yuhasz01 wrote:stacyodellnyc wrote:Thank you KaiS! I will give your recommendation a try!!! Might you also know where I can download AudioTools for iPhone for free? I searched but couldn't find it...
Download on iPhone app site. Great tool set. Basic modules are free and others you must do in-app purchase.
Great!
• FFT App has a setting called EPPO (see below) that I prefer over the standard FFT, as it maintains same frequency resolution for treble and bass.
Standard FFT (as a matter of principle) has a high relative resolution in treble, but a lower one in the bass.
• If you set 1/3 octave smoothing, you get an easy readable but still detailed display.
• Use of an independent source for Pink Noise makes handling much easier, as you don’t need to make a cable connection to the iPhone that is used as mic/analyser.
If you have a 2nd iDevice, load the app there too, or use any Internet source or a fitting app on your playback system for the Pink Noise.
Here’s an explanation for EPPO, from Audio Tools help files:
Equal Points Per Octave (EPPO). In this mode, a fairly small FFT (512 points) is run, but only the top octave from this FFT is used. So ... we get about 120 data points in the top octave (think of it as 1/120th octave resolution). Then, we decimate and filter to get the sample rate down to 24kHz, and then run another 512 point FFT. So again, we get 1/120th octave resolution. We continue this process right down to the lowest octave. The result is excellent resolution across the frequency spectrum. The cost is that each octave only updates half as quickly as the octave above it, so the low octaves update much more slowly. The upper octaves, however, retain a very quick response.