DUO Smart Noise Monitor

A Unique Sound Level Meter and Monitoring Station in One.

01dB introduces the new version of the DUO Smart Noise Monitor. Totally modular, DUO provides its users with the most complete offering to upgrade from sound-level meter to monitoring station without changing equipment.
Visually, DUO remains the same: a metallic profile allowing fast and secure anchoring, a rubber grip for better handling, a screen that is perfectly legible in direct sunlight, high quality finish. Similarly, it maintains its incredible innovations: the world's only waterproof microphone, weather-resistant build, integrated GPS and Wi-Fi/3G wireless connectivity, which is essential to be able to control the DUO remotely. DUO has obtained CEI-61672 Class-1 certification (for the two reference directions 0° and 90°) from Laboratoires LNE (France), PTB (Germany) and METAS (Switzerland). This demonstrates the attention given by 01dB to ensure DUO's metrological quality.
01dB injected all of its know-how into acoustic monitoring to develop over 50 new remarkable functions for the DUO. It has now become a veritable monitoring station: event detection expert module, new acoustic indicators, SMS operating alerts, interface with weather station…Sound-level meter or monitoring station, one choice: DUO 

For more information on the DUO Smart Noise Monitor, contact your local Air-Met office. 

01dB DUO Smart Noise Monitor Features Include:

DUO has innovative characteristics never before achieved by any producer in a single device:
  • Fully waterproof body
  • Metallic profile allowing quick and secure anchoring
  • Rubber grip for better handling
  • Colour screen perfectly legible in direct sunlight
  • 3-key pad for simplified operation
  • Waterproof microphone supplied exclusively by G.R.A.S.
  • Integrated Wi-Fi/3G modem for remote operation and automatic data retrieval
  • Integrated GPS antenna for precise localisation and synchronisation
  • Battery with operating time of 60 hours for simplified installation
  • Memory card of 2 to 128 GB for almost limitless storage.
  • DUO natively integrates several modules for communications with external terminals:
  • Direct USB connection
  • Ethernet network (RJ45 cable)
  • Point-to-pointWi-Fi network
  • 3G communication thanks to the Modem option (SIM card and subscription not included).
Users now no longer need to choose between two systems. DUO is the right choice every time.

01dB DUO Smart Noise Monitor Specifications Include:

Technical Specifications
IEC Class
IEC 61672-1 (2002-2005) (0° and 90°), class 1
IEC 61260 (1995) NF EN 61260/A1 (2002)
Dynamic Range
20-137 dB (A, B), 25-137 dB (C), 30-137 dB (Z),
1 single range for a rated sensitivity of 50 mV/Pa
(between 46 and 56mV/Pa)
Linear Operating Range for A Weighting (5
31,5 Hz: 20-97 dB
1 kHz: 20-137 dB
4 kHz: 20-137 dB
8 kHz: 20-133 dB
12,5 kHz: 20-129 dB
Dynamic Range Peak 60-140 dBC, 1 single range
Time Weightings Slow, Fast, Impulse, Peak
Instantaneous Weather Data Stored
Wind speed [m/s]
Wind direction [°]
Rain intensity [mm/h]
Barometric pressure [hPa]
Air temperature [°C]
Humidity [%HR]
Noise Logging Period T
Mini 20ms - maxi 3600s, 5 ms steps
Short logging period: mini 20ms – max standard T,
5 ms steps.
Short logging period applicable during events
Short logging period must be a divisor of T
Weather Logging Period
Weather logging period is a multiple of T with a
minimum of 1 second
Filters 1/1 (8Hz-16kHz) et 1/3 (6.3Hz-20kHz)
Back Erase 0, 5s or 10s, SLM mode only
Data Storage Modes
SLM (hand-held sound level meter) and LOG (logging sound level meter)
Audio Recording
Uncompressed metrological signal, Fs = 51200 Hz
Sampling frequencies: 51200, 25600, 12800, 6400, 3200, 1600 Hz
Pre-trigger = 10s at Fs=51200 Hz LEMO output connector
Immediate, differed, daily periodic
Audio: periodic
Integrated Keys
4 silent keys: on/stand-by/off and 3 multi-functions
Status Indicators
LED red (overload)
LED blue (Wi-Fi connection)
LED green (power ON, blinking on on-going
measurement, charge ON)
High contrast colour screen 38*50mm resolution
320*240 pixels
3 sets of colours (day, contrast, night)
Display rate: 0.1s, Display resolution: 0.1dB
USB Connection
Type 2.0; mass storage mode, charge on USB
Ethernet connection
Ethernet Connection
Connector RJ45, Speed: 100 MB/s
DHCP mode
GPS PPS, error < 50 ms
NTP Synchronisation
Internal clock drift < 0.5s/24h
Warm Up Time From power off: < 20 seconds
Operating Temperature -10°C to +50 °C
Humidity CEI 60068-2-78: damp heat 90% HR (none condensing at 40°C)
Electromagnetic Compatibility According to Directive 2004/108/EC
Protection IP55 mounted vertically with connectors cover
Weight and Dimensions 1100 g - H x L x P: 360 x70 x 52 mm


01dB DUO Smart Noise Monitor Applications Include:

  • Mobile or permanent noise monitoring station
  • Construction site monitoring
  • City monitoring
  • Race circuit monitoring
  • Wind farm monitoring
  • industrial plant monitoring
  • Airport noise monitoring
  • Neighbourhood noise
  • Industrial noise
  • Traffic noise
  • Leisure and recreation noise
  • Wind farm control
  • Vehicle noise
  • Sound insulation
  • Reverberation time
  • Room acoustic modelling
  • Occupational noise
  • Occupational vibration