One of the customers is developing the product by applying ADAU1452 to the product.
There are inquiries about Bessel filters in the filter.
However, when we simulate with the filter coefficients provided by SigmaStudio, the signal size is reduced by -5 dB at the cutoff frequency. If you actually apply a filter and measure the signal with the instrument, -5dB will fall.
In general, I know that the -3 dB drop in cutoff frequency in a filter.
Other filters in SigmaStudio fall -3dB at the cutoff frequency.
Is there a reason why only the Bessel filter drops -5dB?