: The definitive source for 256kbps AAC files. To ensure you download the M4A version rather than Lossless, you can adjust your Settings > Playback to "High Quality" instead of "Lossless" before downloading. Amazon Music

The search term refers to the high-quality, DRM-free audio standard used by the Apple Music Store and the iTunes app. This format provides a balance of high-fidelity sound and manageable file sizes. Core Technical Definitions

: Started in 2014, Tidal positioned itself as a high-fidelity streaming service, emphasizing superior sound quality compared to other streaming platforms. It offered a catalog of millions of tracks, many of which were available in lossless audio.

Bandcamp is the indie artist’s heaven. When you buy digital music, you can download in multiple formats—including “AAC (256 kbps M4A).”

So an “iTunes Plus AAC M4A” file is a 256 kbps, DRM-free AAC file that sounds virtually indistinguishable from a CD to most human ears.

This is the "new" frontier referenced in the search query.