Frequency response and data or spec sheets for widex and phonak S, M and P receivers

[Zebras]

Answered in your other thread about Lumity with the link I provided.

With more closed type domes, how do hearing aids treat sound below 250 Hz and above 8000 Hz?

Phonak Lumity (depending on what receiver you use as it could be less) only process to 8000 Htz so obviously a more closed dome means you can’t use your national hearing. The receivers go as low as <100 Htz.