Set Tone A
Choose its exact frequency, waveform, digital level, and stereo position, or load a useful pair preset.
Two-frequency workspaceLocal audio
Ready — sound is off
Frequency Difference4 Hz
Useful pairs
Browser audio signal toolkit
Dual Tone Generator
Play two controlled browser oscillators together, isolate either source, compare their frequency difference, position them in stereo, or export the combined signal without uploading audio.
What Is a Dual Tone Generator?
A dual tone generator produces two audio waveforms at the same time. Tone A and Tone B have separate frequency, waveform, digital level, stereo pan, and mute settings, while a shared master stage controls the combined output. That arrangement makes a dual tone generator more useful than opening two unrelated players: both sources begin through one deliberate action, their relative settings remain visible, and the mix receives predictable headroom before it reaches the browser output.
The frequency difference readout is the absolute distance between the two requested frequencies. A setting of 440 Hz and 444 Hz therefore shows 4 Hz. Closely spaced tones can create audible level fluctuation called beating under suitable listening conditions, but perception depends on frequency, level, waveform, playback equipment, and the listener. The number is a calculation, not a promise that every pair will produce an obvious beat or that hardware will reproduce both components accurately.
Three simple steps
How to Get Started
Use this dual tone generator deliberately: set the signal, begin quietly, and interpret only what the workflow can actually show.
Set Tone B
Adjust the second source independently and review the calculated frequency difference before playback.
Play and Compare
Start both, preview one tone, mute a source, swap the settings, share the silent configuration, or export a WAV.
Dual Tone vs Single Tone vs Multiple Tone
A single-frequency tool is the clearest choice when one reference tone is enough. This dual tone generator is designed for exactly two components, so the relationship between them remains easy to inspect. A multiple tone generator is better for triads, denser frequency sets, and up to eight independent sources. The focused two-source layout also differs from a sweep, which moves one oscillator through a range instead of holding two frequencies simultaneously.
Understanding Frequency Difference and Audible Beats
When two sine waves are close in frequency and reproduced together, constructive and destructive interference can make the combined level rise and fall near the difference rate. A 440 Hz plus 444 Hz example has a 4 Hz difference. That does not create a separate calibrated 4 Hz output from the speaker, and wider pairs are normally heard as separate pitches or a more complex timbre rather than a slow pulse. Stereo separation can also reduce acoustic interaction compared with sending both sources to both channels.
Common Uses for Two Audio Tones
Students can explore interference, intervals, waveform addition, and stereo placement. Musicians can compare an octave such as 440 and 880 Hz or an approximate 3:2 fifth such as 440 and 660 Hz. Audio users can build a simple repeatable two-component test signal. The 697 and 1209 Hz preset demonstrates the nominal pair for DTMF key 1, while the dedicated DTMF tone generator is the appropriate place for keypad symbols, sequences, and timing controls.
Waveform, Level, and Stereo Controls
Sine waves contain one ideal digital frequency component. Square, triangle, and sawtooth shapes add harmonics, so two identical frequency settings can still sound very different when their waveforms differ. Per-tone level preserves relative balance, pan positions each source between the left and right outputs, and master output changes the managed mix. Percent values are digital gain controls, not decibels sound-pressure level. The combined engine reduces gain according to the active source count to avoid obvious clipping.
Local Sharing and WAV Export
Copy Settings writes a compact query string containing the two frequencies, waveforms, levels, pans, and master setting. Opening that URL restores controls but never starts sound; the canonical page remains the clean route. WAV export creates a five-second stereo PCM file locally, includes short edge fades, applies the same deterministic headroom rule, and preserves relative levels. It does not normalize the result or claim calibrated amplitude, so an exported file remains a practical digital source rather than a laboratory reference.
Browser and Speaker Limitations
The browser schedules mathematically defined oscillators, but the audible result passes through an audio interface, operating-system processing, amplifier, transducer, and room. Sample rate limits the highest representable digital frequency, while real speakers often roll off earlier. Small devices may reproduce neither deep bass nor extreme treble effectively. Distortion can add unintended components, especially with harmonically rich waveforms. Treat observations as properties of the complete playback path rather than proof about the generator alone.
Safe Listening With a Dual Tone Generator
Start with device volume low and use the conservative default digital settings. Two sources can sum, and a tonal signal may feel more intense than ordinary program audio even when a slider value looks modest. Stop immediately at discomfort, avoid prolonged exposure, and do not increase volume simply because an extreme frequency is not audible. This dual tone generator is an audio utility, not a hearing test, medical treatment, or calibrated sound-level instrument.
Clear answers
Frequently Asked Questions
Does the frequency difference equal a third generated tone?
No. The readout is the mathematical difference between Tone A and Tone B. Interference may create audible beating, but the tool does not add a third oscillator at that difference frequency.
Can I play only Tone A or Tone B?
Yes. Use the per-tone Play button for a preview or mute either source while both are running.
Why is the combined signal quieter than expected?
The mixer reserves headroom according to the active tone count so equal-amplitude components are less likely to clip when they add.
Are shared settings URLs indexable frequency pages?
No. Query parameters restore silent tool state, while the canonical URL remains the clean dual-tone route.