Accuracy of Smartphone Sound Level Meter Applications

[Bertman]

Hey all, found this online and figured it was worth a share.

http://asa.scitation.org/doi/full/10.1121/1.4865269

The SPLnFFT app had the best agreement, in unweighted SPLs, with a mean difference of 0.07 dB from the actual reference values.

The SoundMeter app had the best agreement, in A-weighted sound levels, with a mean difference of −0.52 dBA from the reference values.

For unweighted sound level measurements, NoiSee, SoundMeter, and SPLnFFT had mean differences within the ±2 dB of the reference measurement.

For A-weighted sound level measurements, Noise Hunter, NoiSee, and SoundMeter had mean differences within ±2 dBA of the reference measurements.

The agreement with the reference sound level measurements shows that these apps may be considered adequate (over our testing range) for certain occupational noise assessments.

The evidence suggests that for A-weighted data, SoundMeter is the app best suited for occupational and general purpose noise measurements.

In addition to having the smallest mean difference for the A-weighted data, SoundMeter had the narrowest distribution of differences, as shown by the box plot.

The apps with differences outside the ±2 dB/2 dBA are considered not to be in good agreement with unweighted and A-weighted measurements.​

 

[Leodavinci]

Great post but what's the best app for Android? Thanks.

 

[Bertman]

Great post but what's the best app for Android? Thanks.

I believe sound meter by Borce Trajkovski was the best android app, but the results show it's not quite as good as the iPhone app. And everyone's phone may be different. Hope this helps

 

[linearb]

Apple devices all use the same hardware. That is, every generation of iPhone is identical. Android is a wide open field with thousands of different hardware configurations, so it's a lot harder to understand how well your device performs in this regard without using a real dB meter for comparison.

I use Sound Meter Professional on Android, on a Nexus 5. From using it side-by-side with a real meter, I know that it's reasonably accurate up to about 75db, and then it starts clipping hard.

 

[Apocalypse77]

Yesterday I was in a room where my grandfather started hammering nails to the wall. Well I have downloaded this one sound meter app and when my grandfather stopped because he started searching for a new nail I opened this app. When he hit the nail it only showed 87 dB. Can this be right? I think it's just BS.

 

[GregCA]

Hitting the nail is probably too spiky to show an "instant reading". dB ratings are computed on a sampling window.
Use the app to measure a baseline for the environment.

 

[TuneOut]

Hitting the nail is probably too spiky to show an "instant reading". dB ratings are computed on a sampling window.
Use the app to measure a baseline for the environment.

What about the ones with Max readings that show the latest peak? I'm using Sound Meter by Melon Soft.

 

[GregCA]

What about the ones with Max readings that show the latest peak? I'm using Sound Meter by Melon Soft.

The peaks are just the recorded max values from the averaging over a given time window. If the time window is small, they can pick up more "instantaneous readings", but if it's bigger then it becomes an average over a longer period of time.
I use "Decibel 10th" on my iPhone and, from the update rate of the UI, it seems the are averaging over maybe 300 ms or so, so the sound would have to be at a loud level for over half a second to be captured in at least one sampling window.
I suspect the spike of a hammer hitting a nail is much smaller than that.

You could record it and analyze the audio with a free software like Audacity. You'll most likely notice the spike in the signal - then you can measure it's "width" and you'll see how long (in milliseconds) that spike accounts for.

 

[Pleasure_Paulie]

I use logSPL made by the guys who make the best, SPLnFFT.

It's the same measurement accuracy, but they made a simplistic cut down version for the general public. Available from the iOS App Store.

 

[mikejohnno]

My meter never goes higher than 80 db. Likely to do with the phone but it's just ridiculous.

 

[Alue]

I find the phone apps to be all over the place, some things it reads louder than my decibel meter, other things it reads much lower. I put my leaf blower up to my phone and my decibel meter and the phone app read 70 something db and the decibel meter read 100db. Other things the phone app will be about 10db higher than the decibel meter.

For impulse sounds, it's really difficult to get an accurate measurement. Sound pressure cannot be measured in an instant, so there is always some averaging. Most decibel meters average over a 1 second sample window. I don't know what window phone apps measure over, but it's probably about the same with even less accuracy.

 

[Bobbie7]

I was looking at the sound-measuring apps for smartphones under this title but I am unsure of which is best. I have a Samsung Galaxy cell phone and am wondering which app is the most accurate for measuring the sound-level in a noisy restaurant?

The posts on this subject are older and I realize there are constantly new apps being listed. Would anyone know which, amongst the many currently featured, is considered the most reliable? Thanks!

Wishing all a pleasant and peaceful day.

 

[Tinker Bell]

I use one called NIOSH SLM by the National Institute for Occupational Safety and Health and EA Lab. I got the recommendation from a TT thread, but I do not recall which member recommended it.

So far I like it better than other ones that I've tried.

 

[Bobbie7]

Thanks @Tinker Bell I'll try it. Have a good day!

 

[Zenyatta]

I ended up buying a proper dB meter and when I compared the results with an Android app, well... the app wasn't anywhere near reality. I would rather not rely on phones.

 

[Jordyn]

What apps do you use and like on iphone that measure noise levels well and accurately? I just downloaded 3 apps and they all have different measurements from 20-45 dB for my very quiet bedroom right now lol.

 

[Zenyatta]

What apps do you use and like on iphone that measure noise levels well and accurately? I just downloaded 3 apps and they all have different measurements from 20-45 dB for my very quiet bedroom right now lol.

Just invest in a real dB meter - they're quite affordable and you won't have to deal with worrying about all this.

 

[Amber]

What apps do you use and like on iphone that measure noise levels well and accurately? I just downloaded 3 apps and they all have different measurements from 20-45 dB for my very quiet bedroom right now lol.

Buy this https://www.amazon.com/Extech-407730-Digital-Sound-40-130dB/dp/B000EWY67W/

 

[Jordyn]

this isn't for work but more for social situations and curiosity. Id feel a little awkward carrying around a dB reader, plus i prob wouldn't remember to. Last night i was in a resto and i think it was exceptionally loud so i popped in my earplugs. Sometimes i'm just curious how loud it really is.