Audio / Spectrum Analyzer vs CD Noise Meter

This RTA app supports simultaneous display of "Audio Waveform", as well as the FFT-based "Amplitude Spectrum" (frequency magnitude) and "Spectrogram" (frequency distribution over time), for audio signals input from a microphone. (FFT: Fast Fourier Transform, RTA: Real Time Analyzer) [Features] - Supports simultaneous display of Waveform / Spectrum / Spectrogram - Supports orientation both portrait and landscape - FFT size - Window function - Spectrum average - Spectrum Tilt - Frequency weighting (Flat, dBA, dBC) - The type of expressing the frequency of Spectrum / Spectrogram (Linear, Log) - Displays the peak level and its frequency of the spectrum - Peak Hold (displays the results of holding past peak values ​​of the spectrum) - Octave Analysis (displays the spectrum divided into octave bands) - Generates the audio signal (Sine, Triangle, Squire, Saw) - Generates the noise signal (white noise, pink noise) - Pitch meter display The Pro version offers Ad-Free Viewing and High-Resolution Analysis (FFT size: 16384, 32768, Spectrum Average: 4, 8). [Setting items] 1. Screen structure : Select the display screen configuration. View Num : 1, 2 View Type : - 1 screen : Wave (Waveform) / 1D (Spectrum) / 2D (Spectrogram) - 2 screens : W+1D / W+2D / 1D+2D Layout : Vertical / Horizon 2. Frequency Axis Scale Type : Selectable the type of expressing the X direction (frequency) of Spectrum / Spectrogram. - Linear: Distributed at equal intervals - Log: The intervals increase logarithmically 3-1. FFT size : 1024, 2048, 4096, 8192, 16384, 32768 (* 16384, 32768 is available in the Pro version.) 3-2. Window function : Hanning, Hamming, Blackman, No window 4. Spectrum Average Number of spectrum average for a display of spectrum. 1, 2, 4, 8 (init value: 1) (* 4 and 8 are available in the Pro version.) Higher value will make the spectrum less noisy and more smooth, at the cost of lower time resolution. 5. Spectrum Tilt : Compensates the visual slope of the spectrum around a 1 kHz pivot. -6.0 to +6.0 dB/oct in 0.5 dB/oct steps (0 means no tilt). 6. Frequency Weighting : Selectable frequency weighting. - Flat: No frequency weighting is applied. - dB(A): Frequency response that takes into account human hearing. - dB(C): Relatively flat response. 7. Peak Hold : Displays the results of holding the past maximum values ​​(peak values) of the spectrum. 8. Octave Analysis : Displays the results of classifying the spectrum into octave bands. Division method: - FFT: Spectral display - 1/24, 1/12, 1/6, 1/3, 1 octave: Display divided into octave bands Calc method: - Max: Displays the maximum spectrum value in each band - Average: Displays the average spectrum value in each band 9. Generates the audio signal : Set the audio signal to be generated. - There are 4 types of waveform. (Sine, Triangle, Squire, Saw) - It can set the value of the frequency in 20Hz - 20000Hz. 10. Generates the noise signal : Set the noise signal to be generated. - There are 2 types of noise. (White noise, pink noise) [Other] - Background color: Black, White - WaveForm: Line Color (Green, Yellow, Invert), Line Width (1.0 ~ 6.0 px) - Spectrum: Bar color (Green, Yellow, Color patterns) - Spectrogram: Colormap, Display range (-150 ~ -60 dB), Display time (4 ~ 60 sec), Apply Spectrum Tilt - Bluetooth connection policy selection (disabled, HFP, A2DP). - Scaling of Waveform / Spectrum display in the Y direction (magnification: 0.5 - 2.0). - Scaling of Spectrum / Spectrogram display in the X direction (magnification: 1.0 - 16.0).

A compact and simple noise level meter. The app works with the device's built-in microphone. Once a measurement is started, the resting noise level is measured, and any sound signals exceeding this level are displayed on the screen. The noise level is indicated both on the display at the top and on the graph at the bottom. Depending on the measured signal level, in addition to the numerical values ​​on the display, the display's background color or brightness also changes. The program allows you to customize the range of displayed values ​​and perform calibration. For added convenience, screenshots can be saved to the gallery.