The StudioLive Series III features an SDHC Card slot for recording up to 34 tracks (Inputs Channels 1-32 plus a Stereo assignable track for the Main Mix, Aux Mixes, etc.).
Since qualifying cards by Speed Class rating alone is not enough to ensure they will reliably record the maximum track count possible on a fresh format, we've decided to qualify a short list of cards that are affordable, and that we know perform well for multi-track recording. See this link for a list of recommended cards.
- SDXC cards (those bigger than 32 gigs) are default formatted exFat, and will NOT work with the mixer unless you reformat them Fat32.
- The SDcard .org formatter will NOT format an SDXC card as Fat32. It only formats to spec, and the spec for SDXC is exFat. Neither will Windows. You would have to use a third party utility or a Mac.
NOTE: because Fat32 is not the spec filesystem for SDXC cards, an SDXC card formatted as Fat32 can't be officially supported, so your mileage may vary.
It's also important to note that the Series III mixer hardware supports SDHC UHS-I. It may be possible to use UHS-II cards with the Series III mixer, but you will not benefit from the additional bus speed of UHS-II. See here for more info on SD Bus Speed.
(Source: SD Association website)
For more information on speed ratings and classes of SD Cards, refer to this great resource page from the SD Association on Speed Classes.