This app does audio amplification of low audible signal and noise cancellation in real-time. The app allows the operator to design custom Ideal Filters such as Lowpass, Highpass, Bandpass and Bandstop filter by drawing on the touch screen. Because of the zoom in/out capabilities, every frequencies can be increased or decreased on the touch screen.
The app reads audio input data from the microphone, then processed the input signal thru your designed filter and output the results thru your headphone or earpiece.
To take full advantage of this App and listen to the output of your filter design, you must plugin in an earpiece or headphone.
*NOTE to customers*
Please informed us (firstname.lastname@example.org) if you have any issues running the App on your phone or you are not completely satisfied. We can issue you a refund. Thanks, VT
Here are the highlighted features:
1. Four displays: Input Frequency, Filter Response, Filter Design and Time-Domain output.
2. Selectable sample rates and FFT size. Max sample rate of 48k and max FFT size of 16384.
3. Zoom in or out for viewing data at high resolutions.
4. Matlab like colormaps.
5. Display 2D graph setting in line or bar chart mode.
6. Records audio data to SD card or socket for playback.
7. Signal conditioning such as averaging or setting data threshold trigger.
8. Crossbar for easy readout.
9. View data in landscape or portrait mode
10. And many more!
Hardware permission required by this App:
1. WRITE_SETTINGS - This is needed to change the display from sleeping.
2. RECORD_AUDIO - Data taken from microphone.
3. INTERNET - This is required for transmitting audio data over a socket.
4. WRITE_EXTERNAL_STORAGE - Save recorded audio data to SD for playback.
This App covers the following topics: spectral analyzer, signal processing, FFT, acoustics, filter and noise cancellation.
If you like this app, checkout our other apps: Waterfall Spectrum Analyzer, iSpectral, iGram, ActivePinger and FastGram.
**** Mini Manual ****
1. Zoom In/Out
The app starts displaying data as soon as you launch it. To zoom in and out, make sure to press the button starting with "Zm" to "Zm On". Once this is selected start dragging the touch screen and release to zooming in. Press the "Back" button to zoom out.
To see readout of cursor, make sure to press the "Bar" button to "Bar On" and start touching the screen.
3. Filter Design
To design your filter on the touch screen, make sure the "Bar On" button is enable. Then touch the "Filter Design" screen and start moving around to increase or decrease frequencies.
4. Playing Filter Output
To see the output of your designed filter, pressed and toggled the audio button to "Audio On".
5. Optimal Signal
Because of different hardware constraints and environmental settings, you may need to adjust your sample rate, FFT size and Signal-to-Noise (S/N) slider bar.
*Note the default setting should be good enough on most phone.