I don't think the mesurement is misleading. That is what the mesurement is. Each person has different tolelance level. Definately, it is not as loud as SP10 for sure, but it is a different type of noise. It is not a high pitch like SP10 but it is a noise from the high speed fan and the PSU cooling.
The noise is difinitely more than S3 x 1. May be a bit more than S3 x 3-4 units. Its not a fair to compare against 1 S3 vs 1 S4. Power consumption between these machines are more than 4x higher.
Members here wanted to know the reading and specifically asked for it, so I powered up my S4 and provided 2 different mesurements. (I did the same with S3 when it first came out.) Not what I think cusotmer shoudl know, but I try to provide what customers want to know.
That decimal reading is from 1 unit, we may try with stack of a few units in a quiet place & will have an amp reading as well.
What I mean is I can give a buyer two machines with identical dba readings. I can make one unbearable SP10 style, and one perfectly fine, but they will have the same reading. It makes the dba reading totally unsuitable for evaluating the quality of the noise generated.
Obviously someone asked for it so give it to them, I'm just giving my take on dba readings. And this is coming from someone who spend 16 hours a day 5m away from an SP10 for 4 months.