important: if the Analyzer does not show any signal, please make sure that it has access to the built-in microphone here: settings -> privacy -> microphone
The Analyzer is an universal App designed to work smoothly on iPad and iPhone. Due to the different display sizes there’s only one main difference: while the iPad main view provides a frequency and a SPL Meter view on iPhone the SPL Meter view is available only in portrait mode. We integrated an autorotation lock function for the iPhone to prevent unwanted view changes.
The frequency view shows frequency over time graphs. An overview:
For accessing the menu respectively the properties of the graphs there are icons in the upper right corner:
The workspace is the summary of all snapshots and the actual graph. Touch the workspace icon and save the whole workspace (including color settings), export it, change the background color or remove it for clearing the display.
Save & export
Each snapshot and even whole workspaces can be saved in the Analyzers own proprietary data format. All records are listed in the menu under records. They can be loaded, shared via email or iCloud and exported to images (.png) or text files (.csv). When exporting a workspace to a png file all graph and background colors are preserved while the export of a snapshot creates a black on white picture.
Use thecog wheel in the upper right corner to access the menu. Here you can manage your records, change various settings, visit the store or make use of the sophisticated in-app help.
The left column shows your records. If you select a record a preview appears in the right column. It is zoomable like your main view. If you push the load button the graph shows in your main view. You can delete it, export it to .png or .csv files, send it via mail or move it between local storage (on your iDevice) or iCloud if activated. You can open and share .png and .csv files in appropriate Apps like FileBrowser or Dropbox.
If you want your records available on all your devices you can activate iCloud storage. Go to the iDevice settings -> Analyzer and turn iCloud to on. Now you can move your records between local storage and iCloud storage using the export function!
Audio IO settings
The Analyzer uses either the built-in microphone, an audio source attached to the headset input jack or any suitable USB class-compliant audio hardware attached via the dock connector. The iOS automatically detects which audio input and output are used. If the audio IO route changes the Analyzer automatically blends in the current audio route.
You can select input and output routing in this menu.
When a class-compliant USB audio interface is attached the Analyzer will work always on channel 1&2, 3-8 are not accessible at the moment. We tested successfully and can recommend: Apogee’s One, Duet and Quartet, the RME Fireface UCX, the Alesis IO dock and the Midiface Audioface II.
The frequency range defines the maximum range of the frequency (horizontal) axis.
A single band can either show the sum of energies of each FFT point between left and right border of the band (summed energy) or the mean over the whole band. This decision is made with the band filter mode setting. In sum mode a pink noise input shows a horizontal line and a white noise input shows a line with 3dB / octave rise. In average mode a pink noise input shows a 3dB / octave drop and a white noise input shows a horizontal line:
It is possible to view a normalized spectrum. If the normalization is activated, the level in the frequency view is always normalized to full scale.
The dB range defines the maximum range (dB) of the vertical axis. It is of course only available when normalization is deactivated.
The block size defines the length of the analysis interval.
With the reference frequency you define the “middle” of the frequency scale. Very common for measurements is 1000Hz. We added 440Hz also because this is the “musical” reference (A4).
With the window function you can influence the leakage of the FFT. Available are Rectangular, Hamming, Hann, Blackman, Blackman-Harris and Flat Top. For more information on fft & windowing go here.
Here are some properties and usages for the different window functions: