.NKX File

File extension nkx is used for a special encoded archive files called Monoliths. These NKX Monoliths are proprietary files used in Native Instruments programs, such as Kontakt Player.

The nkx file contains both the audio samples and any other additional graphical content.

These .nkx files are different from .nks files in that each archive might have its own encryption key needed to extract the contents. These keys are usually supplied as part of the package containing the archives, but the exact location may vary and is dependent on the host operating system.

In Window the keys may be saved in the registry, in Mac OS X (macOS) probably in application property files. There is no universal and platform-independent way of accessing these.

Files with nkx extension can mainly be found as so called monoliths - encoded archives used in NI programs. Proprietary format.

How to open:

Use Kontakt Player to work with *.nkx files or unnks software to extract the contents of NKX archives.

How to convert:

Looks like there was nice software called unnks that could extract NKX archives, however it is no longer available for download on the developer site.