RdPiano: Recreating the Roland MKS-20 Reverse Engineered from Silicon
Few digital pianos have achieved the iconic status of the Roland MKS-20. Released in 1986, it introduced a groundbreaking approach called Structured/Adaptive Synthesis (SAS), which analyzed hundreds of dynamic levels to recreate the response of real acoustic pianos. For years, its sound defined countless stage and studio performances. Now, thanks to the work of Italian developer Giulio Zausa, this classic has been reborn as a free software instrument.
What Is RdPiano?
RdPiano is a free plugin (VST, AU, and standalone for Windows and macOS) that emulates the legendary Roland MKS-20 and its SAS-based relatives, the RD-1000 and Rhodes MK-80. But what makes it truly special is how it was created. Giulio describes the project as “reverse engineered from silicon”: he decapped the original chips, studied their microscopic images, and reconstructed the sound engine at logic level. This means RdPiano doesn’t rely on samples but faithfully reproduces the original algorithms.
The Technology Behind It
The MKS-20 was powered by custom Roland gate-array chips and a Hitachi HD6303R CPU. These chips generated sound by layering up to ten waveforms per note, achieving a richness that many considered close to additive synthesis. Giulio painstakingly rebuilt this architecture in software, ensuring the same layering behavior and voice handling, with up to 160 voices available in the plugin. Effects such as chorus, tremolo, and EQ are not strictly modeled but can be added with modern plugins, giving today’s creators flexibility without losing authenticity.
Sound Quality and Character
What sets RdPiano apart from most free pianos is its sonic depth. The MKS-20 was known for blending realism with a unique digital character, and RdPiano captures that identity. The sound has been praised as authentic and inspiring, offering everything from lush ballad tones to brighter textures that cut through a mix. It is not a sample pack disguised as an instrument—it is a faithful emulation of the original sound engine.
Workflow and Accessibility
Despite the complexity of the technology inside, RdPiano remains easy to use. It loads quickly, offers straightforward controls, and integrates seamlessly into any DAW setup. Whether you’re sketching ideas, producing full tracks, or scoring cinematic pieces, it delivers the instant gratification that made the MKS-20 so popular decades ago.
Why RdPiano Matters
Many free plugins focus on quantity over quality, but RdPiano shows what can happen when passion and engineering meet. It bridges past and present, allowing creators to rediscover one of the most important digital pianos ever made without the limitations of aging hardware. For anyone curious about vintage digital synthesis—or simply looking for an expressive piano sound—RdPiano is more than a historical curiosity. It’s a usable, inspiring instrument in its own right.
Available in the ONE Instrument® Cloud Add-Ons
One of the strongest advantages of RdPiano is that you don’t need to search for it across the web. It’s already included in the Add-Ons section of the ONE Instrument® Cloud. Instead of juggling separate downloads and plugin folders, you can install and play it directly alongside all your other virtual instruments. Everything stays in one place, organized and ready, transforming the way you browse, load, and create.
RdPiano is more than just another free piano plugin—it’s a faithful recreation of a digital classic, rebuilt from the silicon up. Thanks to its reverse engineering process, authentic sound, and seamless integration in the ONE Instrument® Cloud Add-Ons, it shows how vintage legends can find new life in today’s creative workflows.