Combination of two interfaces:

A standard Kempston Joystick - Interface and a AY-Sound output. The Kempston Joystick is the widest spreaded 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 tunes for 128k machines or use sound programs like Soundtracker, ProTracker or Sample Tracker etc. There is no original soundchip used, but compatible CPLD reproduction.

Of course this interface does not give you more memory, so you can play only programs that fits into 48k memory. Fortunately 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 can 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!

Y / Yamaha sound generator (chip included) running at exact speed of 1,75 Mhz (new programmable frequency generator from EPSON (SG8002CA+ PHB)
stereo line output ( jack stereo)
2 joystick ports with ativity leds
multifunction switch (RESET, JOY MODE for port 1)
fully passthrough - you can connect any device that uses ZX Edge connector.
Autofire - fully compatible with typical AMIGA/ATARI/C64 joysticks.
Fully compatible with Kempston mouse and others
build upon Atf1504 CPLD
Beeper sound at stereo ouput on both channels
ABC/ACB channels switch

KempAY - Kempston Joystick and AY 3-8910 Sound Interface