I designed a 8th-order filter in Matlab and transform it into the SigmaStudio.In order to get the 8th-order filter I use four 2nd-order filter as follows.

The response of filter get from the Probe have a strange shift campare with the desired response designed in Matlab.The response of magnitude raise up and the phase drop down below 100Hz in sigmastudio.

Matlab

SigmaStudio

Who can tell me the reason of the change in SigmaStudio.Thanks a lot.

It might be rounding issues on the coefficients, going from floating point to fixed point. You should plot your responses with the same scale to see how big the difference actually is; it looks quite exaggerated on the sigma.