Is there a difference in quality between RATIO=64 and RATIO=80 for the PDM peripheral?

[Anders Andersson]

I'm investigating the PDM peripheral on the nRF52840 and I have not been able to find out what the RATIO configuration bit actually does.

Presumably it controls how aggressive the decimation filter works, but is there a quantified quality difference?

[haakonsh]

From RATIO: 
Selects the ratio between PDM_CLK and output sample rate.

We have not done any measurements with regards to audio quality with respect to each setting, so that's up to you to decide what setting you want to use.