Real-time spectrum analyzer in the browser
A proper log-frequency spectrum with peak hold, a scrolling spectrogram, an oscilloscope and a vectorscope — free, in the browser, on any audio source.
Who this is for
- Producers checking a mix on a laptop
- Students learning what frequencies look like
- Anyone curious what a song is made of
Log-spaced bands, like your ears
BLOOB computes a 96-band spectrum on octave spacing (30 Hz to 16 kHz) from a 4096-point FFT at 48 kHz, with a music-tuned dynamic range and slow-falling peak caps. Spectrum Bars, Mirror EQ and Radial Spectrum show it three ways, with a frequency scale under the floor.
Spectrogram and scopes
Signal Ridges is a 3D spectrogram scrolling to the horizon. Oscilloscope draws the raw waveform with phosphor persistence; Phase Scope is a vectorscope. Pulse Lanes shows seven instrument lanes over time with kick, snare and hat markers.
Sources
Files, microphone or a browser tab. Use the mic to look at a room, an instrument or a voice.
How to do it
- Open BLOOB and load a file or turn on the microphone
- Choose Spectrum Bars, Mirror EQ or Signal Ridges
- Turn Auto-Director off to freeze the look
- Snapshot saves a double-resolution PNG
Questions people ask about spectrum analyzer online
What is the frequency resolution?
The FFT is 4096 points at 48 kHz (about 11.7 Hz per bin), regrouped into 96 log-spaced bands so the low end is not crushed into a few bars.
Is it calibrated in dB?
The display is music-tuned (roughly -90 to -20 dBFS mapped to the bar height) and not a measurement instrument. It is accurate in shape, not for certification.
Can I see the waveform?
Yes — Oscilloscope shows the time-domain signal, and Waveform Tunnel and Phase Scope build scenes from it.
Does it run on a phone?
Yes, the same analysis runs on iPhone and Android in the browser.
Related: oscilloscope music visualizer · waveform visualizer · free audio visualizer · beat visualizer