About CRUX

What are Binaural Beats?

Binaural beats are an auditory illusion created when two slightly different frequencies are played in each ear. Your brain perceives a third tone — the "beat" — equal to the difference between the two. For example, if 200 Hz is played in the left ear and 210 Hz in the right, your brain perceives a 10 Hz beat. Over time, the brain tends to synchronise its own electrical activity toward that frequency, a process known as brainwave entrainment.

CRUX also includes a set of tracks built on a different principle: alternating left-right audio stimulation. Rather than a frequency difference, these tracks pulse a tone rhythmically between the left and right ears at a steady beat. The result is grounding and physically engaging in a way that complements the binaural sessions — a distinct technique for moments when rhythmic bilateral movement is the goal.

Brain Wave Types

• Delta (0.5–4 Hz): Deep sleep and physical restoration
• Theta (4–8 Hz): Meditation, creativity, and the edge of sleep
• Alpha (8–12 Hz): Calm alertness, relaxed focus, and stress reduction
• Beta (13–30 Hz): Active thinking, concentration, and sustained attention
• Gamma (30–100 Hz): High-level cognition, peak focus, and information processing

What is Noise Therapy?

Noise Therapy uses steady, broadband sound to soften the contrast between quiet and sudden, unpredictable noises — a door slamming, a dog barking — that can jolt the nervous system. By filling the gaps with a constant, predictable backdrop, those startling sounds blend in instead of standing out, giving your brain less to react to. White, pink, brown, and green noise each differ in their balance of high and low frequencies. Green noise sits in the mid-range, centred around 500 Hz — similar in character to a steady waterfall or open nature — and sits naturally between white and pink noise in feel. The Pure Tone option produces a single adjustable pitch you can tune just below your tinnitus to make the ringing less noticeable.

What is Tinnitus?

Tinnitus is the perception of sound — most often a ringing, buzzing, hissing, or humming — with no external source. It originates in the auditory system itself rather than in the surrounding environment, and can range from a barely noticeable background presence to something that regularly interrupts sleep, concentration, or daily life.

For most people it is linked to noise exposure, age-related hearing changes, or periods of heightened stress. While there is no single cure, many find relief through sound: a steady background noise that fills the silence, or a single tone pitched close to the ringing, can reduce how much attention the brain gives to it. CRUX's noise therapy and Pure Tone tool are both designed with that in mind.

What is Box Breathing?

Box breathing is a paced breathing technique — inhale, hold, exhale, hold, each for an equal count — used by everyone from athletes to emergency responders to steady themselves under pressure. The slow, even rhythm and the gentle breath-holds activate the parasympathetic nervous system, the body's "rest and digest" branch, which lowers heart rate and dials down the stress response. With regular practice it becomes a reliable way to return to calm in a couple of minutes.

What is Heart–Brain Coherence?

Heart-brain coherence is a physiological state in which your heart, nervous system, and brain work in sync — reflected in a smooth, ordered heart rate variability (HRV) pattern at around 0.1 Hz, roughly one full breath cycle every ten seconds. In everyday life, our heart rhythm is irregular and reactive; in coherence, it becomes rhythmic and calm, and that ordered signal travels back to the brain via the vagus nerve, promoting emotional stability and a quieter stress response.

The state is reached through two steps working together: slow, paced breathing with a longer out-breath — which directly activates the parasympathetic nervous system — and a genuine feeling of gratitude or appreciation, which amplifies and sustains the coherent rhythm. Research from the HeartMath Institute links regular coherence practice to greater emotional resilience, reduced cortisol, and improved cognitive clarity. CRUX guides you through all three preset breath ratios so you can find the pace that feels most natural.

What is a Body Scan?

A body scan is a guided mindfulness practice in which you move your attention slowly and deliberately through each part of your body — from the crown of your head to the tips of your toes — noticing physical sensations without trying to change them. It is a cornerstone of Mindfulness-Based Stress Reduction (MBSR) and one of the most widely studied mindfulness techniques in clinical research.

Most of us carry tension we are not consciously aware of — a braced jaw, raised shoulders, a breath that never quite fully releases. By resting calm, non-judgmental attention on each area in turn, the body scan gradually signals to the nervous system that it is safe to let go. You are not trying to relax; you are simply noticing — and that noticing is what allows the body to soften on its own. Regular practice reduces stress, improves sleep quality, and builds a more grounded awareness of how emotions show up physically in the body.

Benefits

Delivered across CRUX's tools — binaural beats, noise therapy, box breathing, heart-brain coherence, and body scan.