Audio Spectrum Analyzer — Open Source Media Player App

Audio Spectrum Analyzer was designed with accuracy and ease of use in mind. It can be used for monitoring or measuring environmental sound or noise; help tuning instruments; timing short sound events; and educational purpose.
Features: * No Ads. * With log or linear frequency axis. * Can label frequency axis using music pitch note. * Support all possible sampling rates and almost all recorder sources of your device. * Graph with nice grid lines and labels, easy to operate. * FFT sample size range from 64 to 32768. Using half-overlapped (adjustable) time window to increase time resolution. * Various window functions provided, for different frequency resolution and dynamical range. * Peak frequency detection (in unit of Hz and note+cent), with a moderate accuracy (FFT + interpolation). * With dB or A-weighting dB (dBA). * Can record the audio in wav (PCM) format. * Pinch to zoom, drag or swipe to move, long-press to place cursor, double touch to reset zoom. Notes: May need some knowledge of discrete Fourier transform and spectrum analysis to use it well. The actual accuracy mainly depends on your device. No calibration interface provided.