Measure Low-Frequency Hum & Noise (Rent, Buy & On-Site Service)
Heat pumps, HVAC systems, transformers, or unknown low-frequency hum: Standard-compliant measurement and long-term monitoring per DIN 45680.
- Captures deep low-frequency tones (8 Hz to 100 Hz) that standard A-weighted meters filter out
- Available as rental kit for self-measurement (100% purchase credit), purchase system, or on-site engineering service
- Our 6 dB(A) ultra-low-noise system resolves faint hums even near the threshold of hearing
Available Versions & Services
Current prices from Dresden stock / lab
EDU Rental Complete Audio Measurement System for environmental mesurements
Weekly rental complete USB audio measurement system for environmental, low-frequency, and neighborhood noise.
Complete Audio Measurement System for environmental mesurements
Complete USB audio measurement system incl. precision USB measurement microphone and analysis software.
Measurement low noise
On-site low-frequency hum investigation by our acoustic engineers using ultra-low-noise equipment incl. report.
3-Step Procedure
1. Choose Your Path
Rent our USB environmental measurement system (Art. 1202m) or inquire about our on-site hum investigation (DBrumm).
2. Day & Night Logging
Record time history, 1/3-octave spectra (LCeq - LAeq), and raw audio continuously.
3. DIN 45680 Evaluation
Narrowband FFT and 1/3-octave analysis pinpoint the exact offending source.
Why Standard Sound Meters Fail on Low-Frequency Hum (A-Weighting & Self-Noise)
Click to expand technical details and standard references
Why Standard Sound Meters Fail on Low-Frequency Hum (A-Weighting & Self-Noise)
Click to expand technical details and standard references
When measuring low-frequency hum (e.g. heat pumps, transformers, or HVAC systems between 50 Hz and 100 Hz), two physical obstacles occur at once: First, standard A-weighting (dB(A)) attenuates a 50 Hz tone by 30.2 dB. Therefore, DIN 45680 mandates comparing C- and A-weighted levels (LCeq minus LAeq > 20 dB) alongside 1/3-octave analysis from 8 Hz to 100 Hz.
Second, basic 1/4-inch microphones have a self-noise floor around 30 dB(A), completely masking a 22 dB nighttime hum. Our environmental measurement kit (Art. 1202m / 1202) uses a low-noise 1/2-inch capsule, and our on-site engineering service (Art. DBrumm) deploys a G.R.A.S. 40HL reference microphone with a 5.5 dB(A) noise floor.
Tested Lab Quality & 24-Month B2B Warranty
Every new and certified refurbished unit passes our quality inspection routine in Dresden prior to delivery. Individual factory calibration certificates for ISO 9001 audits are available upon request.