Hi Sir ,
According to Brett's information , we know how 48dB Butterworth and Bessel filter works in SigmaDSP, we also develope a PC control software , which allow our customer to control the machine developed by us , it's similar with Sigmastudio, but our software is unable to program the SigmaDSP. our software have a function similar with the crossover module in Sigmastudio , that it got a frequency response figure , which user can drag it. With the caculation expression inside of FilterMathCalculations.pdf, we make a frequency response figure for Butterworth and Bessel filter under 48dB, but we cannot make a frequency response figure for 48dB Butterworth and Bessel filter .
There is not caculation expression for 48dB Butterworth and Bessel's frequency response in FilterMathCalculations.pdf , that it only got 24db's . We need the caculation expression for 48dB Butterworth and Bessel's frequency reponse.
Please advise ,thanks.