Iphone 4s Sound DB Meter App

[adam1122]

Does anyone know what the best app is that you can buy for an Iphone 4s that you may be used to read DB readings from a weapon?

I'd like to see the difference between suppressed and non-suppresed. A buddy of mine who works at custom arms shop has an app for his Android phone and says the app he has is pretty close to what his suppresor manufacturer says it will do.

Obviously, whatever apps are out there they will need to read a minimim of 140DB and thats just with the can on.

 

[Mister Ouchie]

Re: Iphone 4s Sound DB Meter App

I doubt that the mic will really be able to handle anything that loud. All you really need to do is measure the relative difference between suppressed and non, and SPL drops off with distance (inverse square law and all that), so just put the iphone farther away, probably any app would do.

 

[physhphude]

Re: Iphone 4s Sound DB Meter App

look at the ultimate ears app. It's free

Maybe not the most accurate, but it seems to give the readings that I expect from different firearms.

Why would it not be able to handle the noise?

 

[Yasherka]

Re: Iphone 4s Sound DB Meter App

Anyone know of a similar app for Android?

 

[adam1122]

Re: Iphone 4s Sound DB Meter App

I'm sure most apps atbleastbformthe iphonemcan handle themnoisemup to a point. Issue I have found is that some or most apps don't register past 140db so shooting unsuppressed you won't be able to get an accurate reading.

I'm pretty certain hat my can reduces the db to around 132-135. I'd just like to see for myself. Especially if some cheap app that works well for 99 cents.

A buddy I mentioned above who uses one on his android phone says his works best by placing the phone with the mic facing the muzzle and placing it flat on the shooting bench near his rear shooting elbow position and it gives him an accurate reading to manufacturer spec within about 1-2dm. He was shooting an m4 with a surefire can.

 

[Ironman675]

Re: Iphone 4s Sound DB Meter App

I use DB master for a fast reference of machine volume at work, any peaks over 100db are graphed but not measured due to the I phone mic being internally compressed with a zero limit of 100db.
my recommendation would be a Teak or Tascam DB meter. either will register and hold peak data to give you accurate results.

 

[adam1122]

Re: Iphone 4s Sound DB Meter App

Thanks for the info. Any idea how much they cost or best place to,buy one either online or at a retail store maybe?

 

[JohnnyC]

Re: Iphone 4s Sound DB Meter App

You're not going to get accurate dB results out of an iPhone app. There's a reason that silencer manufacturers purchase B&K meters that cost several thousand dollars, or digital testing platforms that are equally as expensive.

Here's the testing procedure from Major Malfunction:
"METER, MICROPHONES, CALIBRATOR, SOFTWARE & WEATHER METER used:
-G.R.A.S. 1/4" pressure microphone, Type 40BD - Prepolarised, High-Level
-G.R.A.S. CCP Preamplifier, Type 26CB
-National Instruments NI USB-4432 - DAQ (Data Acquisition) 102.4 kS/s, 24 Bits, +/- 40 V, IEPE
-National Instruments LabVIEW Full with sound a vibration toolkit (running from a MAC BOOK PRO)
-G.R.A.S. Type 42AB Sound Calibrator
-Kestrel 4500NV Weather Meter

SOUND TESTING PROCEDURES:
-Both MICs are calibrated/validated before each test
-The "Muzzle" MIC is placed @ 1 meter from & 90 degrees to the left of the muzzle (as per "mil-spec" testing criteria)
-The "ear" MIC is placed @ the shooter's right ear
-The tip of the distal end of the silencer is "centered" on top of a reference tripod, IOT ensure proper distance is maintained from the muzzle MIC during testing
-All atmospheric conditions are measured automatically and recorded for each test (they have a HUGE impact on the results of the test and can't be ignored)

SOUND TESTING METHODOLOGY:
-Each "test" will comprise ten shots fired at an interval of approximately 3 seconds. The "results" of each test will be the AVERAGE of the ten shots, as recorded "at the muzzle" and "at the shooter's ear".
-For each silencer we'll conduct several "sound tests" over several months, IOT record how the can performs under various atmospheric conditions (temp. and humidity have can have a significant impact on how a suppressor "performs"). This will allow us to provide an accurate performance estimate for each silencer - we'll average all of the test results over time (there won't be any "one hit wonders") and each suppressor will have a "running average"."

Here's the equipment list that one of the dudes over on nfatalk.org uses:
http://nfatalk.org/forum/showthread.php?t=221

As you can see, they are using dedicated setups, and it's for a good reason. iPhones are great, but they're not dedicated testing platforms.