What are isochronic tones?
How is it made?
A carrier tone (e.g. 220 Hz) is switched on and off at a constant rate (e.g. 10 Hz) with a soft-edged envelope. Hard edges would cause clicks; Frekans Studio shapes the pulses smoothly and tests that no clicks occur.
Unlike a monaural beat, the fluctuation comes not from two interfering tones but from a single tone being switched on and off. The result is a sharper, rhythmic pulse.
What does research say?
A measurable EEG response appears at the pulse rate. However, few studies directly test outcomes such as relaxation or focus; in a surgical trial in Türkiye, isochronic tones did not reduce anxiety compared with a group that heard no sound.
What does the evidence say?
Evidence for effects on relaxation or focus is insufficient; we offer it as a listening experience.
■ D · Insufficient evidence- What do we know?
- Monaural beats produce a measurable EEG response at the beat rate; in a 16-person study it was stronger than for binaural beats, while mood did not change. The linked sources have no EEG data for isochronic tones. In people prone to mind wandering, monaural theta beats reduced mind wandering compared with a sine tone; a reduction compared with silence appeared only in a subgroup.
- What don't we know?
- Very few controlled studies test effects on relaxation or focus directly. In a surgical trial with 90 patients in Türkiye, isochronic tones did not reduce anxiety compared with no sound.
No method has been shown to be superior.
■ D · Insufficient evidence- What do we know?
- In a 16-person EEG study, monaural beats produced a stronger cortical response than binaural beats, but mood did not change with either. In a surgical trial with 90 patients, there was no anxiety difference between binaural and isochronic groups. In a 221-person home study, monaural and binaural beats did not differ from each other or from a beat-free sound in sleep latency.
- What don't we know?
- There are not enough studies directly comparing the methods on meaningful outcomes, and a stronger EEG response has not been shown to mean a better outcome.
Evidence levels and sources come from the database; the article adds no new claims. Evidence methodology
Frequently asked questions
- Which method for 40 Hz?
- Binaural perception weakens above 30 Hz, so isochronic or monaural methods are used for high pulse rates. See the 40 Hz page for the evidence level of related claims.
- Does the screen flash too?
- No. Frekans Studio never flashes any visual at the pulse or beat rate; nothing flashes more than 3 times per second (WCAG 2.3.1).
Listen and try
Last updated: 1 October 2026 · This article is for information only; it is not medical advice.