Do solfeggio frequencies require headphones?

No. Unlike binaural beats, solfeggio frequencies work through any speaker: the tone is the same in both ears, so headphones are optional.

What is the difference between the free and Pro version?

The free version gives you all 9 frequencies with pure tones and tuning forks, three 10-minute sessions a day, with ads. The Pro upgrade (€4.89 one-time) removes all ads and the daily limit, extends sessions to 60 minutes, and adds crystal and Tibetan bowl layers and the subliminal message builder.

Which solfeggio frequency is best for sleep?

174 Hz, the lowest and softest tone, is the usual choice for winding down. 396 Hz suits nights when anxiety or a busy mind keeps you awake. Neither has been tested for sleep in a controlled study. Both are available free in the app.

How precise are the frequencies in Solfeggio Sanctuary?

Solfeggio Sanctuary uses Google's Oboe audio library with 32-bit floating-point signal processing. The frequency you set is generated with mathematical precision for the full duration of the session — no drift, no approximation.

Solfeggio Sanctuary: Frequency App for Android, Free + Pro

Start free. Upgrade when you're ready.

The free version gives you all 9 frequencies through pure tones and tuning forks, enough to explore the full solfeggio scale: three 10-minute sessions a day, with ads. Pro removes the ads and the daily limit, extends sessions to 60 minutes, and adds crystal and Tibetan bowls and the subliminal message builder, where you write your own affirmations and layer them beneath the tone.

Free Pro €4.89 once

All 9 solfeggio frequencies ✓ ✓

Pure tones & tuning forks ✓ ✓

Crystal & Tibetan bowls — ✓

Subliminal message builder — ✓

Ads Yes No ads

Sessions 3 a day, 10 min No limit, up to 60 min

No subscription. No recurring charge. Pay once, own it.

Wondering how it compares with free videos? Solfeggio Sanctuary vs YouTube.

Download Free · Upgrade Anytime

Inside the app

Four sounds and a place for your own words

Pick a frequency, a sound and a timer, then press play.

Solfeggio Sanctuary on a phone: the pure tone sound selected at 528 Hz with a 10 minute timer — Pure tones: choose one of the 9 frequencies and a session length. Free.

Solfeggio Sanctuary on a phone: the tuning fork sound selected at 741 Hz with a 20 minute timer — The tuning fork, the other sound in the free version.

Solfeggio Sanctuary on a phone: the crystal bowl sound selected at 396 Hz with a 30 minute timer — Crystal bowl, a Pro sound.

Solfeggio Sanctuary on a phone: the Tibetan singing bowl sound selected at 174 Hz with a 60 minute timer — Tibetan singing bowl, a Pro sound, with sessions up to 60 minutes.

Solfeggio Sanctuary on a phone: the subliminal affirmations window with a preset name, two lines of affirmations, a layer switch and Save and Apply and Load Preset buttons — The subliminal audio builder, a Pro feature: write your own affirmations, save them as a preset and layer them beneath the tone.

What you'll find inside

The 9 Solfeggio Frequencies

Each frequency carries a traditional meaning. Next to it we show what research has actually tested, so you can choose with open eyes.

174 Hz

Foundation

TraditionGrounding, physical ease, pain relief.

ResearchNot tested on its own.

Full reference → 285 Hz

Renewal

TraditionRenewal and "tissue regeneration".

ResearchNo studies; the healing claim is unsupported.

Full reference → 396 Hz

Liberation

TraditionUT: releasing fear and guilt.

ResearchNot tested on its own.

Full reference → 417 Hz

Transmutation

TraditionRE: facilitating change.

ResearchNo peer-reviewed study.

Full reference → 528 Hz

Transformation

TraditionMI: transformation, "DNA repair".

ResearchOne small study (9 people): lower cortisol after 528 Hz music. DNA repair is unsupported.

Full reference → 639 Hz

Connection

TraditionFA: relationships and communication.

ResearchNot tested on its own.

Full reference → 741 Hz

Awakening

TraditionSOL: intuition, expression, "detox".

ResearchNot tested; the detox claim is unsupported.

Full reference → 852 Hz

Intuition

TraditionLA: inner clarity, spiritual order.

ResearchNot tested on its own.

Full reference → 963 Hz

Divine Connection

Tradition"Divine connection", the pineal gland.

ResearchNot tested; the pineal claim is unsupported. Bright and activating: keep sessions short.

Full reference →

Want to compare them side by side? See the full solfeggio frequencies chart, with the nearest musical note, traditional use and what the evidence says for each one.

Why audio quality matters

Built on professional audio infrastructure

Solfeggio Sanctuary runs on Google's Oboe audio library, the same low-latency C++ engine used in professional Android audio applications. This means the frequencies you hear are mathematically precise. No compression artifacts. No drift. The 528 Hz you're listening to is actually 528 Hz.

Audio Engine Oboe / C++

Signal Processing 32-Bit Float

Frequency accuracy Mathematically exact

★★★★★

"Exactly what I was looking for. No unnecessary frills, all frequencies are available for free."

Google Play Store review

Common questions

Do I need headphones?

No. Unlike binaural beats, solfeggio frequencies work through any speaker: phone, Bluetooth, or room speaker. Headphones improve focus but are not required for the mechanism to work.

What's the difference between Free and Pro?

Free gives you all 9 frequencies with pure tones and tuning forks, three 10-minute sessions a day, with ads. Pro (€4.89 one-time) removes all ads and the daily limit, extends sessions to 60 minutes, and adds crystal and Tibetan bowl layers and the subliminal message builder. No subscription in either version.

What is the subliminal message builder?

A Pro feature: you write your own affirmations and the app layers them beneath the frequency during the session. Your text stays on your device. Hidden messages on their own have shown no effect in research on subliminal self-help audio (Greenwald et al., 1991), so use the builder to bring your own intentions into the session, and read or say the words yourself as well. More on how beliefs change, and what affirmations can and cannot do.

Which frequency should I start with?

396 Hz for anxiety or stress. 417 Hz for a morning reset. 528 Hz for focus and clarity. 174 Hz for physical tension or sleep. All are in the free version. Try them and see what works for you.

How precise are the frequencies?

Mathematically exact. The app uses Google's Oboe audio library with 32-bit floating-point signal processing. The frequency you set is the frequency delivered. No drift, no approximation.

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How does it compare?

Solfeggio Sanctuary vs YouTube Tones generated live, offline and with the screen off. Ad-free for €4.89 once vs a monthly subscription. Read comparison →