In 1989, battery performance and vibration-resistant construction were improved. The stable structure has been enhanced to withstand everyday use.
D-T20
The D-T20 is a portable CD player with a built-in AM/FM tuner. The tuner is integrated into the main unit and controlled using the same systems as CD playback. The headphone cable is used as an antenna. It supports both CD playback and radio reception, allowing switching between audio sources. Playback is limited to that of a standard CD player, and it is designed as a multi-function device.
D-22
The D-22 is a compact portable CD player built on the same platform. It features a slim chassis and a standard transport mechanism, supporting basic CD playback. While it lacks vibration damping, its design prioritizes mechanical stability and power efficiency. The controls are simplified, making it suitable for everyday use.
D-90
The D-90 is a portable CD player with an enhanced exterior and audio output system. While maintaining the basic CD playback mechanism, the chassis structure and finish are of higher quality. Playback remains within the range of a standard CD player and it does not have vibration damping. Its configuration is among the higher-end models of the same period, differentiated by its exterior and output system.
D-250
The D-250 is a higher-end portable CD player with enhanced exterior quality and included accessories. The basic transport mechanism and playback are the same as other models in the series, but the exterior finish and accessory configuration have been expanded. Playback remains within the range of a standard CD player, and it does not have vibration damping. It is positioned as a higher-end model, differentiated by its exterior and included features.
D-350
The D-350 is a portable CD player with expanded control capabilities. It features direct track selection via a numeric keypad, a large display, and support for a wired remote control, improving operation and display. Playback remains within the range of a standard CD player, and it does not have vibration damping. Its configuration prioritizes usability for portable use.
D-Z555
The D-Z555 is a high-end portable CD player designed for high-quality sound reproduction. It features a dual DAC configuration, oversampling processing, a high-quality output circuit, and a wired remote control, improving audio output. While battery-powered, it uses an audio processing configuration close to that of a stationary unit. Playback is limited to that of a standard CD player, and it does not have vibration damping. It is a high-end model that prioritizes sound quality.
D-800K
The D-800K is a portable CD player designed for in-car use. It features a basic CD playback mechanism and is configured for connection to a vehicle power supply and fixed installation. External audio equipment can be connected via line output or a cassette adapter. While it supports battery operation, it is primarily intended for use in a vehicle environment. Its vibration resistance does not match that of dedicated in-car units, and it is adapted for in-car use as a portable device.
D-810
The D-810 is a portable CD player with a standard configuration. The transport mechanism and playback system follow typical designs of the time, and the power system supports multiple supply methods. Playback is limited to that of a standard CD player, and it does not have vibration damping. Its configuration is based on stable specifications, making it suitable for everyday use.
By 1989, portable CDs had reached a design suitable for general use. At the same time, the constraints of the device structure became clear.
