Whilst the HDD Synth is with beta testers I've been working on a daughterboard for it that will add a full IDE hard drive emulated via an RP2350 chip using an SD card for storage

It's designed to also function stand alone, if you'd just like an IDE drive replacement without any of the sound recreation

However if you put them together it's able to tell the HDD Synth detailed information about how it's virtual read/write head is moving across the virtual drive. So it has the ability to replicate some really realistic mechanical HDD sounds in the future!