Sounds and frequencies are two different things

This is the single most important thing to understand, and everything else in the app makes sense once you have it.

A sound is an audio file. Rain, a fireplace, a sound bath, a piece of ambient music. It streams from our servers, or plays from your device if you downloaded it. It needs a connection unless you have saved it offline. Sounds live under Discover Sounds, Sound Healers, and the daily recommendation on your home screen.

A frequency is a generated tone measured in hertz. Your phone creates it in real time. No streaming, no Wi-Fi, no cellular. This is what makes the headphones vibrate. Frequencies live in the Generator, in the Frequency Library, and inside the combined presets on the home screen.

Some parts of the app play both at once. The preset combinations on the home screen, for example, layer a calm sound over two generated tones. Quantum Calm plays its sound while generating 110 Hz in your left ear and 103 Hz in your right.

Quick test: if you put the headphones on and feel nothing, you are almost certainly playing a sound with no frequency behind it. Open the Generator and start a frequency, then overlay the sound on top.