Expect anywhere from 2 GB to 15 GB of hard drive space depending on the sample rate (16-bit vs 24-bit) and the depth of the multi-sampling. Installation Steps
Exploring the Yamaha PSR-S900 Kontakt Library: What You Need to Know yamaha psr s900 kontakt free download 2021
Several developers offer sampled versions of the PSR-S900, often referred to in "free download" contexts or available as affordable premium packs. KievSamples — Yamaha PSR-S900 for Kontakt Expect anywhere from 2 GB to 15 GB