and maximum power | | 4x22 W/4x47 W |
| Maximum power | 4x50 W | |
| Size | 1 DIN | |
| Management changer | CD | CD |
| CD-changer interface is | custom | custom |
| Color | silver | |
| Supported carriers and formats | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Formats | CD Audio, MP3 | CD-Audio |
| Media | CD-R, CD-RW | cassette |
| Display | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Adjust backlight brightness | | yes, automatic |
| Display type | multicolor | multicolor |
| Cassette deck | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Auto tape | | yes |
| Noise reduction | | DolbyB |
| Auto reverse | | yes |
| To search for music on cassette | | yes |
| Skip pause on the tape | | yes |
| Management | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Multicolor lighting | yes | yes |
| Infrared remote | yes | yes |
| Joystick on the steering wheel | no | no |
| Pause when speaking on the phone | yes | yes |
| Memory disk names | yes | yes |
| Interfaces | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Audio input on the front panel | no | |
| Outputs | audio | audio |
| Bluetooth Support | no | |
| Gold-plated connectors | yes | yes |
| Connecting the ISO | | yes |
| Protection | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Detachable panel | yes | yes |
| Tuner | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Support band | FM, MW, LW | FM, MW, LW |
| RDS | RDS RDS PTY | RDS |
| Number of preset FM/AM | 18 / 6 | |
| Additional information | KENWOOD Z 638 | KENWOOD DPX-4020 |
| Adjusting the voice | yes | yes |
| Single-bit DAC architecture | yes | yes |
| ID3 tag support | no | |
| Super-bass | | yes |
| CD-text | yes | yes |
| Resampling audio | 8 | 8 |
| Disabling voices | | yes |
| Tone compensation | yes | yes |
| Dimensions (WxHxD) | 180x50x160 mm | 180x100x160 mm |
| Features | Display 3DFL. Sleep timer (20/40/60 min). Possibility to change the button illumination. Calendar with memory. | Sleep timer (20/40/60 min). Possibility to change the button illumination. Calendar with memory. System of memorizing the audio settings. Playback of CD-R/RW discs. Tape counter. |
