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639 Player Plus

639 Hz · Patent-Protected · US 11,836,330

Retune Your Music To 639 Hz

The frequency of connection, repair, and shared rooms.

Get 639 Player Plus How it works
● Free 20-song trial ● $19.99 unlocks 639 Hz ● $99.99 unlocks all 10 ● No ads, no tracking ● 14-day refund

See it work

See 639 Player Plus retune music in real time

Sixty seconds. Real-time 639 Hz retune of a song you'll recognise.

Trouble loading? Watch on YouTube

Why 639 Player Plus

Built for people who own their music — and want to hear it differently.

  • Heart-Chakra Tone

    The fourth solfeggio frequency — traditionally associated with the heart, with relationships, and with communication.

  • Shared Spaces

    A common pick for music played in shared rooms — kitchens, dinners, workplaces with people in them.

  • Patent-Protected Retune

    Real-time conversion of your existing library, US Patent 11,836,330.

  • No Tracking, No Ads

    One-time $19.99 per platform. No subscriptions, no listening telemetry, no upsells.

How it works

Real-time retuning. No re-encoding. No quality loss.

We don't make copies of your songs. We don't apply equalization or compression. We shift the pitch of the audio stream as it plays — and that's the entire trick.

  1. 01

    Add your music

    Point 639 Player Plus at a folder on your device — MP3, FLAC, WAV and most other common formats are supported. Your files stay where they are; nothing is uploaded.

  2. 02

    Tap to retune

    One tap and the entire library plays at 639 Hz. The original files aren't touched — the retune happens in real time on the way to your headphones.

  3. 03

    A/B as you go

    Switch back to 440 Hz any time. Compare the same song side-by-side and decide for yourself. Set a sleep timer, build playlists, listen offline.

Patent-protected. The real-time frequency-changing engine in 639 Player Plus is covered by US Patent 11,836,330 — so the option to retune your own music can't be quietly taken away from you.

Why we built 639 Player Plus

TODO_UNIQUE_COPY — 300+ words. Angle: 639 Hz as the music for shared spaces. Distinct from 528 (interior). Voice: SYQEL indie.

From the audience

Loved by listeners who own their music.

  • "TODO_UNIQUE_COPY"
    TODO
    iOS user
  • "TODO_UNIQUE_COPY"
    TODO
    Android user
  • "TODO_UNIQUE_COPY"
    TODO
    macOS user

Get the app

Try free. Upgrade once.

No ads. No tracking. No subscriptions. 14-day money-back guarantee on every paid tier.

  • Free trial

    $0

    20 retunes. No card. Just open the app and try it.

  • Unlock 639 Hz

    $19.99

    One-time. 639 Hz unlocked forever on this platform. Add other frequencies later for $19.99 each.

  • Unlock all 10

    $99.99

    One-time. 639 Hz plus all 9 solfeggio tunings (174, 285, 396, 417, 528, 639, 741, 852, 963).

Download for App Store iPhone & iPad Download for Google Play Android Download for macOS Apple Silicon & Intel Download for Windows Windows 10 / 11

Prefer a direct installer? Windows .exe · Mac .dmg

Patent-protected by US Patent 11,836,330 · Built and self-funded by SYQEL INC

FAQ

Quick questions

What is 639 Hz used for?

TODO_UNIQUE_COPY

How is 639 Hz different from 528 Hz?

TODO_UNIQUE_COPY

Can I play 639 Hz music in a shared space?

TODO_UNIQUE_COPY

What formats does the app support?

MP3, FLAC, WAV, and most other common audio formats.

Is it a one-time purchase?

Try it free for 20 retunes, then $19.99 unlocks this frequency permanently. Want all 10? $99.99 one-time. No subscriptions, ads, or tracking.

The other tunings

Looking for a different frequency?

We make a player for each tuning so you can pick the one that fits what you're after. Every app uses the same patent-protected real-time engine.