Most retro PCs are retrofitted with a solid-state hard drive these days, due to the rarity, unreliability and inconveniences of using a traditional mechanical spinning drive. 

However, that means when using a retro PC you miss out on the full nostalgic experience of hearing the HDD:

• Spin up when you power the system on
• Click and whir as your favourite games load
• Spin down after powering off

The HDD Synth is an ISA expansion card that recreates the sound of a mechanical hard drive for your retro PC

• Sample based recreation of mechanical hard disk drives operating sounds
  • Spin up when PC is turned on
  • Idle hum whilst standing by
  • Access clicks and crackcles
  • Spin down when PC is turned off
• SD card to hold multiple HDD sample packs, to recreate the sound of different mechanical hard disk drives
• Volume control to make it very loud or silent
• Balance to alter the amount of idle to access sounds
• CompactFlash adapter to act as full HDD replacement
• HDD detection via HDD LED

Prototype MKI [Completed] ✅

Initial ISA PCB test

Prototype MKII [Completed] ✅

Adds volume control, ability to change sample pack, spin down

Prototype MKIII [Completed] ✅

Adds ISA based HDD detection, metal back bracket, external status LED, 3.5" drive bay adapter kit, balance (between access and idle sound)

Prototype MKIV [In progress] ▶️

Smaller and more cost effective than the MKIII. Adds a CompactFlash adapter so can act as full HDD replacement. Headless by default, optional controls and OLED screen can be added

Production

Create units for general availability, planned for Q3 2026 initial through a Kickstarter

HDD Synth 1000

The full experience

• SD card with multiple sample packs
• Spin down playback when power is turned off
• True plug and play with no HDD LED cable required)

HDD Synth 500

Cost reduced

• No SD card reader, just a single sample pack
• No spin down
• No ISA based HDD detection, requires connection of HDD LED cable

• Progress updates
  Blog posts about the project
• Vogons thread
  Community discussion
• YouTube playlist
  Development update videos 
• GitHub
  Open source hardware and software

• Peter Bridger, Project Lead
  Hardware/software design
• Mark Angus, Sound Design -
  Creation of audio samples
• Ian (PSYCHROME) Ball, Art Design
  MHDDLA stickers

If you'd like, you can donate to support this project on Ko-Fi 

• Retro Collective (YouTube)
• This Week in Retro (YouTube)
• Hackster (Website)
• TechEBlog (Website)