Wireless sound level meter data logger type 1 NSRTW_mk2 (THIS PRODUCT IS END OF LINE AND REPLACED BY NSRTW_mk3)

Product Description

The Wireless Sound Level Meter Data Logger NSRTW_mk2 is the second generation of Convergence Instrument’s WiFi™ enabled smart integrating sound-level meter/datalogger. It includes a type 1 digital MEMS microphone, an accurate date/time clock, a non-volatile 128 Mb recording memory and wireless connectivity with fast USB and WiFi download.

Running on battery, it can record sound pressure levels and report them through WiFi™ for a week. Connected to an external USB charger it can record and report for months. Its very small size allows it to be attached to or embedded within the monitored equipment.

Every Wireless Sound Level Meter Data Logger NSRTW mk2 purchased is provided with an Individual Manufacturer’s Certificate of Calibration from Convergence Instruments. This all-digital design includes the A, C, and Z weighting curves. It is enclosed in a completely weatherproof casing which is designed for indoors and outdoors applications. Its highly sensitive Type 1 MEMS microphone has a noise floor of 30 dB(A)and is ultra stable with time and temperature variations. The software includes an oscilloscope and spectrum analyzer features, as well as email alarms.

New Features of the NSRTW_mk2

  • Complies with the precision requirements of ANSI S1.4 and IEC651 standards – Type I
  • Type I precision (bandwidth selectable between 16 kHz and 20 kHz)
  • “Z” weighting (in addition to A and C) 
  • Open TCP/IP protocol to facilitate custom user applications/instrument interface
  • Server access via a domain name
  • Direct email alarms (no need to transit through the server)
  • Fast USB and WiFi downloads
  • Real-time recording while connected to PC (Use of the SLM as a high-quality digital microphone at 32 kHz and 48 kHz sampling rates)
  • New “universal” Manager application that can manage any instrument in the Noise Sentry RT series
  • As of 1st of June 2018 “Our NSRT_mk2 and NSRTW_mk2 now feature an expanded polytetrafluoroethylene (ePTFE) barrier that effectively protects the microphone against the ingestion of dust and water”.

Wireless Sound Level Meter Data Logger NSRTW_mk2 Applications

  • Sound level and acoustic dose measurement and recording.
  • Monitoring of safe working conditions.
  • Activity detection and logging.
  • Long-term measurement and recording of acoustic levels for environmental impact studies.
  • Specially designed for long-term outdoor applications.


BANDWIDTH 20 Hz to 20 kHz
PRECISION CLASS Complies with the precision requirements of ANSI S1.4 and IEC651 standards – Type I
SATURATION LEVEL (TYPICAL @ 1 KHZ) 120 dB-A, 120 dB-C, 120 dB-Z
TEMPERATURE ERROR Better than 0.6 dB (-20°C < T < 60°C)
SENSITIVITY TO VIBRATIONS 60 dBSPL/g (20 dB lower than typical measurement microphone)
NOISE-FLOOR (TYPICAL) 30 dB-A, 46 dB-C, 52 dB-Z
DUTY RATE OF SIGNAL CAPTURE 100% – No Missed Samples
MIN LOG INTERVAL 125 ms (8 points of Lmin, Lmax, and LEQ per second)
REAL-TIME SPECTRAL DISPLAY 2048-Point Power Spectrum – dB or Lin Scale.
CALIBRATION Field-calibrated using a 1/2″ calibrator
INTERNAL BATTERY TYPE Integral Li-Poly – USB-Rechargeable
RECHARGE TIME 2 h 30 (Typical)
INTERNAL BATTERY AUTONOMY (FULL-CHARGE) 7 days while recording (WiFi operation will drain battery slightly more, depending on the rate of connecting)
INTERNAL BATTERY LIFE > 300 Charge/Discharge Cycles
TEMPERATURE RANGE -20°C to 60°C (-4°F to 140°F)
RECORDING MEMORY Non-Volatile Flash Memory
RECORDING MEMORY CAPACITY (RT128 MODEL) 128 Mb, Ex: can continuously record Lmax, Lmin and Leq levels at 1s intervals for 32 days, or 10s intervals for 320 days.
DATA RETENTION Greater than 20 Years
DIMENSIONS 7.62 x 3.94 x 5.9 cm – (3” x 1.55” x 0.81”)
WEIGHT 100 g (0.1 lbs)
CONSTRUCTION Integrally Potted Weather-Proof ABS Enclosure
MICROPHONE DUST PROTECTION Expanded polytetrafluoroethylene (ePTFE) dust and water barrier