FreqCheck : See Sound

From 0.2 Hz infrasound detection to 96kHz wideband acoustics. FreqCheck is the Class 1 Mobile Lab App with ISO/IEC 17025-calibrated, NIST-traceable data. No bench needed.

Identify sources, audit content, or import lab audio files.

FreqCheck is the first and only Class 1 Mobile Lab App — an ISO/IEC 17025-calibrated, NIST-traceable spectral engine powered by IND CORE™ (U.S. Patent No. 12,659,418) that adapts to your expertise.

From 0.2 Hz infrasound detection to 96 kHz tactical WideBand acoustics, FreqCheck transforms your iOS device into an enterprise-grade measurement laboratory.

You've heard it. That low, persistent hum no one else seems to notice. That frequency track promising precise therapeutic tones. That high-speed transient acoustic event or vibration in your chest you cannot explain.

It doesn't matter what you were told — FreqCheck lets you measure and prove it.

ENTERPRISE METROLOGY. ONE SEAMLESS APP.

FreqCheck houses everyday scanning, raw Pro Input Mode (PIM), and dedicated Tactical Wideband Metrology in a single certified engine.

Direct DC-coupled Line-In integration connects to professional DAQ hardware and external instrumentation microphones with zero attenuation, scaling instantly from your iPhone microphone to raw lab captures up to 192 kHz sample rates.

PRO INPUT MODE (PIM):

PIM grants direct manual control over critical hardware variables — dedicated input channel selection (Left, Right, Auto), sample rate locks, ADC voltage ceilings, and sensor sensitivity coefficients (mV/Pa) — bypassing standard mobile audio filters and auto-gain compression entirely. Built-in dual preset slots allow you to save and instantly recall custom hardware profiles in the field for repeatable, sub-Hz precision.

TACTICAL WIDEBAND METROLOGY:

Engineered for high-frequency acoustic analysis, ballistic impulse testing, and WideBand telemetry up to 96 kHz (192.0 kHz sampling). Features high-contrast digital SPL readouts, real-time Live SPL tracking, instant Peak Hold (Max SPL) capture, and full uncompressed laboratory spectral telemetry.

OFFLINE MEDIA AUDITING:

Natively ingest raw video and lossless audio formats (.wav, .flac, .alac, .aiff, .m4a, .mp3), applying calibrated metrology math to pre-recorded files completely offline. Audit digital media claims, verify sound therapy tracks, and conduct deep forensic signal analysis.

FORENSIC-GRADE PROOF. IN YOUR POCKET.

Measurements are anchored by a four-layer forensic security protocol: device-hash anchoring, real-time SHA-256 frame sealing, session hashing, and digitally signed PDF Audit Reports. Any attempt to alter telemetry breaks the seal and invalidates the document.

Present data with full laboratory evidentiary weight. ISO/IEC 17025:2017 Calibrated (Cert #05122C9A 2602).

ZERO-KNOWLEDGE PRIVACY

100% of IND CORE™ processing happens locally on your device via edge computing. No raw audio or video is ever uploaded or stored. Your telemetry stays strictly with you.

Starter: Free basic scans, ad-supported.

Remove Ads: $2.99 one-time.

*Pro Analyst Monthly: $19.99/month, 7-day free trial.

*Pro Analyst Lifetime: $149.99 one-time.

*Pro unlocks the LOGS vault, full ISO-compliant PDF Audit Reports, and posting and commenting in the Nyquist Forum — a growing repository where field teams and investigators share certified, sealed telemetry data.

THE MICROSCOPE MOMENT

The microscope didn't create bacteria. It revealed what was always there.

GPS didn't create your location. It made it knowable.

FreqCheck makes the entire spectrum — from deep infrasound to high-speed WideBand acoustics — visible, measurable, and provable.

You don't need a degree. You need one tap.

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DISCLAIMER: Engineered metrology tool for research, acoustic consulting, and educational purposes only. Not intended for medical diagnosis. Full end-to-end NIST traceability requires an unbroken chain of calibrated external hardware.