[open_erv2]

Thank you, this is correct. Using my class 2 sound meter, if I stand in my house in nowhereland cornwall with power shut off to the whole house, it's 38 dBa. 37 dBa is audible in that environment but nearly inaudible in a normal environment where your computer cooling fan is making 45 dBa at 1 meter, etc. 42 dBa is pretty quiet too, my furnace makes 43 dBa at 1 meter from the duct when it turns on. And that 42 dBa is a full 60 cfm, full blast. That's more than twice the airflow of competing units like the blauberg vento. You don't turn it up that high when you are sleeping.

[teekert]

Ok, so that 25 dB fan is a lie then because it can very easily be heard over other noise.

[open_erv2]

You have to look closely at the actual test protocol, which they rarely share. And in reality noise is hard to measure and hard to understand. There is also SPL and SWL, which are not the same. The marketing department has no clue and convert back and forth with approximations, adding or losing decibels, and nobody ever checks or really knows or, usually, cares. We need third party reviewers with actual sound meters or the numbers mfrs give us are practically useless. This is why I am prioritizing selling beta units to people who can actually test the units.