Hi Indigowolf2,
welcome to the Apple (user-to-user) Community!
Re: Need an equaliser for audiobooks
Am no expert in this area, yet your request for help certainly deserves some response.
Re: "I have just wasted 3 hours dwnloading equaliser apps from the App Store and NONE worked!!
They only worked with music or downloads."
Wondering if you checked whether the file format (or streaming source) you’re using is supported by any of the Equaliser apps you chose. The file format(s) supported by each Equaliser app is often found in the app description page on the App Store.
Third-party (non-Apple) webpage claims to review: 5 Best Equaliser Apps for iPhone and iPad (2024)
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Re: HELP I need an equaliser for a 3rd party audiobook app (Audible).
You might want to consider requesting Audible's help / support Team to add an equaliser feature to their app.
Seems many other people would also like this feature, as expressed on the third-party website (link below):
https://www.reddit.com/r/audible/comments/arwfjp/eq_for_audible_app/
You could also check Audible's audio quality trouble-shooting web-page:
Eg: for any tips that may improve your listening experience.
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Re: " i have tried saving the books as files and dropping it in Apple Music - no joy!"
Wondering what happens if you try opening the audio-book / files / in the Books App on your iPad.
or
You might want to consider other audio-book apps besides Audible:
Third-party webpage article: 10 best audiobook apps for your iPad and iPhone
https://ebookfriendly.com/best-ios-audiobook-player-ipad-iphone/
All the best :-)