# MentalWave

> MentalWave is an iPhone app of binaural beats, Solfeggio frequencies and soft melodic mixes for sleep, relaxation and focus. Tune your own frequency on the Pad, layer rain, waves or a singing bowl, and set a gentle sleep timer. Made by Yellow Cat Labs. MentalWave is a wellness app for relaxation, sleep and focus, not a medical device.

Key facts:
- Platform: iPhone, iOS 26.2 or later. App language: English.
- Goals offered at setup: sleep, stress, focus, migraine-prone days, tinnitus.
- Library: 49 sounds in six sections (Fall asleep tonight, Stop overthinking, Focus, Healing frequencies, Pure noise, Pure tones). Most are melodic mixes: a binaural beat under a soft melody and a nature bed.
- Sound types: binaural beats (headphones), isochronic tones (work through speakers), pure tones, brown, pink and white noise, nature layers (rain, sea, fire, storm) and melody layers (garden, halo, flow, singing bowl, dream, om).
- The Pad: drag to set a carrier tone (80 to 1000 Hz) and a beat (0.5 to 40 Hz); the app names the band.
- Other features: sleep timer with fade-out, lock screen and AirPlay controls, Backdrop mode (plays over other audio), favourites, saved mixes, search by name or frequency.
- Price: free download (a free sound in every section, the three noises, three pure tones, nature layers, listening and timers up to 30 minutes). MentalWave Premium: €49.99 per year, with a 7-day free trial, or €9.99 per month.
- Privacy: no account; sounds are generated on the iPhone and play offline.
- Brainwave bands as used in the app: Delta 0.5–4 Hz (Deep, slow-wave sleep. Used in the sleep mixes); Theta 4–8 Hz (Drowsiness, daydreaming and meditation); Alpha 8–12 Hz (Relaxed wakefulness: calm, but awake); Beta 12–30 Hz (Active thinking and focus); Gamma 30–40 Hz (Alert attention. 40 Hz is the most studied).
- Contact: contact@yellowcatlabs.com. Privacy policy: https://yellowcatlabs.com/privacy-policy

## Pages

- [Home](https://mentalwave.app/): what MentalWave is, features, pricing and FAQ
- [Sound library](https://mentalwave.app/sounds/): all 49 sounds with their carrier and beat frequencies
- [Research](https://mentalwave.app/science/): the published studies the app cites, with links
- [Support](https://mentalwave.app/support/): headphones, free limits, subscriptions, contact
- [Guides](https://mentalwave.app/guides/): articles on binaural beats, sleep, focus and tinnitus

## Guides

- [Binaural beats for sleep: which frequency to use, and what studies show](https://mentalwave.app/guides/binaural-beats-for-sleep/): For sleep, most people use delta binaural beats between 0.5 and 4 Hz, often after a few minutes of theta (4 to 8 Hz) to wind down. In a small lab study, a 3 Hz beat lengthened deep sleep, and steady broadband sound helped people fall asleep faster. Evidence is promising but limited, so treat beats as part of a calm bedtime routine, at low volume, with a timer. (Markdown: https://mentalwave.app/guides/binaural-beats-for-sleep.md)
- [Solfeggio frequencies explained: 396, 528, 852 Hz and 432 Hz, honestly](https://mentalwave.app/guides/solfeggio-frequencies-explained/): Solfeggio frequencies are a set of tones (174, 285, 396, 417, 528, 639, 741, 852 and 963 Hz) popularised in the 1990s and linked by their promoters to healing and spiritual meanings. There is no good evidence that a specific frequency heals the body; the few small studies on 528 Hz and 432 Hz music found modest relaxation effects at best. They can still be pleasant, calming tones to listen to. (Markdown: https://mentalwave.app/guides/solfeggio-frequencies-explained.md)
- [Sounds for tinnitus: how sound enrichment helps, and which noise to try](https://mentalwave.app/guides/sound-therapy-for-tinnitus/): Sound therapy uses gentle background sound, such as pink or brown noise, rain or soft music, so that tinnitus stands out less against silence. Hearing organisations recommend it as part of tinnitus care, especially at night. The evidence that sound alone reduces tinnitus is limited, so the aim is relief and better sleep, not a cure. Keep the sound just below the level of your tinnitus. (Markdown: https://mentalwave.app/guides/sound-therapy-for-tinnitus.md)
- [What are binaural beats? How they work and what the research says](https://mentalwave.app/guides/what-are-binaural-beats/): A binaural beat is a slow pulse you perceive when each ear hears a pure tone at a slightly different pitch, for example 200 Hz in the left ear and 210 Hz in the right, which you hear as a 10 Hz beat. It needs headphones. Studies link binaural beats to lower anxiety and small effects on attention and sleep, but many studies are small and results vary from person to person. (Markdown: https://mentalwave.app/guides/what-are-binaural-beats.md)
- [40 Hz binaural beats for focus: what the research says](https://mentalwave.app/guides/40-hz-binaural-beats/): 40 Hz binaural beats sit in the gamma band, which is linked to alert attention. In small lab studies, listening to 40 Hz beats was linked to a narrower focus of attention and, for some people, fewer missed targets in fast attention tasks. The effects are modest, vary between people, and reviews find that beats do not reliably change brainwaves, so treat 40 Hz as one option for focus, not a guaranteed boost. (Markdown: https://mentalwave.app/guides/40-hz-binaural-beats.md)