Where are your prop discs relative to the pilot seat?

SPL PRO is supposed to be the only accurate sound meter according to a few posts on Reddit. I use the built-in one on my Apple Watch for consistency with a bunch of other readings I've taken over the years.

It's quieter in the back, about the same in the cockpit according to my watch but somehow feels quieter subjectively. The previous owner put in soundproofing, I have flown in several 441s and I can't tell the difference. Supposedly the MT props make things a bit quieter but you lose cruise speed and they are very expensive.

There is a spot behind the pilot bulkhead that is a few db louder than the other side. I have no idea why, there's a refreshment center there but not sure why it would matter.

The important test is do passengers prefer headsets - in the 340 they do in the 441 they don't and even when I ask them to put them on so I don't have to constantly be tapped on the shoulder and remove my earcup they won't. Unless they want to hear ATC, in which case they somehow manage to start talking right as our tail number comes on the radio.

That doesn't work. Too much variability in the microphones.

If everyone were to purchase a calibrated microphone, it would be closer.

https://www.amazon.com/MicW-Calibrated- ... g=btalk-20

It's quieter in the back, about the same in the cockpit according to my watch but somehow feels quieter subjectively. The previous owner put in soundproofing, I have flown in several 441s and I can't tell the difference. Supposedly the MT props make things a bit quieter but you lose cruise speed and they are very expensive.

There is a spot behind the pilot bulkhead that is a few db louder than the other side. I have no idea why, there's a refreshment center there but not sure why it would matter.

The important test is do passengers prefer headsets - in the 340 they do in the 441 they don't and even when I ask them to put them on so I don't have to constantly be tapped on the shoulder and remove my earcup they won't. Unless they want to hear ATC, in which case they somehow manage to start talking right as our tail number comes on the radio.

how would you calibrate your meter????
I have two and they do differ more than I thought they should.

Without professional equipment I don't think you can. Any 3rd party iPhone app would need to be calibrated for each phone model since they all have potentially different parts and microphone openings.

I like using the Apple Watch since it's calibrated for that device, if you have one. I suppose it would still vary slightly depending on the wrist it is put on.

I was on a 737 recently that was 55DbA in my seat during cruise. I think there are so many variables it's nearly impossible to say one airframe is quieter than another, at least within the same category. Jets are smoother but even then an airliner I was on recently made a horrible racket during climb, sounded like some plastic or some part of the interior was resonating with the engines.