Binaural, monaural and isochronic beats
All three put a slow pulse into audio. They differ in where that pulse is created — in your hearing, in the signal itself, or by switching a single tone on and off — and that one difference decides whether headphones are required.
The three names are used almost interchangeably in product copy, which is unhelpful, because they are not variants of the same thing. For the wider context of what this app is, see what Binaural Beats - Brainwaves FM is.
How each one is produced
Binaural beat: made by the listener
Two steady tones a few hertz apart, one sent to each ear and kept separate all the way to the ear. Neither channel contains a pulse: each is a plain, unwavering tone. The pulse is produced when your auditory system compares the signals arriving at the two ears. Because it is never present in the sound itself, a microphone placed between your ears would not record it.
Monaural beat: made in the signal
The same two tones, but combined into one signal before playback. Two tones close in pitch interfere, and the combined waveform rises and falls in loudness at the rate of the difference between them. The pulse is therefore in the audio. Both ears hear it, a microphone records it, and it shows up in any waveform display.
Isochronic tone: made by gating
A single tone switched on and off at a regular rate. There is no second tone and no interference — the pulse is the switching. It is the most obvious of the three to hear, and the easiest to produce.
What that means when you listen
Headphones are required for one of the three. A binaural beat needs the two channels kept apart, which is what stereo headphones do and what speakers, a mono downmix and a single earbud do not. Monaural beats and isochronic tones already carry the pulse in the signal, so they survive speakers, one earbud and anything else that sums the channels. The full account of what preserves and what defeats channel separation is on do you need headphones for binaural beats.
They do not sound alike. A binaural beat is subtle, because it is a comparison your hearing performs rather than a change in the loudness of the track. Monaural beats and isochronic tones modulate loudness directly, so they are plainer to hear and, under quiet music, some listeners find them intrusive. Which of those you want is a preference about the listening experience, and it is a legitimate reason to choose one over another.
Anything that sums to mono changes which one you have. Route a binaural track through a mono path and the effect is gone. Route a monaural or isochronic track through the same path and it arrives intact.
A test that settles which one you have
Play the track through a speaker, or with one earbud in. If a pulse is still audible, the track is monaural or isochronic. If it disappears and the tone becomes flat and steady, it was binaural. This is worth running on anything sold as binaural, because a file that pulses through a laptop speaker is not one.
What the research lets you say about the difference
Less than the comparison articles suggest. Only one study in our source pool compares two of the three directly: Perez, Dumas and Lehmann (2020) measured brain responses to binaural and monaural beats under laboratory control, and found that binaural beats entrained the cortex more weakly than monaural beats, alongside no modulation of mood. Its limitation is its scope: this is laboratory physiology, not an everyday outcome, and it does not establish that monaural beats are the better choice for anything a listener would notice.
Isochronic tones are the least studied of the three. Our source pool contains no trial of them at all. That is not evidence against them — it means there is nothing to summarise, and any page ranking them against the other two is filling that gap with something other than research. Being common in product marketing is not a substitute for having been tested.
The wider picture does not change with the format you pick. Research on binaural beats is mixed, and most studies are small; the reviews, samples and stated limitations are set out on our evidence page, and the short answers are in the FAQ.
Choosing between them
If you do not have headphones, the honest answer is not to look for a more forgiving binaural track. It is that a binaural beat is not what you would be listening to, so choose monaural or isochronic audio — or something else entirely — knowing that no evidence here ranks the three for an outcome.
If you do have headphones, the practical difference is mainly how obvious the pulse is underneath whatever else is playing, and how that sits with you over a long session. Pick the one you can leave running and stop thinking about. Where the numbers attached to these tracks come from, and why frequency lists overstate what is known, is covered on binaural beat frequencies. This is audio, not medical care, and none of the three is a substitute for advice from a clinician.