Why is the audio quality different on iPhone SE?

Hi, I understand that there is no equalizer on the iPhone that will work on apps. I use Spotify and YouTube to listen to music and, on both of them, I’m having the same problem. I noticed it particularly because I was playing a song with harmonies and I couldn’t hear the bass voice at all. I messed around with the settings in the apps and then I played the same song in YouTube on my iPad and it sounds fabulous. So it’s got to be something wrong with the iPhone (SE 18.1.1) Any ideas? Thank you.

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