ARC SHIELD FIELD GUIDE

ACOUSTIC MONITOR · HEARING GUARD · EVIDENCE RECORDER - FIELD MANUAL

"No weapon formed against thee shall prosper, and every tongue that shall rise against thee in judgment thou shalt condemn." - Isaiah 54:17

1. HOW ARC SHIELD WORKS

ARC Shield turns a phone, tablet or laptop into three instruments: an acoustic monitor, a hearing guard and an evidence recorder. It uses the Web Audio API built into every modern browser. Everything runs on the device; no audio, reading or location is sent anywhere.

1.1 DETECTION: A MONITOR THAT CAN SAY CLEAR

For its first five seconds it learns the room: the normal spectrum of that place. After that it reports only tones that stand out - at least 14 dB above their neighbouring frequencies and 8 dB above the room - and only once they persist. A detector that calls every fridge a weapon is useless as evidence, so each tone is classified with the ordinary explanations first:

Mains hum - exactly 50 or 60 Hz or a multiple: transformers, lights, chargers. Benign.
Alarm pattern - repeating beeps around 3 kHz (or 520 Hz): smoke and CO alarms. Benign.
Sweeping tone - gliding up and down: sirens; some hailing devices also have a siren mode.
Near-ultrasonic tone - 16.5 kHz and up: electronics whine, pest repellers, anti-loitering devices, app tracking beacons.
Loud sustained tone, 1-5 kHz - consistent with an acoustic hailing device (LRAD-type), and also with sirens, horns and alarms. Flagged only when it is loud.
Steady or low-frequency tone - fans, engines, HVAC, music. Listed, not flagged.

The status line reads CLEAR, UNUSUAL TONE, LOUD TONE, LOUD or PROTECT YOUR HEARING. It tells you what a sound is consistent with. It never names a device, because a microphone cannot.

1.2 HEARING GUARD: LEVEL AND DOSE

The meter shows the A-weighted level (how the ear weights loudness), the average since you started, and the maximum. If the sound overloads the microphone - louder than the phone can measure - the screen switches to PROTECT YOUR HEARING with three steps, and the phone vibrates. Once calibrated (1.4), it also keeps a running noise dose against the NIOSH limit (85 dBA for eight hours, halving with every 3 dB more) and shows how long you have left at the current level.

1.3 EVIDENCE CAPTURE

RECORD saves a single ZIP containing:

the audio as lossless WAV, including the 30 seconds before you pressed record;
the spectrogram as an image;
every tone the monitor classified, as a spreadsheet (CSV);
a manifest: start and end times (UTC), the microphone settings the browser actually applied, calibration, your location if you logged it, and levels during the recording;
SHA256SUMS - a fingerprint of every file - and a README.

Run sha256sum -c SHA256SUMS in the unzipped folder and every line should say OK; that is how anyone can later confirm nothing was changed. Send the SHA256SUMS file to yourself or someone you trust as soon as you can, so the fingerprints exist somewhere outside the phone. AUTO-CAPTURE starts a recording by itself when a loud tone or overload appears, and stops 30 seconds after it ends.

1.4 SELF-TEST AND CALIBRATION

SELF-TEST plays short tones through the phone's own speaker, from 1 kHz upward, and reports which ones its microphone heard - so you know this phone's real upper limit before you rely on it. It also shows whether the browser switched off its voice processing (echo cancellation, noise suppression, auto gain), which matters for evidence.

CALIBRATE: phones measure relative to their own maximum (dBFS), not in decibels of sound pressure. Hold the phone beside a calibrated sound level meter in steady noise, type the meter's dBA reading, and ARC Shield stores the offset on that device. A calibrated phone is a good screening meter, not a certified one; say so if you use its numbers.

1.5 WHAT IT CANNOT DO, AND WHY

It cannot cancel or block a sound from outside. Cancellation needs an inverted copy of the wave matched in level and timing at one point - which is why it works inside headphones, where the microphone and the ear are millimetres apart. A phone speaker in open air cannot match a hailing device's output, and a second tone in the same band adds sound rather than removing it. Earlier versions offered "cancellation" and "jamming" modes; they are gone for that reason.
It cannot hear infrasound (below 20 Hz) - phone microphones roll off far above that - and it cannot hear above half its sampling rate (about 22-24 kHz). Run SELF-TEST to see your phone's limit.
It cannot identify a device. It says what a sound is consistent with and what else it could be.

The tone sessions that used to sit in ARC Shield (Schumann, solfeggio and others) are at /tones/healing. ARC Shield keeps pink and brown comfort noise for headphones, capped in volume: it masks sound, it does not block it.

2. WHAT IS LRAD & ACOUSTIC WEAPONRY

LRAD (Long Range Acoustic Device) is a flat-panel speaker array made by Genasys (formerly LRAD Corporation). It projects voice and tones in a narrow beam. Police use it both as a loudspeaker and, in some deployments, for its "deterrent tone".

Manufacturer figures (Genasys datasheets)

LRAD 2000X: maximum continuous output 160 dB SPL at 1 m (A-weighted); maximum peak 168 dB SPL at 1 m (C-weighted). Smaller models run from 137 dBA continuous (100X) upward.
Beam: ±15° at 1 kHz (−3 dB points) - about 30° wide; lower frequencies spread wider.
Range: voice "up to 5,500 meters in ideal conditions"; the manufacturer's own warning, quoted by the Second Circuit, sets a danger zone within 10 m.
Frequency: the sheets give no tone frequency; an earlier brochure gives 200 Hz to 10 kHz overall. ARC Shield watches 1-5 kHz because that is where a loud warning tone is most likely to sit, not because a datasheet says so.

In open air the level falls about 6 dB with each doubling of distance (beyond the device's roughly 8 m near field). For the 2000X that is about 140 dB at 10 m, 120 at 100 m and 100 at 1 km - before wind, ground and air absorption. A phone microphone cannot measure most of that range; most top out around 100 dB.

What courts and cities have recorded

Edrei v. Maguire, 892 F.3d 525 (2d Cir. 2018): "purposefully using a LRAD in a manner capable of causing serious injury to move non-violent protesters to the sidewalks violates the Fourteenth Amendment under clearly established law." New York City settled in April 2021 for $748,000, banned the deterrent tone and adopted a written LRAD policy, without conceding wrongdoing.
Pittsburgh, G-20 (2009): the city paid $72,000 in 2012 to a visiting professor who reported permanent hearing loss after police used an LRAD on a residential street, and agreed to draft a deployment policy. It admitted no wrongdoing.
Reported uses: Ferguson 2014 (Slate), Standing Rock 2016 (Mother Jones) and Portland 2020 (OPB; the Portland Police Bureau confirmed using its LRAD).

Related claims, at the tier the record supports

Microwave auditory effect: real physics (pulsed RF heard as clicks or sound). US Patent 6,470,214 (O'Loughlin & Loree, US Air Force, 2002), "Method and device for implementing the radio frequency hearing effect", describes carrying speech this way. A phone microphone cannot detect it - the effect happens inside the head, not in the air.
MEDUSA: a Navy small-business (SBIR) project by WaveBand Corporation, 2003-04, later acquired by Sierra Nevada Corp. Not a DARPA program; fielding and effectiveness are undocumented.
"Havana Syndrome": not an LRAD matter. US intelligence agencies assessed in 2023, and most again in January 2025, that a foreign adversary is "very unlikely" to be responsible; one agency dissented in 2025. NIH studies (2024) found no MRI-detectable brain injury.
The "Mosquito": a commercial anti-loitering device with a setting around 17.4-17.5 kHz, audible mainly to young people, rated by its maker at up to 108 dB.
Audio beacons: in March 2016 the FTC warned 12 app developers whose apps contained SilverPush code that listens for inaudible codes in TV audio.

3. SETUP & INSTALLATION

3.1 INSTALL AS APP (PWA)

The ARC Shield is a Progressive Web App (PWA). You can install it from any browser - no app store, no account, no tracking. Once open it runs without a connection; opening it again needs one.

Android (Chrome / Edge / Brave / Firefox)

Go to b0b.dev/tones/shield in your browser
Tap the three-dot menu (top right)
Select "Add to Home Screen" or "Install App"
Confirm the installation
The ARC Shield icon appears on your home screen - opens fullscreen, no browser chrome

iPhone / iPad (Safari)

Open b0b.dev/tones/shield in Safari (other browsers cannot install PWAs on iOS)
Tap the Share button (square with arrow, bottom center)
Scroll down and tap "Add to Home Screen"
Tap "Add"

Desktop (Chrome / Edge / Brave)

Navigate to b0b.dev/tones/shield
Click the install icon in the address bar (or the install banner if shown)
Runs as a standalone window

3.2 AN OLD PHONE AS A DEDICATED RECORDER

Why Old Phones Are Perfect For This

Any old Android or iPhone that still powers on and connects to WiFi is a ready-made acoustic defense device. You don't need cell service, a SIM card, or an active plan. The phone already has a microphone, speaker, processor, and battery - everything the ARC Shield needs.

Android (5.0+)

Factory reset the phone (Settings > System > Reset) to clear old data and maximize performance
Connect to WiFi - you only need internet once to load the page
Open Chrome and go to b0b.dev/tones/shield
Install as PWA (see 3.1 above)
Grant microphone permission when prompted
Enable Developer Options (Settings > About Phone > tap Build Number 7 times):
- Turn on "Stay Awake" (screen stays on while charging)
- Optional: "Force GPU Rendering" for smoother spectrogram
Lock to ARC Shield using Screen Pinning:
- Settings > Security > Screen Pinning > ON
- Open ARC Shield, tap Recents, tap the pin icon
- The phone is now locked to ARC Shield - cannot accidentally close it
Disable notifications (Settings > Apps > disable all non-essential notifications)
Set volume to maximum

iPhone (iOS 14+)

Erase the iPhone (Settings > General > Transfer or Reset > Erase All Content)
Set up as new - skip Apple ID if you don't want cloud features
Connect to WiFi
Open Safari, go to b0b.dev/tones/shield
Add to Home Screen
Enable Guided Access (Settings > Accessibility > Guided Access > ON):
- Open ARC Shield from home screen
- Triple-click Side button to start Guided Access
- Set a passcode - the phone is now locked to ARC Shield
Turn off Auto-Lock (Settings > Display > Auto-Lock > Never)
Set volume to maximum

Optimal Old Phone Models (Best Microphone Quality)

Samsung Galaxy S7-S9: Excellent MEMS microphones, strong bass response
Google Pixel 2-4: Outstanding mic quality (designed for Google Assistant)
iPhone 6S-8: Reliable, well-calibrated mics, long battery
OnePlus 5-7: Good speakers and mics, fast processors
LG V20-V40: Hi-fi DAC and quad mics - best audio hardware in any phone

3.4 TROUBLESHOOTING: MICROPHONE ACCESS

Desktop Browsers (Chrome / Edge / Brave)

Desktop browsers enforce microphone permissions more strictly than mobile browsers. If the ARC Shield is not prompting for mic access on desktop:

HTTPS Required: Microphone access is only available over HTTPS. Make sure you are accessing b0b.dev, not an insecure URL.
Check Site Permissions: Click the lock/tune icon in the address bar > Site Settings > Microphone. Set to Allow.
Clear Blocked State: If you previously denied mic access, the browser remembers. Go to Settings > Privacy & Security > Site Settings > Microphone. Find b0b.dev and remove it from the Blocked list, then reload.
Browser Permissions-Policy: The server must send the correct Permissions-Policy: microphone=(self) header. This was fixed in the latest deployment - if you still have issues, hard-refresh with Ctrl+Shift+R.
System Microphone: Ensure your OS allows the browser to access the microphone (Windows: Settings > Privacy > Microphone > allow desktop apps).

Mobile Browsers

Mobile browsers (especially Chrome on Android and Safari on iOS) are generally more lenient with microphone prompting. If mic access still fails:

iOS Safari: Go to Settings > Safari > Microphone > set to Ask or Allow
Android Chrome: Site Settings > Microphone > ensure b0b.dev is allowed
PWA: If installed as a PWA, microphone permission is set at install time. Uninstall and reinstall if needed.

4. IN THE FIELD

4.1 PROTECT YOURSELF FIRST

If a sound hurts, it is already too loud. Protect first, identify later.

Hearing protection. Foam earplugs, rolled thin and fully inserted; earmuffs over them for very loud sound. Carry a pair.
Know its limit. Earmuffs over earplugs add only 5-10 dB over one alone, and NIOSH calls even double protection inadequate above 105 dBA. Close to a hailing device, distance and cover do more than anything you wear.
Leave the beam. Hailing devices are strongly directional. Moving sideways out of the line they point along cuts the level faster than walking straight back.
Distance. In open air, each doubling of distance cuts the level by about 6 dB.
Hard cover. A building corner, a wall or a vehicle between you and the source.
Nothing else? Turn away and press your palms flat over your ears.
Afterwards: ringing, pain, a blocked feeling or dizziness should be seen by a doctor or audiologist. Keep the evidence file.

4.2 PERSONAL CARRY

Before you need it: open ARC Shield, press START so it learns a normal room, run SELF-TEST once, and turn on AUTO-CAPTURE. Log your location when you arrive. Keep the phone in a chest pocket or hand with the microphone uncovered - fabric over the microphone lowers every reading. Your hearing protection goes in first; the phone records.

4.3 SEVERAL PHONES, SEVERAL RECORDS

Phones at different places record the same event from different positions, and the differences in level between them help show where a sound came from and how far it carried. Each phone makes its own fingerprinted ZIP; nothing needs to be linked. An old phone (3.2) left recording on a balcony or in a car is a second, independent record of the same time.

5. OTHER USES & APPLICATIONS

Beyond LRAD Defense

Acoustic surveillance detection: The spectrogram detects ultrasonic tracking beacons (SilverPush, Shopkick) in the 18-22 kHz range used for cross-device tracking by advertisers
Environmental noise analysis: Identify sources of harmful noise pollution - construction, industrial equipment, HVAC systems - with frequency and dB documentation
Tinnitus masking: The protective frequency and noise generators provide customizable tinnitus relief
Meditation and grounding: Schumann resonance, Solfeggio frequencies and binaural entrainment for prayer, meditation and centering - at /tones/healing
Sleep protection: Run on an old phone at night. Brown noise masks environmental sound; the detection system alerts if anomalous acoustic signatures appear
Hearing protection monitoring: Use the dB meter and detection system to alert workers when sound levels exceed OSHA limits (85 dB over 8 hours)
Wildlife protection: Detect illegal ultrasonic deer/pest deterrents or acoustic harassment devices targeting animals
Building acoustic analysis: Map room resonances, identify transmission paths, locate hidden speakers or emitters
Musical tuning reference: The precise oscillators serve as frequency references for instrument tuning and acoustic measurement
Paranormal investigation tool: Infrasonic detection (100-300 Hz range) - standing waves at 18.98 Hz have been documented to cause visual anomalies and feelings of unease (Vic Tandy, 1998, "The Ghost in the Machine")

6. IMPROVEMENT ROADMAP

6.1 KNOWN ACOUSTIC DEVICES AND WHAT ARC SHIELD SEES

Hailing devices (LRAD-type): loud voice and tones, strongly directional. ARC Shield flags loud sustained tones at 1-5 kHz and overload; it lists sirens, horns and alarms as alternatives every time.
Anti-loitering devices: about 17.4 kHz or 8 kHz. Seen as a near-ultrasonic tone if the phone can hear that high (run SELF-TEST).
Audio beacons: inaudible codes in TV or shop audio, picked up by apps. Seen as near-ultrasonic tones on capable phones.
Infrasound and RF effects: outside what any phone microphone can measure. ARC Shield says so instead of guessing.

6.2 PUBLIC RECORD WORTH READING

NIOSH, Criteria for a Recommended Standard: Occupational Noise Exposure (98-126): the 85 dBA / 3-dB rule ARC Shield's dose uses; double protection adds "only 5 to 10 dB" and is "inadequate" above 105 dBA.
Kardous & Shaw, JASA 135(4) EL186 (2014): the best phone sound-meter apps came within 2 dB of a reference meter between 65 and 95 dB; Android devices varied widely. The NIOSH SLM app states ±2 dBA.
National Academies (2020) considered directed pulsed RF energy among plausible mechanisms for the embassy illnesses and said it "cannot rule out other possible mechanisms"; read it beside the ODNI assessments of 2023 and 2025.
Records to request: a police department's LRAD deployment policy, training records, use logs for a date, and purchase records. The NYC and Pittsburgh settlements both produced written policies - ask for them by name.

6.3 ANCIENT ACOUSTIC KNOWLEDGE

Ancient Civilizations Knew About Acoustic Resonance

Modern acoustic weapons exploit the same physical principles that ancient civilizations used for healing, protection, and spiritual practice. This is not speculation - these are measurable acoustic phenomena documented in archaeological studies.

Solfeggio Scale (Gregorian, pre-11th century):

The original six-tone scale: UT=396, RE=417, MI=528, FA=639, SOL=741, LA=852 Hz
Rediscovered by Dr. Joseph Puleo through analysis of the Book of Numbers (numerological patterns in the Latin Vulgate)
528 Hz is claimed to repair damaged DNA, citing Glen Rein (1998) - an unreplicated, non-peer-reviewed claim; no laboratory practice uses it
These frequencies appear in the ARC Shield's protective section

Tibetan Singing Bowls (2500+ years):

Produce rich harmonic overtones spanning 100-8000+ Hz
Traditional bowls are tuned to 136.1 Hz (Cosmic Om) - the Earth year frequency
The multi-harmonic output creates natural interference patterns similar to the ARC Shield's detune field
Research shows singing bowls reduce heart rate, blood pressure, and stress hormones (Goldsby et al., 2017)

Megalithic Architecture (5000+ years):

Newgrange, Ireland (3200 BC): Internal chambers resonate at 110 Hz - precisely the frequency shown to shift brain activity from left to right hemisphere dominance (UCLA study, 2008)
Hypogeum of Hal-Saflieni, Malta (4000 BC): Oracle chamber resonates at 110 Hz across multiple harmonics. Sound produced at the oracle niche fills the entire chamber through standing wave resonance.
Great Pyramid, Giza: King's Chamber resonates at 438 Hz (close to A=432 Hz). The chamber dimensions create standing waves at specific frequencies - this is precision acoustic engineering.
Stonehenge: The sarsen stones reflect and focus sound. Acoustic analysis shows it functions as an amphitheater that amplifies and contains sound energy within the circle.

Didgeridoo (40,000+ years):

Aboriginal Australian instrument producing fundamental drone at 50-80 Hz with rich harmonic overtone series
Circular breathing technique creates continuous sound - exactly the sustained tone generation the ARC Shield replicates digitally
The fundamental frequency range matches the ARC Shield's sub-harmonic grounding engine

Gregorian Chant (6th century+):

Monks chanting in stone chambers exploit room resonance to amplify specific frequencies
Dr. Alfred Tomatis documented that Gregorian chant energizes the brain through specific frequency stimulation ("The Ear and the Voice")
The "missing" fundamental effect in chant allows the brain to perceive frequencies the voice does not produce

The Jericho Principle (Joshua 6):

Seven priests with seven trumpets (shofars) circling city walls for seven days, combined with unified shouting
From an acoustic physics perspective: multiple coherent sound sources at specific positions around a structure create reinforcing standing waves. At resonant frequencies, these can amplify to destructive levels - this is documented structural resonance.
The shofar produces fundamentals at 200-500 Hz with powerful harmonics - a natural broadband acoustic weapon
The principle is reversed in the ARC Shield: instead of destroying walls, we create counter-resonance to defend people

6.4 TECHNICAL NOTES (VERSION 2.0)

Room baseline and persistence: a tone must stand 14 dB above its neighbours and 8 dB above the learned room, and be present most of the time, before it is reported.
Benign-first classification: mains, alarm, siren, near-ultrasonic, loud 1-5 kHz, low, steady.
Level: IEC 61672 A-weighting applied to the spectrum, fast (125 ms) time weighting, Leq, max, clipping detection; NIOSH dose once calibrated.
Evidence: raw capture through an AudioWorklet, 30 s rolling pre-roll, 16-bit WAV, ZIP with SHA-256 for every file.
Tested both ways: scripts/arc-selftest.js proves a quiet room, mains hum and alarm bursts stay benign while loud tones, near-ultrasound, sirens and overload are raised.
Removed: auto-cancel, sweep jam, broadband, pulse counter and the counter-frequency engine - none could reduce an outside sound.

7. REFERENCES & SOURCES

Standards and agencies

NIOSH, Criteria for a Recommended Standard: Occupational Noise Exposure, Revised Criteria 1998 (DHHS/NIOSH 98-126)

OSHA, 29 CFR 1910.95, Occupational noise exposure (Table G-16)

NIOSH Sound Level Meter app documentation (cdc.gov/niosh/noise)

ODNI, Intelligence Community Assessment on Anomalous Health Incidents, 1 March 2023; update, 10 January 2025

National Academies of Sciences, Engineering, and Medicine, An Assessment of Illness in U.S. Government Employees and Their Families at Overseas Embassies (2020)

FTC, "FTC Issues Warning Letters to App Developers Using 'Silverpush' Code", 17 March 2016

Courts and settlements

Edrei v. Maguire, 892 F.3d 525 (2d Cir. 2018); NYC settlement, April 2021 (Gothamist, 19 Apr 2021)

ACLU of Pennsylvania, Pittsburgh G-20 settlements, 14 Nov 2012

Manufacturer

Genasys, LRAD 2000X / 1000Xi / 500X-RE / 450XL / 100X product datasheets

Patents

US 6,470,214 B1, "Method and device for implementing the radio frequency hearing effect", O'Loughlin & Loree, US Air Force, 2002

US 6,587,729 B2, "Apparatus for audibly communicating speech using the radio frequency hearing effect", same inventors and assignee

Research

Kardous, C.A. & Shaw, P.B., "Evaluation of smartphone sound measurement applications", J. Acoust. Soc. Am. 135(4), EL186 (2014)

Reporting

Slate, 14 Aug 2014 (Ferguson); Mother Jones, 31 Oct 2016 (Standing Rock); OPB, 5 Jun 2020 (Portland)

The fact-check behind this guide, with every quote and the sources that refused the crawler, is kept with the site's research files (ARC-SHIELD-FACTS.md).