See the spectrum of the sound your microphone picks up, as a curve or in 1/3-octave bands, with peak hold. Pair it with pink noise to see how your room or speakers respond.
A free real-time spectrum analyzer (RTA) in your browser. It shows the frequency content of whatever your microphone hears, plus the dominant frequency. Switch between a logarithmic curve and 1/3-octave bands (the 31 standard ISO bands, like a hardware RTA), and turn on peak hold to catch brief peaks and resonances. Pair it with pink noise to see how your room or speakers respond.
How to use it
Enable the microphone, play pink noise through your system and read the response: bumps are room or speaker peaks, dips are cancellations. The 1/3-octave view makes tonal balance easy to read (with pink noise the bars come out roughly flat). It is indicative (the mic is not calibrated), but the trends are real.
Frequently asked questions
What is an RTA / spectrum analyzer?
A real-time analyzer (RTA) splits incoming sound into frequency bands and shows how much energy each one has, right now. It is the classic tool to see the tonal balance of a system or a room.
What can I use it for?
Play pink noise through your speakers and watch the curve to spot room peaks and dips, find resonances or rattles, check whether a subwoofer is too hot, or simply see the spectrum of music or your voice.
What are 1/3-octave bands?
The 1/3-octave view groups the spectrum into the 31 standard ISO bands (20 Hz to 20 kHz), like a hardware RTA. Each bar sums the energy in its band, so with pink noise the bars come out roughly flat — a quick way to read tonal balance and spot room peaks and dips without the noise of a raw FFT curve.
What is peak hold for?
Peak hold keeps the highest level reached in each band (or point of the curve) and lets it fall back slowly. It makes brief peaks and resonances easy to catch — handy when sweeping a tone or feeding pink noise. Use “Reset peak” to clear it and start fresh.