01Pressure
Infrasound
Below approximately 20 HzSlow pressure fluctuations need dedicated sensing, wind-noise control, and a measured low-frequency response.
INDEPENDENT RESEARCH / NIGERIA
Open Frequency
Observatory.
Exploring the invisible soundscape.
CONCEPT & DEVELOPMENT
An open-source toolkit for detecting, visualizing, and investigating environmental acoustic signals and mechanical vibrations beyond ordinary human perception.
Explore the project ↘01 / SIGNAL EXPLORERSYNTHETIC SIGNAL
8 Hz1000 ms observation window
8 cycles per second. A dedicated low-frequency pressure sensor is needed to investigate this band.
Switch bands to explore frequency and time scale. This mathematical illustration makes no measurement, plays no sound, and does not represent sensor performance.
OPEN INSTRUMENTATIONACOUSTICS / VIBRATION / SIGNAL PROCESSINGPROJECT 001
01 / THE QUESTION
What happens beyond
what we can hear?
The environment is full of pressure fluctuations and mechanical motion. Human hearing reveals only part of it. Measuring the rest begins with the right sensor—and knowing its limits.
OFO aims to make that process easier to build, inspect, and reproduce. A shared software workflow will connect specialized sensors to understandable visualizations and documented recordings.
02Pressure
Ultrasound
Above approximately 20 kHzHigh-frequency acoustics need an ultrasonic microphone, sufficient sample rate, and anti-aliasing protection.
03Motion
Mechanical vibration
Sensor-dependent bandwidthAccelerometers and geophones measure motion in structures or the ground. Their readings are distinct from airborne sound.
02 / THE INSTRUMENT
Many sensors.
One inspectable workflow.
Instrumentation can be costly, fragmented, and difficult to integrate. We plan to connect existing hardware through modular adapters, with calibration and measurement limits carried alongside the data.
- 01SensePressure or motion
- 02ConditionGain & anti-aliasing
- 03DigitizeSample & timestamp
- 04AnalyzeSpectrum & events
- 05RecordRaw data & metadata
Planned capabilities
- Waveform, FFT & spectrogram
- Device selection & sensor adapters
- Band filters & event timestamps
- WAV / CSV exports & data logging
- Calibration & noise-floor metadata
- Frequency translation for exploration
These are proposed toolkit features. Frequency translation produces an audible representation; it does not make the original inaudible signal directly audible.
03 / MEASUREMENT BEFORE INTERPRETATION
Start with what
we can verify.
The first development setup uses an Aston Origin microphone and Behringer UMC22 audio interface. It can support audible-band experiments and software development.
It is not a calibrated infrasound or ultrasonic measurement system. A sample-rate limit is not a guarantee of usable sensor bandwidth.
Research directions
Atmospheric acoustics, environmental sound, structural vibration, and ultrasonic activity are candidate applications.
Environmental correlations come later, once measurements have known response, timing, and uncertainty. Correlation alone cannot identify a source or establish causation.
Human-response studies, medical claims, and cosmic explanations are outside the initial instrumentation phase.
04 / DEVELOPMENT ROADMAP
A small, testable first phase.
A proposed schedule, dependent on funding, supplier availability, and validation. No specialized sensors or validated datasets are claimed as complete.
NOW → NOV 2026
Define & demonstrate
Publish the project brief; prepare the grant application; develop an audible-band demonstration with existing audio equipment.
JAN → MAR 2027
Acquire & characterize
Subject to funding: obtain one pressure-sensing chain, verify acquisition, and document response, timing, noise, and limitations.
APR → JUN 2027
Integrate & reproduce
Integrate a second sensor modality; release a versioned analysis prototype and reproducible bench tests. Report within two months of funding, no later than June 15.
JUL → NOV 2027
Share & evaluate
Publish documented example recordings and build guides; invite independent reproduction and share lessons learned. Final report by November 15.
05 / BUILT TO BE REPRODUCED
An instrument you
can learn from.
For independent makers, students, engineers, and researchers: the intended output is a usable instrument and a transparent account of how it works.
The analyzer prototype is public: a local-first signal acquisition and analysis application with tested DSP, hardware validation evidence, and a test report, under the MIT license. View the repository ↗
Future releases will add sensor integration notes, calibration procedures, annotated example recordings, and practical tutorials.
Read the proposed technical brief
A local-first Python processing engine will separate acquisition, analysis, and storage. NumPy and SciPy are proposed for DSP; sensor adapters will expose sample rate, units, timing, calibration state, and data-loss flags. Raw recordings remain separate from filtered or translated derivatives.
Initial validation will use synthetic test signals and repeatable bench recordings. Uncalibrated audio will be displayed in digital units, not absolute sound-pressure levels. Sensor-specific validation must precede environmental interpretation.
06 / THE INITIATOR
Engineering meets
the recording studio.
I’m OVD, a Mechanical Engineering graduate of the University of Benin, Nigeria, a full-stack and blockchain developer, and a music producer and audio engineer.
OFO brings together an understanding of physical vibration, software development, and practical work with microphones, recording, EQ, and digital audio. It extends my interest in sound from creative production into scientific measurement.
This is an independent project. No university partnership or institutional endorsement is claimed.
Explore my work ↗Music & production ↗Help build an open
window into the soundscape.
Seeking support for initial instrumentation, testing, and reproducible community tools. Preparing an application to the Hacker Initiative 2026 grant cycle; funding has not been awarded.
Discuss OFO ↗