NSRT_mk4

321.00 $

SKU NSRT-mk4 Category Tag
New microphone with
extended dynamic range

Sound level meter datalogger with a dust-protected class 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.

FCC CE

TECHNICAL EQUIPMENT - FREE EXPERT GUIDANCE

This sound level meter comes in 4 configurations depending on:

  • Monitoring duration required (weeks vs months)
  • Connectivity (USB, WiFi, Cloud)
  • Integration with your systems

→ An expert can guide you to choose the perfect solutions for your need (it's free)

The Sound Level Meter Data Logger NSRT_mk4 is the 4th generation of Convergence Instrument’s smart integrating sound-level meter/datalogger. It includes a type 1 digital MEMS microphone, an accurate date/time clock, and a non-volatile 128 Mb recording memory with a fast USB download.

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

Every Sound Level Meter Data Logger NSRT mk4 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.

Mounting Base and Tripod Adapter are included.

Sound Level Meter Data Logger NSRT_mk4 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 outdoors applications.

✔️ Get help from noise expert for choosing the right model

✔️ Optimal configuration and specs for your project

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In stock (can be backordered)

Key Features

Class 1 Precision

Class 1 sound level meter with digital MEMS microphone for accurate measurements

USB Connectivity

Fast download and monitoring capabilities for flexible deployment

Extended Battery Life

Up to 5 days of battery life with integrated rechargeable battery

Outdoor Ready

Dust-Protected weatherproof enclosure for long-term outdoor installations

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Product Tabs

Product Description

The Sound Level Meter Data Logger NSRT_mk4 is the 4th generation of Convergence Instrument’s smart integrating sound-level meter/datalogger. It includes a type 1 digital MEMS microphone, an accurate date/time clock, and a non-volatile 128 Mb recording memory with a fast USB download.

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

Every Sound Level Meter Data Logger NSRT mk4 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.

Mounting Base and Tripod Adapter are included.

Sound Level Meter Data Logger NSRT_mk4 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 outdoors applications.

Features

  • NEW FEATURE: Measurement and recording of Lpeak
  • Class I precision
  • A, C and Z weighting curves.
  • Integrating Sound-Level Meter, records Lpeak, L-max, L-min and Leq levels.
  • Log interval adjustable from 125 ms (8 points per second) up to hours.
  • Individual Manufacturer’s Certificate of Calibration from Convergence Instrument provided with every instrument purchased.
  • Digital very sensitive MEMS microphone (29 dBA typical noise floor)
  • Completely sealed weatherproof enclosure designed for outdoors applications. Now includes an ePTFE membrane that seals the microphone against dust and water.
  • All-digital design.
  • Ultra-stable sensitivity (field recalibration is easily done, but seldom required)
  • Very low sensitivity variation due to temperature changes
  • Very low sensitivity to vibrations
  • Software function calculates CNEL, Lden, Percentiles and many other metrics.
  • Adjustable response time.
  • Preprogrammed recording start date/time.
  • Integrated oscilloscope function that can show the acoustic signal in real time.
  • Integrated spectral analyzer function that can show the spectrum (or 3rd-octave bands) in real time.
  • Can be used as a high-quality USB digital microphone
  • Allows the observation of recorded levels while the recording is ongoing.
  • Works standalone, or USB connected.
  • Long life internal rechargeable battery that recharges from USB and most USB chargers.
  • Can be field-calibrated.
  • Observes and records 100% of the acoustic signal (no missed samples).
  • Editable individual custom ID for easier instrument management.
  • All settings are stored in non-volatile memory. So the instrument will regain full functionality from hard-reset or battery loss.

Specifications

Bandwidth

20 Hz to 20 kHz

Microphone Sensor

Digital MEMs

Precision Class

Complies with the precision requirements of IEC61672-2002 Class I

Saturation Level (typical @ 1 kHz)

120 dB-A, 120 dB-C, 120 dB-Z
133 dB-A, 133 dB-C, 133 dB-Z (instruments shipped after December 15 2025)

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)

Weighting Curve

dB-A, dB-C, dB-Z

Noise-Floor (Typical)

30 dB-A, 46 dB-C, 52 dB-Z
29 dB-A, 32 dB-C, 36 dB-Z (instruments shipped after December 15 2025)

Recording Resolution

0.1 dB

Duty Rate of Signal Capture

100% – No Missed Samples

Min Log Interval

125 ms (8 points of Lpeak, 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

Connectivity

USB

Internal Battery Type

Integral Li-Poly – USB-Rechargeable

Recharge Time

2 h 30 (Typical)

Internal Battery Autonomy (Full-Charge)

7 days while recording

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.

Recording/Erasure Cycles

Greater than 100 000

Data Retention

Greater than 20 Years

Dimensions

19 mm x 42 mm x 160 mm – (0.75” x 1.65” x 6.25”)

Weight

100 g (0.1 lbs)

Construction

Weather-proof enclosure

Microphone Dust Protection

Expanded polytetrafluoroethylene (ePTFE) dust and water barrier

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CALL US: 819-575-1990

Mon-Fri 9am-5pm EST

Which Model to Choose?

Feature NSRT_mk4 NSRTW_mk4 NSRTW_mk4 Cloud
Price Base price (no WiFi) Higher (adds WiFi) Highest (WiFi + Cloud service)
Battery Life 5 to 7 days on battery, months while externally powered Similar autonomy on battery, WiFi reduces battery time. Similar autonomy on battery, WiFi reduces battery time
WiFi Built-in No Yes Yes
24/7 Cloud No Optional / via local setup Yes, 1Y included
Best For Short-term logging with local download WiFi projects with local IT / VPN Remote 24/7 cloud noise monitoring
Clients Use the NSRTW_mk4 For

Clients Use the NSRTW_mk4 For:

🏗️

CONSTRUCTION SITE MONITORING

(3-6 months)

"We monitor sound levels for municipal compliance"

→ Industries: Contractors, Municipalities

🏭

INDUSTRIAL COMPLIANCE (OSHA/HSE)

"Continuous measurement for workplace safety standards"

→ Industries: Manufacturing, Factories

🌳

ENVIRONMENTAL IMPACT STUDIES

(6-12 months)

"Data collection for environmental reports"

→ Industries: Consulting firms, Government

5.0
Based on 7 reviews
5 star
100
100%
4 star
0%
3 star
0%
2 star
0%
1 star
0%
1-5 of 7 reviews
  1. DP
    DP
  2. A
    A

    Great, thank you

  3. BJ
    BJ

    Great product, amazing customer service

  4. A
    A

    Great. Thanks Bruno..

  5. RH
    RH

    Good, easy and fast.

    Thanks

Software Description Importance Download
Instrument Manager Universal Installer Instrument Management Software Essential Install BEFORE connecting the instrument
Noise Sentry RT Community Noise Metrics Installer An application to calculate various noise metrics, such as CNEL, LDEN… and many others Optional
Instrument Disk Recorder An application to stream to disk the acoustic signal Optional
NSRT AutoCalc An application to calculate and automatically export standard metrics to Excel (LEQ, Lmin, Lmax, percentiles…etc.) Optional
NSRT Directivity An application to show the frequency response and directivity pattern Optional
NSRT_mk4 NSRT_mk4_Dev NSRTW_mk4 (Wireless) NSRTW_mk4 MQTT (Wireless)
Precision Class Type I Type I Type I Type I
Connectivity USB-only USB-only USB & WiFi USB & WiFi
Email Alarm Functions No No Yes No
Cloud Solution Compatibility No No Yes No (designed to work with a standard MQTT broker)
Weighting Curves A, C, Z A, C, Z A, C, Z A, C, Z
Values measured Lpeak, Lmin, Lmax, LEQ L instantaneous, LEQ Lpeak, Lmin, Lmax, LEQ Lpeak, Lmin, Lmax, LEQ
Recording of Acoustic Signal Included Optional (USB-Audio option) Included Included
Attachment System Wall or Tripod Mountable Wall or Tripod Mountable Wall or Tripod Mountable Wall or Tripod Mountable
Weight 3.3 oz
93 g
50 g 3.3 oz
93 g
3.3 oz
93 g
Data Non-Volatile N/A Non-Volatile Non-Volatile
Settings Non-Volatile Non-Volatile Non-Volatile Non-Volatile
Software Instrument-Manager
NSRT-Community-Noise-Metrics
Instrument-Manager Instrument-Manager
Instrument-Listener
NSRT-Community-Noise-Metrics
Instrument-Manager
NSRT-Community-Noise-Metrics
Timer Yes No Yes Yes
FFT Resolution (For Real-Time Display Only, Not Recording) 2048 points 2048 points 2048 points 2048 points
Generic Audio Driver Support Included Optional Included Included
Generic Com Port Driver No Yes No No
Platform Support Windows Windows, MacOS, Linux (and any platform that includes a generic USB CDC-class driver) Windows Windows
Open Communication Protocol No Yes (VCP over USB) No Yes (MQTT over WiFi)
Rechargeable Battery Autonomy 7-Days (Recording) No Battery 7-Days (Recording) 7-Days (Recording)
Recording Memory 128 Mb No Memory 128 Mb 128 Mb