Coronavirus Update - NOVA Acoustics Ltd remains open for business during this uncertain time following the COVID-19 outbreak.  All Government advice and recommendations are being followed by our staff and site engineers.  


Cesva SC420 Class 1 Sound Level Meter

Sound level meter and spectrum analyser

Integrating Sound level meter class 1 with audio recording expandable to spectrum analyzer for third octave bands

INCLUDED Audio recording with pre-recording and voice comments.

Increased storage with MicroSD memory card

Automated Parameters: timers, DEN thresholds, external input: 

         1) Auto start/stop of measurement and logging

         2) Auto audio recording & pre-recording

Erasing backward (BACK ERASE function)

Built-in USB & BLUETOOTH® connectivity

Sensitivity, date & time change history

Ready for environmental monitoring: 

         1) Auto ON and automatic measurement and logging start

         2) Downloads while measures

Free or diffuse sound-field correction options

Can be expanded with advanced measurement modes (see optional Modules)


Main Features


The ON&PLAY philosophy has been developed to be intuitive - getting first time users up & running quickly & providing a stress-free return to measurements, even after long periods of inactivity.

ON&PLAY offers a simple and enjoyable experience from the first moment of contact with the device.

With ON&PLAY, measurement has never been so easy.

Removable MicroSD memory card

The information measured by the SC420 (final results and time histories), audio files and voice notes are saved on the MicroSD card inserted into the SC420.

Once the measurements are complete and the SC420 is powered-off, the MicroSD card can be removed and inserted into a computer. The data can then be transferred using the program 'Memory Download' - the download can be completed much faster this way.

4 GB class 4 microSD cards have been tested successfully

Modular Platform

The SC420 is an instrument that stands out for its power, versatility & ergonomics. It delivers high performance as a Class 1 integrating sound level meter (in accordance with IEC 61672, ANSI S1.4 and ANSI S1.43).

Thanks to its modular platform, the SC420 can be expanded with advanced measurement options such as 1/3-octave band spectrum analysis, FFT analysis and reverberation time measurement.

Automated Parameters

The SC420 has a complete system of automated parameters, such as starting & stopping measurement and audio recording. Automatic timers and triggers are also available when exceeding threshold by DEN time-zones .

Its power and versatility offer infinite combinations which will provide optimal performance for even the most demanding of users.  

Ready for environmental monitoring

The SC420 is designed to work as an automatic continuous noise monitoring unit. An environmental monitoring powering option is available, which allows measurements to be resumed after recovery from a power failure.

Optimal file structuring allows efficient data transfer & manipulation; this includes downloading while measuring and erasing parts that have already been downloaded.

Audio recording and voice comments

USB and Bluetooth® connections

Back erase

The SC420 can record audio files (listening quality), whilst it logs acoustic functions, facilitating its subjective evaluation and the recognition of sound sources.

The SC420 communicates with a PC through a USB port and through Class 1 wireless Bluetooth® communication, in order to download & manipulate data, as well as allowing external control and real time visualization.

With the Back erase function, the SC420 can delete the last 10 seconds of the measurement in progress. This option is ideal when unwanted noise events occur during measurement.




What does it measure?

Occupational noise mode simultaneously measures all the parameters necessary to evaluate the noise exposure of the worker with and without hearing protectors (SNR, HML and Octaves).


  • Industrial acoustic
  • Noise measurements for air conditioning installations (HVAC)
  • Sound Insulation measurements
  • Frequency analysis of industrial noise, environmental and labour
  • Background noise in rooms

From £382.00



What does it measure?

16 Hz to 16 kHz octave band filters analysis plus overall functions and NC and NR curves


  • Sound insulation measurements
  • Noise measurement for air conditioning installations ( HVAC)
  • Frequency analysis of industrial noise, environmental and labour
  • Background noise in rooms

From £374.00



What does it measure?

10 Hz to 20 kHz 1/3-octave band filters analysis plus overall functions


  • Sound Insulation measurements in  third octave band
  • Assessment of environmental noise (Corrections for the presence of tonal and impulsive components and low frequency content)
  • Detection and identification of noise sources

From £872.00



What does it measure?

Reverberation time measurement by 1/1 and 1/3-octave bands using the interrupted noise and the integrated impulse response methods. Includes parameters for the evaluation of non-linear decay curves and the influence of the filters


  • Evaluation of the reverberation time of rooms
  • Measurement of sound absorption in a reverberation room
  • Measurement of sound insulation in buildings and of construction materials

From £828.00



What does it measure?

FFT Analysis of 10000 lines from 0 to 20000 Hz (2 Hz/line)


  • Detection and evaluation of the tonal components
  • Frequency analysis of continuous and transient signals (industrial and environmental)
  • Evaluation of tonal components according to ISO 1996-2 and DIN 45681.

From £748.00



What does it measure?

Records WAV (uncompressed) format audio files, 24 bits resolution, 48 kHz sampling frequency and constant gain for later analysis


  • This mode can be advantageous independently of the application in which it is being used as it allows a perfect acquisition of the audio signal, to carry out a post processing and obtain additional information.

From £765.00


Table of standards

Type-approval Certificates

IEC 61672-1:2002

Class 1 Sound level meter

11/09/2013: Type examination
IEC 61260:1995

/A1:2001 Class 1 Filters


25/07/2013: Software
OIML R 58:1998

Class 1 Sound level meter

07/10/2013: Additional 1 Type examination
OIML R 88:1998

Class 1 Integrating sound level

27/09/2013: Additional 1 Software
OIML R 130:2001

Class 1 Filters

11/11/2013: Additional 2 Software
ANSI S1.4-1983(R2006)

/ANSI S1.4a-1985(R2006) Class 1 Sound level meter

30/05/2014: Additional 3 Software
ANSI S1.43-1997(R2007)

Class 1 Integrating sound level

07/11/2014: Additional 4 Software
ANSI S1.11-2004(R2009)

Class 1 Filters

22/05/2015: Additional 5 Software
EN 61260:1995

/A1:2001 Class 1 Filters

18/12/2015: Additional 6 Software
EN 61672-1:2003

Class 1 Sound level meter


Complies with 73/23/CEE and CEM 89/336/CEE low-tension regulations, the latter amended by 93/68/CEE.

17/02/2014: Type-approval Certificate




The SC420 sound level meter measures a lot of functions for very long periods of time and also records audio files automatically. The best way to approach the analysis of all these functions together with the qualitative information provided by the audio files is to use the CESVA Lab software application.

Download and configure

CESVA Lab is cost free and gives you a simple way  to download all the information from the SC420 by simply removing the microSD card and post-process it. It also allows you configuring the SC420 from the PC.

View and Listen

Moreover, it provides an intuitive and user-friendly interface which allows numerically and graphically display of all the measurement information on the screen in several synchronized panels (spectrum and time history graphs and 3D spectrograms) and listen to the audio files for each sound event.  

Export and Report

To navigate through the information, CESVA Lab has an audio and mark browser and a very powerful zoom  and pan tool for finding the desired section and then automatically generate a PDF report.  

Edit and re-calculate

If what you want is to recalculate a section, simply select it, add it to a layer and simply calculate. Different layers, containing  several sections,  can be calculated simultaneously. Each layer is calculated and saved in a separate file.  

Complete Sets

Cesva EM542

Sound Level Meter Set consisting of: SC420 sound level meter, CB006 Sound level calibrator, TR40 tripod, and ML043 transporting briefcase


Cesva EM242

Sound Level Meter Set consisting of: SC420 sound level meter, CB006 Sound level calibrator, and ML013 transporting briefcase


Cesva EM642

Sound Level Meter Set consisting of: SC420 sound level meter, CB006 Sound level calibrator, TR40 tripod, and ML063 transporting briefcase


Optional Accessories

Cesva CB006 Class 1 Acoustic Calibrator

Class 1 Acoustic Calibrator


Cesva TR040

Tripod for sound level meter, dosimeter and microphone. Maximum height 1.1 meters


Cesva TR050

Tripod for sound level meter, dosimeter and microphone. Maximum height 1.55 meters


Cesva AM300

Mains Transformer 220V to 5V


Cesva ML043

Carrying Case (48 x 37 x 16 cm) for SC420, acoustic calibrator and Tripod


Cesva ML063

Carrying Case Special Weather (51 x 38 x 15 cm) for SC420, acoustic calibrator and Tripod


Cesva TK200

Outdoor Kit for outdoor measurements with desiccator, microphone and preamplifier protections against rain, wind and birds. Includes 3m cable, ML011 carrying case and AK250 adapter for microphones C240 and C140, Microphone C-130 does not need adapter. Kit for Class 1 sound level meters (SC420, SC310 and SC101)


Cesva CN003

Extension Cable for Preamplifier and Microphone (3 m)


Cesva CN010

Extension Cable for Preamplifier and Microphone (10 m)


Cesva CN030

Extension Cable for Preamplifier and Microphone (30 m)


Cesva CN420

Multi-connector Cable (RS232 serial port, AC output, Digital output, Digital input)


Cesva TR001

Tripod support for the preamplifier and microphone


Cesva PR003

 Extension Rod for microphones (3 m). Adaptor for microphone supplied


Cesva AM150

Battery Converter 12V to 5V