loudness on SuperUniti

I doubt it very much.  The Muso is a mainstream (if expensive) consumer product.  The Uniti series are still considered Naim's Hi Fi/Audiophile products and, as such, are unlikely to have tone control/loudness features.

But... For example... SuperUniti has watch and radio alarm functio, mu-so no...

anyway, I would think that the loudness function is a matter of DSP, no hardware...

Me too. It is not required at low levels anyway, it has a very balanced presentation at all volumes.

For what it's worth, the Unitiqute 2 has a loudness option.  As suggested, I see it as being intended to enhance low volume listening, rather than to force obnoxious bass at more normal volumes.

Given that as far as I'm aware the Uniti series all use the same firmware, are you sure the SU doesn't have a loudness feature already?

No loudness facility on SU. It's quite a subtle effect on the Qute2, not like other loudness buttons I experienced in my hifi youth!

I seem to remember one of the Naim guys responding on this and saying the qute's loudness setting came from the work done on the Bentley sound system.

I detest its effect on the sound when it's turned on UQ2. My speakers, my room, so YMMV. It might have been useable  if it had been very carefully and subtly implemented in "- , +" tone control way. Yes, Muso has it as well. L "button" turns it into boom box.

I keep loudness "ON" on my Qute2.  I listen at pretty low levels, and seem to prefer it "ON."

Own up Bart - you just like living in the Phil Zone