Multi Tone Generator

Stack several tones into a chord or custom spectrum.

Everything runs in your browser. No audio is ever uploaded.

Chord presets

FrequencyHz

Note nameType a note such as A4, C#3 or Bb2 to set this voice.

Waveform

Level0 dB

Balance0

Settings

Volume-12 dB

Audio starts on your first tap on Play, as required by your browser. Press Space to start or stop.

A multi tone generator plays several pure tones together instead of one. Use this chord generator, or additive tone generator, to stack up to eight voices, give each one its own frequency, waveform, level and stereo position, and hear an interval, a chord or a harmonic series as bare sine waves.

How to use it

Start from a preset if you want a known shape. Major triad, minor triad, perfect fifth and octave all build on middle C at 261.63 Hz and replace whatever is loaded.
Set each voice. Every voice has a frequency slider, a number field in hertz and a note name field, so you can type A4, C#3 or Bb2 instead of doing the arithmetic. The nearest note name is shown next to the field as you move.
Add or remove voices. Add voice goes up to eight; Remove takes one away as long as more than one is left.
Mix them. Each voice has its own level from -30 dB to 0 dB, its own balance between left and right, and Mute and Solo buttons for pulling one line out of the stack.
Pick a waveform per voice, set the master volume, then press Play or hit the space bar. Your voices are kept in this browser, so the stack is still there next time.

What you can use it for

Hearing what an interval really is. Without the timbre of an instrument in the way, a fifth, a third and an octave are much easier to tell apart, and the difference between a major and a minor triad becomes obvious.

Building a tone from its harmonics. Set voices to 200, 400, 600 and 800 Hz, then bring them in one at a time with the level sliders. That is additive synthesis, and it explains why a square wave sounds hollow and a sawtooth sounds bright.

Ear training. Solo and mute let you hear one voice on its own and then back in context, which is the fastest way to learn to pick a single note out of a chord.

Loading a speaker properly. Several tones at once demand far more from an amplifier and a driver than a single sine does, so a stack of voices exposes strain that one tone hides.

Placing sound in the stereo field. Give each voice its own balance setting and you can check that a mixer, a headset or a surround setup puts each element where it should be.

Intervals and their frequency ratios

Interval	Pure ratio	Second voice above 220 Hz
Octave	2:1	440 Hz
Perfect fifth	3:2	330 Hz
Perfect fourth	4:3	293.3 Hz
Major third	5:4	275 Hz
Minor third	6:5	264 Hz
Whole tone	9:8	247.5 Hz

Accuracy and limits

The ratios above are the pure ones. Note names and the chord presets use equal temperament with A4 at 440 Hz, which spreads a small error across every interval so that all keys work. A major third built that way is about 14 cents wide of 5:4, and with plain sine waves you can hear it beating. That is the tuning system, not a fault in the tool.

Voices add up. Eight tones at 0 dB carry far more energy than one, so the master volume needs to come down as you add them, and a small speaker asked to play a loud stack will distort before it gets loud. Set the level low, then raise it.

Output is not calibrated and the browser is not a synthesizer. There is no envelope, no detune and no export here: the mix plays live, the frequency field rounds to whole hertz, and everything above 20 kHz or below 20 Hz is out of range on purpose.

Frequently asked questions

What is a multi tone generator used for?

Anything that needs more than one frequency at the same time: hearing an interval or a chord as pure tones, building a harmonic series by hand, loading a speaker with a demanding signal, or checking stereo placement voice by voice.

How many tones can I play at once?

Eight. Each one has its own frequency, waveform, level and balance, and you can mute or solo any of them while the rest keep playing.

Why does the major triad sound slightly rough?

Because it is in equal temperament, like a piano. The third is a little wider than the pure 5:4 ratio, which produces a slow beating that instruments normally hide behind their own timbre. Type the pure frequencies by hand and the roughness disappears.

Can I enter notes instead of frequencies?

Yes. Type a note name such as A4, C#3 or Bb2 in the note field of any voice and it is converted to hertz at A4 equals 440 Hz. The nearest note name is also displayed next to the frequency as you drag.

Does it remember my setup?

Yes. The voices you build are saved in this browser only, so the stack comes back on your next visit and nothing about it is sent anywhere.

Can I download the chord as a file?

Not from this page. The multi tone generator plays live only. If you need a file, the tone generator and the sweep generator both render a WAV in the browser.