A lightweight Windows tone generator that produces pure sine tones from first principles. No samples, no synth libraries -- every sound you hear is computed mathematically in real time. Built in C with the classic Win32 look.
New in 1.1: audio now plays out over WASAPI (shared mode) in 32-bit float — the native format of the modern Windows mixer — instead of the legacy 16-bit
waveOutpath. The synthesis engine is unchanged; the signal just no longer round-trips through a 16-bit conversion, and the event-driven path tightens how quickly parameter changes become audible.waveOutremains as an automatic fallback. See Audio Output below.
- Run ToneGen.exe (no installation required).
- Pick a preset from the dropdown, or type a frequency into the Custom field and click outside it to confirm.
- Click Play. You will hear a pure sine tone.
- Drag the Volume slider to adjust loudness.
- Click Stop to fade out cleanly.
Note: After typing a custom frequency, press Enter or click outside the edit field to confirm the value.
Both ears receive the same frequency. Good for meditation drones, tuning instruments, or testing speakers.
Each ear receives a slightly different frequency. Your brain perceives a rhythmic "wobble" at the difference between the two. This perceived wobble is the binaural beat.
Two dropdowns let you compose a session independently. The Carrier dropdown sets the pitch you consciously hear -- a neutral 200 Hz, the Solfeggio frequencies, or concert tunings (Middle C, A432, A440). The Beat dropdown sets the brainwave target your mind entrains to: Delta 2 Hz, Theta 6 Hz, Schumann 7.83 Hz, Alpha 10 Hz, SMR 14 Hz, Beta 20 Hz, Gamma 40 Hz. Each picks into the Base and Beat fields, which you can still edit by hand; a field that matches no preset shows -- Custom --.
Headphones are required for binaural beats to work -- speakers mix the channels and cancel the effect.
Generates continuous noise for focus, sleep, or masking. Three types:
| Type | Spectrum | Sound |
|---|---|---|
| White | Flat (equal energy at all frequencies) | Classic static |
| Pink | 1/f (equal energy per octave) | Balanced, natural. Good for focus and sleep |
| Brown | 1/f² (deeper rolloff) | Rumbling waterfall / distant thunder. Deep relaxation, tinnitus relief |
All three produce true stereo noise (independent L/R channels for a spacious, natural sound).
A binaural beat is not a real sound in the air. It is created by your brain when it receives two close but different frequencies, one in each ear. The brain perceives a pulsing tone at the difference frequency.
Example: Left ear = 200 Hz, right ear = 207.83 Hz. Your brain hears a steady tone around 200 Hz with a 7.83 Hz wobble layered on top. That wobble is the binaural beat. You cannot hear 7.83 Hz directly (it is far below the ~20 Hz threshold of human hearing), but through the binaural effect your brain entrains to it.
The formula:
binaural beat frequency = |right ear - left ear|
So to target a specific binaural beat:
right ear = left ear + desired beat
The "left ear" frequency (the carrier or base) can be anything comfortable to listen to. Most people use 100--400 Hz as a carrier. The carrier is what you consciously hear; the beat is what your brain entrains to.
- Switch to Binaural mode.
- Type your carrier into the Base field (e.g.
200). - Type your desired binaural beat into the Beat field (e.g.
7.83). - The program automatically calculates:
- Left = Base = 200.000 Hz
- Right = Base + Beat = 207.830 Hz
- Put on headphones and click Play.
| Goal | Base | Beat | Left | Right |
|---|---|---|---|---|
| Schumann 7.83 Hz | 200 | 7.83 | 200 Hz | 207.83 Hz |
| Alpha 10 Hz | 150 | 10 | 150 Hz | 160 Hz |
| Gamma 40 Hz | 300 | 40 | 300 Hz | 340 Hz |
- Switch to Binaural mode.
- Tick "Advanced (set L/R directly)".
- Type the exact frequency for each ear.
This gives you full control. The binaural beat is always |R - L|.
| Goal | L | R | Resulting Beat |
|---|---|---|---|
| Schumann 7.83 Hz | 200 | 207.83 | 7.83 Hz |
| Theta 6 Hz | 250 | 256 | 6 Hz |
| Pure unison (no beat) | 432 | 432 | 0 Hz |
Tip: For effective brainwave entrainment, keep the beat frequency below ~40 Hz and keep L and R within about 30 Hz of each other. Wider gaps produce an audible pitch difference rather than a perceived wobble.
Human hearing ranges from roughly 20 Hz to 20,000 Hz. Many of the frequencies in the reference table below are far below 20 Hz. You cannot hear them as a direct tone through speakers.
Use them as binaural beats instead: set the frequency as the Beat value, pick a comfortable Base, and wear headphones. The status bar will warn you if you try to play a sub-audible frequency in Single mode.
Requirements: MinGW-w64 (gcc) and GNU make.
make # Build ToneGen.exe
make test # Run the unit tests (15 tests)
make clean # Remove built files
Frequencies commonly discussed in healing, meditation, brainwave entrainment, and new age contexts. Ranked roughly from most widely cited to least.
Frequencies marked with * are below 20 Hz and should be used as binaural beats, not direct tones.
| # | Hz | Name | Association |
|---|---|---|---|
| 1 | 432 | Verdi tuning / "Natural" A | Claimed to resonate with nature and water; popular alternative to standard 440 Hz |
| 2 | 528 | Solfeggio MI | "Love frequency" / "DNA repair" -- the most cited solfeggio; also called the "miracle tone" |
| 4 | 396 | Solfeggio UT | Liberating guilt and fear |
| 5 | 417 | Solfeggio RE | Facilitating change, undoing situations |
| 6 | 639 | Solfeggio FA | Connecting and relationships |
| 7 | 741 | Solfeggio SOL | Awakening intuition, expression |
| 8 | 852 | Solfeggio LA | Returning to spiritual order |
| 9 | 963 | Solfeggio | Pure miracle tone / pineal gland activation / "frequency of God" |
| 10 | 174 | Solfeggio (extended) | Natural anaesthetic, foundation, pain reduction |
| 11 | 285 | Solfeggio (extended) | Healing tissue, cellular repair |
| 13 | 440 | Standard concert pitch A4 | Universal tuning reference |
| 14 | 256 | Scientific C / Verdi C | C4 in scientific tuning (A=432); sometimes called the "healing C" |
| # | Hz | Wave | Association |
|---|---|---|---|
| 3 | 7.83* | Schumann resonance | Fundamental electromagnetic resonance of the Earth's cavity; grounding, calm, connection to nature |
| 12 | 40* | Gamma | Insight, peak focus, higher cognitive function; research links 40 Hz to clearing amyloid plaques (Alzheimer's research) |
| 15 | 10* | Alpha | Relaxation, calm alertness, light meditation; the classic "alpha state" |
| 16 | 4* | Theta | Deep meditation, dreaming, intuition, subconscious access |
| 17 | 1.5* | Delta | Deep dreamless sleep, healing, regeneration |
| 18 | 14* | SMR | Sensorimotor rhythm -- relaxed focus, calm body with alert mind; used in neurofeedback |
| 19 | 20 | Low beta | Edge of audibility -- mental alertness, active thinking |
| 29 | 3.5* | Deep theta | Schumann 2nd harmonic region -- profound meditation, trance states |
| 31 | 0.5* | Epsilon | Extremely deep states, suspended animation, extraordinary meditation |
| 37 | 7* | Theta-alpha border | Creativity, visualization, "the twilight zone" between waking and sleep |
| 41 | 2.5* | Deep delta | Cellular regeneration, growth hormone release, immune system support |
| 42 | 12* | Alpha-beta border | Centered awareness, cognitive bridge; used in learning and focus protocols |
| 43 | 15* | Beta | Active concentration, analytical thinking, problem-solving focus |
| 44 | 6.3* | Theta (mid-range) | Creative visualization, emotional processing, self-healing |
| 51 | 0.1* | Hyper-delta / lambda | Sometimes cited as a carrier for "whole-brain synchronisation" |
| # | Hz | Body | Association |
|---|---|---|---|
| 21 | 136.1 | Earth year (OM) | Cosmic Octave of the Earth's year; used in Indian classical music as the reference SA |
| 22 | 126.22 | Sun | Earth's orbital period around the Sun, octaved up |
| 23 | 194.18 | Earth day | One Earth rotation (24 hrs) octaved into audible range |
| 24 | 210.42 | Moon | Synodic month octaved up; associated with the sacral chakra |
| 25 | 221.23 | Venus | Venus orbital period octaved into audible range |
| 26 | 144.72 | Mars | Strength, energy, willpower |
| 27 | 172.06 | Platonic year | Precession of the equinoxes (~25,772 yrs) octaved up; higher spiritual connection |
| 45 | 187.61 | Mercury | Mental clarity, communication |
| 46 | 295.7 | Saturn | Discipline, structure, boundaries |
| 47 | 207.36 | Uranus | Spontaneity, revolution, awakening |
| 48 | 211.44 | Neptune | Intuition, dreams, the unconscious |
| 49 | 140.25 | Pluto | Transformation, regeneration, hidden depths |
| # | Hz | Name | Association |
|---|---|---|---|
| 20 | 111 | "Holy frequency" | Measured resonance in ancient temples (Hypogeum of Malta); said to stimulate the prefrontal cortex |
| 28 | 473 | Solfeggio (extended) | Bridging frequency between heart and throat |
| 30 | 33* | Christ consciousness | Cited in some traditions as a resonance of spiritual awakening |
| 32 | 288 | Double 144 | Numerological frequency; associated with abundance and light body activation |
| 34 | 360 | "Balance" | 360 degrees of the circle; associated with wholeness and joy |
| 35 | 480 | "Liberation" | Third harmonic of 160; sometimes cited as a liberation frequency |
| 36 | 720 | Higher-octave healing | Sometimes cited as a higher-octave healing frequency |
| 38 | 108 | Sacred number | 108 is sacred in Hinduism, Buddhism, and Jainism; used in sound healing |
| 39 | 128 | Bone conduction C | Two octaves below 512 Hz (medical tuning fork C); bone conduction healing |
| 40 | 512 | Medical tuning fork C | Used in clinical diagnostics and sound therapy |
| 50 | 27.5 | Sub-bass A0 | Lowest A on a standard piano; at the edge of hearing, felt more than heard |
| 52 | 50 | Gamma (low) | Also mains hum in Europe; some cite 50 Hz as a vitality frequency |
| 53 | 384 | "Truth" | Two octaves of 96; called the "truth frequency" in certain healing lineages |
| 54 | 586 | Higher Solfeggio RE | Sometimes cited as a higher expression of 417 Hz |
| 55 | 888 | "Angel number" | Popular in numerology-based sound healing; associated with abundance |
The 40Hz Brain Cleaner is a dedicated mode at the bottom of the app that replicates the auditory stimulation protocol from MIT's GENUS research (Gamma ENtrainment Using Sensory stimuli). Click Start (60 min) and it takes over -- all other controls are disabled, and the program plays precisely timed 1 ms tone pips at 10 kHz, repeating at exactly 40 Hz, matching the protocol described in the peer-reviewed literature below. The session runs for exactly 60 minutes (the clinical protocol dosage) with a countdown timer, then stops automatically.
Warning: High volume levels may damage hearing. Start at a low volume and increase gradually. Use at your own risk.
Gamma oscillations (~40 Hz) are natural brain rhythms tied to attention, perception, and memory. In Alzheimer's disease, these oscillations are disrupted. The 40 Hz auditory stimulus drives an Auditory Steady-State Response (ASSR) -- the brain's auditory cortex locks onto the 40 Hz repetition rate, producing strong gamma-frequency neural activity. This entrained gamma activity has been shown in research to:
- Activate microglia (the brain's immune cells) to clear amyloid-beta plaques and tau tangles
- Improve cerebral blood flow and vascular function
- Reduce neuroinflammation
- Strengthen synaptic connections
- Improve memory consolidation
The work comes from Li-Huei Tsai's lab at MIT's Picower Institute for Learning and Memory. It is among the most promising non-pharmaceutical approaches to Alzheimer's disease currently under investigation.
| Year | Paper | Key Finding |
|---|---|---|
| 2016 | Iaccarino et al., Nature 540(7632), 230-235. doi:10.1038/nature20587 | The original breakthrough. 40 Hz light flicker reduced amyloid-beta plaques in mouse visual cortex by ~50% and activated microglia to clear toxic protein buildup. |
| 2019 | Martorell et al., Cell 177(2), 256-271. doi:10.1016/j.cell.2019.02.014 | Extended to auditory stimulation (the protocol this app replicates). 40 Hz sound reduced plaques in the hippocampus and prefrontal cortex. Mice showed improved memory task performance. |
| 2021 | He et al., Alzheimer's & Dementia: TRCI 7(1), e12178. doi:10.1002/trc2.12178 | Confirmed safety and tolerability of 40 Hz stimulation in human patients over extended periods. |
| 2022 | Chan et al., Journal of Internal Medicine 290(5), 993-1009. doi:10.1111/joim.13329 | Early human clinical data. Patients with mild Alzheimer's receiving daily 40 Hz audio-visual stimulation showed reduced brain atrophy and improved functional connectivity vs. controls. |
Cognito Therapeutics, an MIT spinoff, is conducting ongoing FDA-approved clinical trials with a dedicated device. This program replicates the auditory component of their protocol as closely as possible using standard PC audio hardware.
Disclaimer: This program is not a medical device and is not FDA-approved for the treatment of any condition. The research is promising but still in clinical trial stages. Consult a healthcare professional before using this as part of any health regimen.
- Language: C (C99)
- Audio: WASAPI shared mode -- 44.1 kHz, 32-bit float, stereo, event-driven; automatic
waveOut(16-bit) fallback if WASAPI init fails - Synthesis: Phase-accumulator sine generation, noise generators (white/pink/brown), 40 Hz pip train with trapezoidal envelope; all sample math in double precision, emitted as float
- GUI: Pure Win32 API (no manifest -- classic gray-bevel look)
- Threading: GUI thread + a dedicated WASAPI render thread (or
waveOutcallback thread in fallback);CRITICAL_SECTION-guarded parameter passing - Tests: 15 unit tests (10 synth, 5 preset) via
assert.h
Built with gcc (MinGW-w64) on Windows.