The post in this thread by Mark_H I think explains the confusion.

https://www.meridianunplugged.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=79018#Post79018

The whole reason for this LFE offset is for increasing SPL Level of the sub without clipping (probably with in a 16bit word).

The ONLY thing that SHOULD really be reboosting the the LFE by 10db is the ANALOG amp !!

I think internally Meridian has more range in the digital domain and plays some games to do in the digital domain. But technically it's the sub that should be boosted 10db. I assume test tone for a pure LFE sub is -10db so that it's effectively 10db high.

What Meridian does when you have no sub who knows.

It sounds wrong to boost it at the input and defeats the whole purpose.

- Fiddler (IMHO)

If you think listening to music is fun, try learning an instrument.
HT: G61RSL, 4x5K, 5.5KHC, 2xSC6000, Transporter, HD621, Philips BDP7501 4K, Tivo, 65" LG OLED 4K C6
Computer: Foobar2000, 5K, Mojo, HiFiMan HE1000 V2