Sub-Bass Frequency Detector
Specialized detector for frequencies from 1–100 Hz. Identify low-frequency rumble, HVAC hum, traffic noise, appliance vibration, and other sub-bass sources. Features source matching, vibration threshold indicator, health advisory, and event logging.
Sub-Bass Frequency Detector Tool
Prolonged exposure to low-frequency noise (<100 Hz) at high levels can cause fatigue, headaches, difficulty concentrating, and sleep disruption. If you consistently detect strong sub-bass noise in your environment, consider consulting an acoustics professional.
| Source | Frequency | Notes |
|---|---|---|
| Wind turbines | 1–5 Hz | Infrasound, felt not heard |
| Earthquakes | 1–10 Hz | Seismic infrasound |
| Thunder | 1–3 Hz | Low rumble component |
| Diesel engine idle | 20–30 Hz | Heavy vehicles, generators |
| Traffic rumble | 25–40 Hz | Road and bridge vibration |
| Washing machine | 30–45 Hz | Spin cycle vibration |
| HVAC compressor | 40–60 Hz | Air conditioning unit |
| Refrigerator | 40–50 Hz | Compressor hum |
| Mains hum (EU) | 50 Hz | Electrical interference |
| Mains hum (US) | 60 Hz | Electrical interference |
| Subwoofer bass | 20–80 Hz | Music/movie sub-bass |
| Kick drum | 50–100 Hz | Fundamental frequency |
| Time | Peak Hz | Level dB | Likely Source |
|---|
Drag & drop an audio file here or click to browse
Supports WAV, MP3, OGG, FLAC, M4A, AAC, WebM
How to Use the Sub-Bass Frequency Detector
Start Listening
Click "Start Listening" and grant microphone access. For best sub-bass detection, use an external microphone or audio interface — built-in laptop mics often filter out frequencies below 80 Hz.
Read the Sub-Bass Display
The large Hz number shows the strongest frequency in the 1–100 Hz range. The perception threshold bar shows whether the frequency is in the "feel" zone (infrasound), "hear" zone, or normal bass range.
Check Source Identification
The Source Identification card matches the detected frequency against a database of common low-frequency sources (HVAC, traffic, appliances) and suggests the likely cause.
Monitor Over Time
The Energy Over Time chart tracks sub-bass energy across 30 seconds. The Rumble Event Log records significant events with timestamps for evidence collection.
Export Evidence
Use 💾 Export CSV to download your event log for noise complaint documentation or analysis.
How Sub-Bass Detection Works
Detecting very low frequencies requires special considerations compared to standard audio analysis.
Large FFT for Fine Resolution
This tool uses an FFT size of 16,384 samples to achieve frequency resolution of ~1.5–3 Hz per bin at 48 kHz sample rate. Standard FFT sizes (2,048 or 4,096) have bins too wide (12–24 Hz) to distinguish between different sub-bass sources.
Focused Sub-Bass Analysis
Rather than analyzing the full 0–24 kHz spectrum, this tool focuses exclusively on FFT bins corresponding to 1–100 Hz. This allows detailed visualization and accurate peak detection in the sub-bass range without being overwhelmed by higher-frequency content.
Microphone Limitations
Most consumer microphones have a high-pass filter that attenuates frequencies below 80–100 Hz. Professional condenser microphones and measurement microphones extend to 20 Hz or below. The tool shows a warning when sub-bass detection may be limited by your hardware.
Source Matching
The source identification system compares the detected peak frequency against a lookup table of known sub-bass sources with their characteristic frequency ranges. Multiple sources may overlap, and the system picks the closest match.
Frequently Asked Questions
Why can't I detect frequencies below 50 Hz?
Most built-in laptop and phone microphones have a high-pass filter that removes frequencies below 80–100 Hz. To detect true sub-bass, you need an external condenser microphone, USB audio interface, or measurement microphone designed for low-frequency capture.
Is low-frequency noise harmful to health?
Prolonged exposure to low-frequency noise at high levels (above 70–80 dB) can cause fatigue, headaches, difficulty concentrating, and sleep disruption. Very intense infrasound (<20 Hz) can cause nausea and disorientation. If you experience persistent symptoms, consult an occupational health specialist.
What causes a persistent low-frequency hum in my house?
Common causes include HVAC compressors (40–60 Hz), refrigerator compressors (40–50 Hz), nearby traffic (25–40 Hz), electrical transformers, and water pumps. This tool can help identify the exact frequency, which narrows down the source.
What is the difference between sub-bass and infrasound?
Sub-bass generally refers to 20–60 Hz — the lowest audible frequencies. Infrasound is below 20 Hz and is typically felt as vibration rather than heard as sound. Both are covered by this detector.
Can I use this to document a noise complaint?
Yes. The Rumble Event Log records significant sub-bass events with timestamps, frequencies, and levels. Export the CSV to include with a noise complaint. Note that for legal purposes, certified measurement equipment may be required.
Is my audio data safe?
All processing runs 100% in your browser. No audio is recorded, stored, or transmitted. The tool works offline once loaded.