to measure eeg signals you need some differential ampiliers (better ones with active guard) .
another important feature of these amplifiers is, that they make shure that you don't electrify yourself 😄
(even in case of one failure) and no, usual DAQ equipment with usual powersupply doesn't have these isolation classes.
Greetings from Germany
Henrik
LV since v3.1
“ground” is a convenient fantasy
'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'