Sound Power
For everyone who values their hearing
Measure your hearing age and train with sound tuned to your own ears — protect the high-frequency hearing that fades with age.
🔓 What subscription unlocks
- · Full Korean speed-listening course
- · No English, no religion — pure ear training
- · Lossless WAV audio
~$10/mo · free hearing test
▶ Google Play
App Store
Key Features
Hearing Age Test
Find your hearing age from the moment a slowly rising tone becomes clearly audible.
Audible Frequency Test
Record the top frequency you can hear as an objective number — retest a month later and compare the change.
Hearing Rejuvenation Training
High frequencies are the first to fade with age. Speed-listening training helps you keep and sharpen them.
Personal Sound Check
A one-to-two minute check of each ear separately. Bands you hear less well get a gentle boost, and you can A/B the original against your personal sound right after the test.
Sound Sessions
Water sounds with no speech — calm, sleep and focus. Set a length and it stops on its own; it keeps playing with the screen off.
English Listening, Too
Hearing training and English listening in one app — as your ears get younger, English gets easier to catch.
🔊 Ever notice yourself turning the volume up more and more?
With age, the high frequencies fade first. But the ear isn’t just for hearing — it’s the gateway to your brain.
- 20s~17,000 HzWide high-frequency range
- 30s~15,000 HzThe "mosquito tone" threshold
- Early 40s~13,000 HzHigh consonants start to blur
- Late 40s–50s~11,000 HzTV & call volume creeps up
- 60s+~8,000 Hzs, f, th and other highs muddy
Tomatis theory — frequencies above 5kHz are “food for the brain,” feeding focus and alertness.
📺 Why we lose the high notes first (KBS documentary)
🔁 Measure → Train → Retest
A 3-step loop that starts with a number and ends with a number
- 📏
1. Measure (3 free tests)
Test your hearing age, audible frequency, and English listening in minutes to set your own baseline.
- 🎧
2. Train (5–10 min/day)
Listen to Korean audio and repeat it, stepping up from 2× to 5×, while AI scores your pronunciation.
- 📊
3. Retest (see the change)
Measure again after training — compare the old you and the new you, number to number.
🎚️ The training audio is different — WAV original + BrainHZ
We kept the high notes that MP3 throws away
❌ MP3 · Streaming
Compression cuts off frequencies above roughly 16kHz — exactly the high notes that hearing training needs.
✅ WAV original + BrainHZ
Lossless WAV audio plus BrainHZ high frequencies delivers the rarely-stimulated high band clearly.
💬 A user’s experience
A user in their mid-60s first measured a hearing age in the 70s and had to keep the TV nearly maxed out (volume 20). After a month of 30–60 minutes of Korean speed-listening a day, they measured a hearing age in the 20s and turned the TV down to 7.
* Based on subjective, self-measured values; results vary from person to person.
🇺🇸 And a bonus — English-listening ears, too
As you get used to Korean speed-listening, your brain processes faster and your English-listening ears open up too. Hearing training and English listening in one app.
🎧 Measure Your Hearing Age
Earphones on, 3–4 minutes — the same test as the app, right here
Tones of different pitches play several times. Press “👂 Heard” if you hear one, “🚫 Nothing” if you do not. Some trials are silent checks, so concentrate in a quiet place. Takes 3–4 minutes.
A self-check reference only — not a medical diagnosis.
📺 Why do we lose high-frequency hearing first as we age? (KBS)
🔬 Why Hearing Care Matters — the Science
Every claim cites a verifiable primary study.
🧠 Hearing Loss = #1 Modifiable Dementia Risk
The Lancet Commission (2020·2024): ~40% of dementia is preventable, and hearing loss is the single largest modifiable risk factor (7–8%). In the ACHIEVE RCT, hearing intervention cut cognitive decline by 48% in high-risk adults. → This is why hearing care matters.
Source: Lancet 396(2020)·404(2024) · ACHIEVE, Lancet 402(2023) · WHO 2021
👂 Tomatis Method — the Ear Charges the Brain
French ENT Dr. Tomatis: the ear isn't just for hearing — it charges ~30% of the brain's energy, and higher frequencies deliver more of that alertness energy.
Source: Tomatis A., The Conscious Ear (1996)
⚡ 40Hz Gamma Stimulation
MIT Iaccarino (Nature 2016): 40Hz stimulation cleared Alzheimer's proteins (Aβ/Tau) by 37–53% and boosted microglia, neuroplasticity, and neural synchrony. BrainHz applies 40Hz modulation to its audio.
Source: Iaccarino et al., Nature 540:230-235 (2016)
🔁 Senior Neuroplasticity
Merzenich (UCSF): the adult and aging brain can rewire. An aged, dulled auditory cortex can be re-sharpened with repeated auditory training.
Source: Merzenich M., UCSF / Doidge, The Brain That Changes Itself
🦴 Bone Conduction — Bypassing the Eardrum
Delivers sound through bone straight to the cochlea, bypassing the air–eardrum path. Less ear-canal fatigue — good for seniors' long training and bedtime playback.
Source: Stenfelt S. / Shokz (AfterShokz)
🌙 Pink Noise
A 1/f-spectrum natural noise. Northwestern (2017): pink noise during deep sleep enhanced slow-wave sleep and memory consolidation.
Source: Papalambros et al., Front. Hum. Neurosci. (2017)
⏩ Speed Listening — a 'Harder-than-Normal' Signal
2–5x compressed speech gives the auditory cortex a harder-than-normal task, forcing neural reorganization. Start with familiar Korean to raise processing speed.
Source: Speed Listening project / Merzenich (training difficulty)
🎚️ BrainHz Audio Spec
A training-grade sound engine: lossless WAV, restored 16–24kHz highs, and 40Hz modulation combined — keeping the high frequencies MP3 throws away.
Source: BrainHz DSP spec
⚠️ This is educational research citation and does not guarantee prevention or treatment of any disease.
🧠 Why listening alone changes things
The video itself is the training material — try it at 2–4×
Just listening made ears younger
- •2 hearing-rejuvenation videos (senior · junior)
- •The video itself is speed listening (2-4x)
- •Real case: hearing age 70s→20s in a month
25% lower dementia risk — proven
- •US NIH ACTIVE trial (~2,000 people, 20 yrs)
- •Highs (Tomatis) + 40Hz gamma stimulation
- •Fast audio mobilizes the brain's spare capacity
🎬 Sound Power in two minutes
Why this app and what makes it different — in two minutes