I'm aware of some reasons why you shouldn't be using ceramic caps in an audio path: capacitance change with DC bias, or piezoelectric/microphonic effects.
Normally I would stick to film capacitors, but for the output stage of some preamps, I would like at least a 10uF cap in order to drive 10k inputs at low frequency. I have 2uF film caps in the parts bin, but they're physically large. So I experimented with some cheap ML caps, similar to these:
https://www.aliexpress.com/item/100pcs-lot-Multilayer-ceramic-capacitor-10uF-106-50V-106k/32455168081.htmlYou could easily fit >60 uF in the same footprint as the film caps, so they are worth a second look. In the intended application, I never use half rail biased stages, so there will never be a constant DC bias across the caps (except for inherent DC offsets in the op amps).
I also checked them for monophonic characteristics, but they didn't exhibit anything more than film caps do. This involved a good hit with a plastic rod to register a signal on the scope, but it was the same with film caps, and totally excessive compared with anything they would be subjected to during use.
They do exhibit audible whines when subjected to rapid changes in DC bias, such as charge pump circuits, but these are basically 0-12V square waves applied to the caps several kHz. In the intended applications, the caps would only be subjected to 10's of mV max across them.
Obviously Ill just have to build something up to do further testing, as there's too much external noise on a breadboard. But beyond that, why else aren't they recommended? Has conventional wisdom not kept pace with the advent of large capacitance ceramic caps?