Everything you need to know about Web Audio FFT analysis, pitch detection, phase scope, and spectrograms.
1. Are my audio files or microphone streams uploaded to any cloud servers?
No. ShiftTools Audio Analyzer runs 100% client-side inside your web browser's local memory using the Web Audio API. Zero audio bytes or microphone recordings leave your device.
2. What is the difference between Logarithmic and Linear frequency scales?
Logarithmic scale mirrors human auditory pitch perception (giving equal visual width to low sub-bass 20-200Hz and upper trebles). Linear scale spaces all Hz bins evenly across the canvas width.
3. How does the Stereo Phase Scope detect mono compatibility issues?
The Lissajous phase scope plots Left channel amplitude against Right channel. A vertical line indicates mono audio, a circular/elliptical cloud indicates wide stereo width, and horizontal dispersion warns of out-of-phase audio that will cancel out when played on mono speakers.
4. What FFT size should I select for analyzing audio?
Use 1024 / 2048 for fast transient drum analysis, 4096 for balanced music production, and 8192 / 16384 for high-resolution sub-bass & vocal pitch inspection.
5. How does the fundamental pitch (f₀) detector work?
The pitch detector runs a YIN auto-correlation algorithm on the time-domain waveform buffer to find the repeating period of the sound, converting it directly into exact Hz and musical note pitches (e.g. 440.0 Hz = A4).
6. What audio file formats are supported for local analysis?
The tool supports all browser-native audio formats including MP3, WAV, FLAC, M4A, AAC, OGG, WebM, and AIFF.
7. Can I analyze microphone input in real-time?
Yes. Click the Live Microphone tab and grant permission. The Web Audio API will route your mic input directly to the FFT, Spectrogram, Oscilloscope, and Pitch detector in real-time.
8. What do the 4 Spectrogram color palettes represent?
Cyberpunk Neon emphasizes high frequency transients, Inferno uses hot thermal colors for dB intensity, Viridis is perceptually uniform for scientific acoustic auditing, and Matrix offers high contrast monochrome inspection.
9. How do I export a high-resolution PNG analysis report?
Click the "Export High-Res PNG Report" button in the right sidebar. The tool will snapshot all 4 visualizer canvases and composite them with embedded acoustic metrics (peak dBFS, pitch, RMS, LUFS) into a single PNG file.
10. Does this tool work offline or in air-gapped corporate environments?
Yes. Once the web page is loaded, the entire Web Audio processing pipeline operates 100% offline without requiring internet connectivity.
11. What is Peak dBFS and how do I detect clipping?
dBFS stands for Decibels Relative to Full Scale. If your audio signal exceeds 0.0 dBFS, digital clipping occurs, triggering the red clipping indicator on the channel meters.
12. Can I use the synthetic generators to test my speakers or room acoustics?
Yes. Use the 20Hz-20kHz Log Sweep to test speaker frequency response or Pink Noise to measure room standing waves and acoustic resonance.
13. Why is zero-crossing synchronization used in the Oscilloscope?
Zero-crossing synchronization aligns the start of each drawn waveform frame to when the signal crosses 0 amplitude upwards, producing a rock-steady, non-flickering waveform display.
14. What is the difference between Peak dBFS and RMS Loudness?
Peak dBFS measures the maximum momentary spike in signal voltage, whereas RMS (Root Mean Square) measures average continuous audio power, matching human perceived loudness.
15. Is there a file size limit for loading local audio tracks?
There is no hard file size limit. Audio files up to 500MB+ stream smoothly into Web Audio buffer sources without crashing browser memory.