price: 45 GBP platforms: Spectrum 48k
Combination of two interfaces: A standard Kempston Joystick and a AY-Sound output
Kempston is the widest spread joystick standard in Spectrum games. You need a normal Atari/Commodore compatible Joystick.
The AY-Sound is the same soundchip as in the Spectrum 128. So this interface is for Spectrum 48k or clones that have no soundchip. With this interface you can listen to all music for 128k machines or use sound programs like Soundtracker, ProTracker or Sample Tracker etc.
Of course this interface does not give you more memory, so you can play only programs that fit into 48k memory. Most sound programs and demos use only 48k.
The interface simply plugs into the Spectrum's expansion port and has a through connector, so that you could use it with the DivIDE to store the AY music files, for example. You then need to connect some standard PC speakers to its sound out socket to hear the sound and adjust volume.