Sound level meter, required on IPad

[Dagwood]

Has anyone tried using an App based sound level meter? If so how successful was it and which one did you use?
I'm using an iPad3 and want to record traffic and aircraft noise levels.
Dagwood

 

[giradman]

Hi Dagwood - never thought of the iPad as a 'sound meter', so did a google search on ipad app for sound levels decibels and got plenty of hits - was amazed! However, my first thought was just 'how accurate' are these apps? Well, I'm not sure but a few of the negative reviews suggests that if you require accurate SPL measurements, then some 'testing' of the app may be needed? Just one quote below as an example of one the the apps reviewed. Let us know your results in using these apps. Dave

Tests poorly *
by DrJDW - I worked with an audio engineer to test this app on both my iPhone 4S and iPad Mini in a sound isolation lab with a professional sound meter and a standard tone generator producing 1kHz sound. We ramped the sound generator from near zero up to 105 dB as measured by the professional equipment, numerous times. This app never budged from a reading between 58 - 70 dB and even then not in a regular way. Adjusting the controls and settings made no difference. It did seem to respond to instantaneous sounds, like a clap, but not much else. I would not rely on this for anything meaningful.
​

​

 

[oberkc]

I don't use my iPad for this, but DO use an android app on my phone. I have seen others using iOS apps, however. I second giradman's concerns. While I have found these types of apps to be consistent (REPEATABLE), at least...useful for COMPARING sound levels...I have serious doubts about relative to the absolute ACCURACY. Placement, quality, and calibration of microphones are all seriously doubtful here, in my mind. If this is important to you, and you have a source of truth (known sound level), some of these apps have the ability to calibrate and align their readings to account for the variables mentioned earlier.

A comparison of my app to those of my friends to a dedicated sound meter can yield results that can vary by several dB. If you require accuracy, be careful here. Still, I find such very useful to measure and set audio system sound levels to ensure consistency from one day to another.

Otherwise, I say pick one that meets your needs and has the features and displays that are important to you. Do you need any form of spectrum analysis? Do you need pink or white noise generation? Do you need instantaneous readout or just peak? Do you need variable frequency range? Do you need different weightings? Peaks? Averages?

Or, do you need a simple peak sound pressure level and don't care about the fancy stuff?

Edit: in response to another response, I can say that I have never seen an app that failed to respond to levels over 75dB. The two that I have used easily display levels as low as 20 and as high as 110 and above (I try to avoid loud sounds, however). My friends iOS app appears to behave just fine in this regard, but he uses an iPod touch. I don't know if the microphone of an iPad is somehow unable to react to the higher pressure levels. Perhaps the experiment quoted by Giradman was the result of the very-limited 1000Hz frequency and a specific shortcoming in the iPhone microphone at that frequency. Aircraft and traffic noise would be much broader in frequency, more like white noise, I expect.