When does Loudness activate

With today's DSP (digital signal processing) the drawbacks to sound quality mentioned there can be eliminated and instead of a generic boost the response can be carefully fitted to the curves. While that opens up a lot of promise, it is only a possibility and based on the manufacturer's priorities it may be met or be not much more tha  the old analog generic boost.

Matching the curves to actual speaker volume and not volume control position on non-integrated speakers remains problematic and likely needing user tuning to get it right unless there is an active equalization process available. 

All speculation until / if Sonos decides to release their implementation details. 

Thanks all, I know the idea behind “classic” loudness (not to be confused with EBU R128).

The question was how it is implemented, especially on components without speakers. But as already mentioned, Sonos seems to have concluded that “Boosts certain frequencies” is enough information.

If I get the time and feel like it I will measure myself some day. It’s not that hard using a measurement microphone. 

If you do, please let us know the results!