The original D-50 was a popular 61-key synthesizer that came out in 1987. It's set of sounds contributed to the sound of a diverse group of artists like Prince, Sting, Michael Jackson and Enya. The D-05 recreates the same sounds and presets of the original, and includes many of the same hardware layouts, including the D-50's innovative joystick that made it easy to morph between different onboard tones in real time. There are a few modern touches as well, including a 64-step polyphonic sequencer and a built-in arpeggiator that can be used on its own or as a way to edit original presets.

The D-05 runs on USB power or batteries, has a built-in speaker and can be used as an audio/MIDI interface so that you can just plug it into your Mac or PC without extra hardware. It docks in the same velocity-sensitive K-25m keyboard unit that the other Boutique modules use, as well.