Audio SA vs Sound Level & Spectrogram

"Audio SA" is a spectrum analyzer that can capture voiceprints as TFFT images. The created TFFT image can be exported as a high resolution image. (Image size example iPhoneSE3: 4096×4096, iPhoneX: 6144×6144) If you just want to try creating a voiceprint, you don't need to worry about the settings. Just record your voice and run the TFFT to see the voiceprint. "Audio SA" can also be used for FFT-related learning. You can also check changes in important characteristics such as FFT frequency resolution and dynamic range while switching the FFT size and window function. As an additional function, we have implemented a simple waveform generator, so please try it when learning. The simple waveform generator can generate sine waves, square waves, Gaussian white noise, and their combinations. When using TFFT images for machine learning, etc., it will be necessary to give sufficient consideration to the settings. "Audio SA" allows you to set the audio waveform analysis range, FFT size, power spectrum scale, window function, and drawing color. The analysis range of the audio waveform is set by scaling and moving the audio waveform. The displayed range becomes the analysis range. Tap the play button to play only the analysis range, which is convenient for checking. FFT size can be selected from 256,512,1024,2048,4096,8192,16384,32768. (However, you can select from 256, 512, 1024, 2048, and 4096 during recording and playback.) The power spectrum scale can be selected from Linear scale, Log scale, and Mel scale. For Mel scale, you can set the break frequency. The mel scale is close to a linear scale up to the break frequency and close to a log scale after the break frequency. 700Hz, which is the most commonly used frequency, is set as the default value. The window function can be selected from Blackman, Hamming, Hann, Rectangular. It is recommended to choose Blackman when wide dynamic range is required and Hamming when high frequency resolution is required. Roughly speaking, Hann is a trait between Blackman and Hamming. For Rectangular, no special window function is multiplied during FFT transform. The audio data cut out from the audio waveform for the FFT size is used as it is. In addition, the lower limit of the dynamic range when drawing TFFT images can also be set. It's easy to set up, just swipe up and down on the FFT image. The part displayed as the FFT image is drawn as it is in the TFFT image. "Audio SA" consumes tickets to record audio. Tickets can be earned by watching ads. However, if you purchase "Remove Ads" as an in-app purchase, you will be able to record without a ticket. [details] https://app.brain-workout.org/spectrumanalyzer-e/

"Sound Level & Spectrogram" is a sound level meter app for iPhone to easily measure the sound level of noise and music in your living environment. Simply tap the start button to measure sound levels in decibels (dB) and view the real-time variation of the sound level. You can also use the spectrogram feature to visually check the frequency characteristics of the sound source. Furthermore, you can select between frequency weighting correction characteristics and time weighting characteristics, which are essential for standard sound level meters, enabling appropriate sound measurement. Exposure to noise can impact health, potentially causing tinnitus, sleep disorders, stress, cognitive decline and heart disease. These risks have also been highlighted by the World Health Organization (WHO). Understanding noise levels is the first step towards improving your quality of life. Use this app to protect your health and create a comfortable living environment. Features: - Sound level measurement (dB): Leq (equivalent sound level), Min (minimum value), Max (maximum value), Avg (time-averaged equivalent sound level) - Frequency weighting correction characteristics: A (general sound level measurement with auditory correction), C (sound level measurement with almost flatter correction than A correction, e.g. peak evaluation at high volume), Z (flat characteristics without auditory correction, physical sound level measurement) - Time weighting characteristics: Fast=0.125sec, Slow=1.0sec - Time course graph - Spectrogram: 1/3 octave band analysis - Measurement time: 20 sec Applications: - Environmental noise measurement - Architectural acoustics - Live sound check - Installation of audio equipment - Tuning of sound equipment - Device management Example of the noise level situation: - 130 dB: Engine sound of Airplane - 110 dB: Horn of Car - 100 dB: Noise of passing train - 90 dB: In loud factory - 80 dB: In the train, Vacuum cleaner - 70 dB: Noisy office, Noisy Street - 60 dB: Quiet Car, Normal conversation - 50 dB: Quiet office - 40 dB: In the library, Quiet residential area - 30 dB: Outskirts of midnight, Whisper - 20 dB: Sounds of rubbing leaves Note: - Spectrogram is a tool to analyze the frequency spectrum of sound, with time on the horizontal axis, frequency on the vertical axis, and the strength of the signal represented by colors, and is used for acoustic analysis, voiceprint identification, etc. - This app is adjusted the reference value for iPhone. However, the built-in microphone of your iPhone is likely to have a non-uniform gain. Therefore, exact measurements are not guaranteed. - The standard noise measurement range is 30-130 dBA, and the measured value (Leq) is about 30 dBA in a quiet room of the household. Due to the presence of background noise, noise levels are never measured at 0dBA even in very quiet environments. In a typical anechoic room, the noise level is around 5-15 dBA. - At the initial startup after installing the app, the iOS system asks for permission to access the built-in microphone. In this case, you need to enable access to the microphone. If you have not enabled this setting, this app cannot work by privacy restrictions of the iOS system. Please enable the access permission on the iOS setting, "Settings > Privacy & Security > Microphone". Please visit our iOS app support page for more information on this app.