What is your ambient room spl level?

[ACHiPo]

25db A
34db C
Both via Decibel X on an iPhone

It helps that all the equipment except for the projector is in an adjacent isolated room, and, that the projector is in a well engineered hush box.

46 dB-C
32 dB-A

 

[Armkreuz]

I see some (too) impressive mesurement here.
You have to realize that phone, by default are very off. The apps needs to be calibrated.
My room is in the basement, fully built to be sound proof ( as much as budget and space allows it) in a very quiet neiborhood.

Using REW + UMIK-1, during the day, i can only go as low as:

33db A
40db C

Using my phone, uncalibrated, I was at:
25db A
30db C

Phones, can give an idea of the noise, but the value are to be taken with a (big) grain of salt.