Informations from SynthMuseum site: Still 12-bit sampling and 8-voice polyphony, the S950 is an upgraded S900 increasing the sampling rate to 48kHz and the internal RAM capacity to 2.25MB (unlike the S900 its stock 750KB RAM was upgradable), and adding such functions as cross-fade looping, and pre-trigger recording. The front panel is identical to the S900
This document contains details of the floppy disk and file formats used by Akai samplers from the S900 to the S6000 including the S1000 and S3000 series.
The Akai X7000 boasts "High quality sound using 12-bit digital sampling technology" with a "built in front loading disk drive for 2.8-inch disks, permitting speedy data file saving and loading so you can create your own sound library...
informations about the AX60, from SynthMuseum site: The Akai AX60 is a 6-voice polyphonic programmable analog synthesizer with a 5-octave, 61-note (C-C) keyboard.