I think “The times they are a-changin’…” Perhaps some HA OEM’s haven’t gotten the word that there’s BT and music streaming, which to some is a very important consideration. Humans can actually hear down to about 20 Hz, although I agree at a certain low frequency and volume, you feel it, too. So I think even in speech with “old-fashioned” hearing aids, you might not appreciate James Earl Jones voice or an octavist’s voice in an opera or a cello. All these sounds can hit 65 Hz (Jones’ voice is rumored to be able to reach 50 Hz). Perhaps if hearing aids are only tested and spec’d down to ~100 Hz because of average male and female human voice frequencies, some HA’s just “accidentally” manage to do a better job in the even lower frequencies that we occasionally hear in human voices and can enjoy hearing coming from musical instruments. I think these days that just considering human voice reproduction in designing a HA would be old-fashioned low tech, like making a classic phone receiver that only reproduces 300 to 3400 Hz sound!