Many sound design blogs offer free, legal sample packs of classic keyboards. Look for open-source multi-samples of Arranger workstations. You can manually import these WAV files into Kontakt's mapping editor to create your own custom instrument patch. How to Import Custom Samples into Kontakt
The Yamaha PSR-S900 is a powerful keyboard workstation that can be used with external libraries and sounds, including those created with Native Instruments' Kontakt software. While I couldn't provide a direct link to a free download of a verified Kontakt library, users can explore reputable sources for purchasing or acquiring Kontakt libraries compatible with the PSR-S900. yamaha psr s900 kontakt free download verified
The iconic Grand Piano, Silver Trumpets, Saxophones, and Acoustic Guitars. Many sound design blogs offer free, legal sample