The 30kHz filter is the best compromise, it's the default in Roon, and what we recommend for most users. The 24kHz filter results in frequency response characteristics that are nearly guaranteed not to offend your PCM gear, but this involves placing a filter fairly near to the limits of human frequency perception. When I convert a DSD to 88.1kHz Flac, find many quantization noise above 30kHz.
I found xld-20181019's DSD filter can't choice IIR filter. Xld is very good for me to convert SACD-ISO to Flac.
