A change in the frequency response from albums to single releases

[DooD_music]

Plan

Premium

Country

Denmark

Device

MACBook PRO 2022

Samsung s9+

Operating System

iOs, Android

My Question or Issue

Hi there!

I'm writing my bachelor about streaming services methods to normalize audio, and while testing the different platforms, I found an interesting event  happening in my research.

I've been testing Spotify, and analysed the audio with a frequency response analyser, and I see a change in the frequency response happening in album releases compared to single releases.

On albums the top frequencies are rolled of quite harsh at 16.5khz which I assume is due to the encoding process, but the single releases are showing a frequency that goes up to 20k and maybe even more. I would really love to know the reason behind this! Hope you can help me:)

Best regards from Denmark!