The files contain no information about sample rate or channel number. You can extract them using VGM toolbox but you get headerless RAW files. The waveforms are 16-bit. Some might be compressed (?) or garbage/unused. In VGM toolbox, do the following:
* File count is at offset [ 8 ] and has size [ 4 ] and byte order [ little endian ] * File records begin at offset [ 476 ] and each record has size [ 8 ] * Use file offsets to determine file lengths
Then drag and drop the BKT file(s) onto VGM toolbox. The extracted files are put in a sub folder where the BKT files are.