Analyzing Low Frequency noise A(LF) and Infrasound Noise G(Infra)

The following document provides guidance for analysis procedure and accuracy considerations for two types of low frequency noise as described in the Danish Low frequency Requirements.

Low Frequency Analysis using noiseLABDownload

noiseLAB Batch 4.1.3

The new test version has minimal changes compared to the official shipping version 4.1, to maintain maximum compatibility.

Read Me File:

Applies to noiseLAB Batch 4.1.3 Exp Nov 15 2024.  This Version is no longer available.

Fixed Tone Analysis Error related 10 dB tone criteria for 10% of the critical bandwidth.  

Fixed minor tone graph error. Now the layering of the graphs will always be in the following order: Red Tones graph, Noise Pause graph, and Noise graph ensure properly graph overlap. 

New more user-friendly TDMS Viewer.

Development environment updated to LabVIEW 2024 Q3 for better performance and stability while maintaining backward OS Compatibility.

The Sound Quality function “Time Varying Loudness” suffered extremely poor performance.  This has now been rectified but the function cannot be used in Time Slice mode.

You should not uninstall version 4.1. However, we do not recommend having both versions open at the same time.

An official shipping version will be released after the test period. After November 15, version 4.1.3 will no longer function, and will not run with existing licenses.

Download link:

https://drive.google.com/file/d/1Knb9dLtLBVlqRCyUgb6yJr1MSl3-W4hj/view?usp=sharing

Click the download icon at the top of the screen.

If you get warnings, click continue.

Unzip the file.

Drill down in the folder to noiseLAB Batch 413setup to install noiseLAB Batch.

Install at the default locations prompted by the installer.

The readme file can be found in the “Data” file of the extracted download.

noiseLAB on Windows 11

Successful testing in progress on Windows 11.

• Equipment certification and traceability: We recommend that you install noiseLAB on a new PC running Windows 11 and keep your noiseLAB installation untouched on the older PC.

• Download and Installation

The executable files are now hosted on Dropbox. Dropbox may ask you to log in and also say “this fie is not supported”. Instead go to the File menu of Dropbox and select “Download”.

Windows 11 may refuse the save the file as an executable, but still downloads it and may give it another name. In this case, click on the triple dots to permit it to restore its .exe name.

Double click on the self-extracting .exe file. This requires administrator rights. The installation will then proceed. Only install at the suggested locations (i.e. the x86 folder which is where 32-bit programs are installed).

Open noiseLAB Capture, and copy the user info and license number into the relevant fields. As an extra security pre-caution, noiseLAB Capture will also require this the second time you load the program. noiseLAB Batch Processor will automatically pick up the license key installed by noiseLAB Capture.

• Operation

Windows 11 display scaling of 150% now works correctly with noiseLAB without mangling the front panel appearance. This will great aid readability when working on higher resolution screens.

Also note the installation notes for Windows 7 and 10 which also apply to Windows 11. These also fix a minor font issue in noiseLAB Capture

Use with modern versions of Word and Excel: This has not yet been fully tested.

• Hardware

Support of NI 9233. This works with DAQ-MX 2024 even though NI says it is not supported beyond 2018. This restriction may be due to limited support of multi-slot chasses.

• Performance

Modern PCs have more than adequate performance to handle noiseLAB. Increased memory to 16 or 32 Mbytes will give better performance for certain types of analysis as well as more responsive display updates of very long recordings.

If you perform very long analyses many types of analyses selected, a four-core or more machine may give better performance. noiseLAB automatically exploits additional cores. But if you only perform one type of analysis at a time, multi-core processors will not benefit you. On the Advanced tab you can benchmark the analysis time relative to real-time. For example, a factor of 60 means that the processing is 60 times faster than the effective channel recording time.

If you require a quiet PC, more moderately-specified computers, such as the Lenovo T14 will normally operate without significant fan noise.

noiseLAB is not supported on Mac.

Holiday Sale: Save10%. Leasing plan announced

noiseLAB Professional is now available with 10% holiday savings for orders received between December 1 and December 28, 2022.

The list price of noiseLAB Professional is €3950. For exact local price contact noiseLAB (or a distributor) on this page.

Now you can also lease noiseLAB at ⅓ of the list price one year at a time. After leasing for four years, you obtain a permanent license. The lease is binding for one year, If you stop the lease and then resume later, you still obtain credit for the years leased toward the four years required for an outright purchase. The 10% holiday sale discount also applies to the leasing.

Read more about noiseLAB Professional and download a demo here.

Tone Analysis in noiseLAB Batch Processor 4.1

In the Danish comparative noise measurement in 2021, a bug was identified relating the 10% tone criteria. In the screen shot below the 51 Hz band should not have been identified as a tone.

The tone analysis was based on an FFT Spectrum with a line spacing of 3 Hz from 20 Hz to 10 kHz with linear RMS integration of 90 seconds and a linear (Z) frequency weighting.

Tone analysis in noiseLAB Batch Processor 4.1:

The current shipping version, noiseLAB Batch 4.1 can be used to check whether it shows the correct tone values with respect to the 10 dB criteria of the Critical Bandwidth (CB). In the above screen shot, you can see the broad red range centered at 51 Hz (red identifying it as an audible tone) has at 12.2% width of the critical bandwidth, exceeding the 10% of the CB (see the lower right hand corner). Hence it should not have been identified as an audible tone.

The bug is relatively rare, and is primarily seen with broad, relatively flat “peaks” at lower frequencies. 

The correct tone analysis is shown in an early version of noiseLAB 4.2B1 below:

For participants in “Store Støjdag” in Denmark 2021, the calibration value used was 94.0 dB, vs. 93.8 dB in the above analyses.

A new test version rectifying this issue was released October 6, 2024.The upgrade is available free of charge for all existing users of noiseLAB Pro.

For more information see this link.

The above is available in Danish here Tone analyse og noiseLAB.

Research shows how to reduce noise annoyance without reducing the noise!

A EU sponsored research project FAMOS has shown how “moderators” reduce the annoyance. A moderator can be a factor such as the appearance of the noise source, for example by planting vegetation in front of noise barriers. The report gives multiple “moderators” giving inspiration to improving the overall noise environment. You can read the Guidebook of how to reduce annoyance. It is filled with important ideas and inspiration. You may think it sounds too good to be true, but the project has been carried out by serious, widely respected researchers and their associated organizations.

Internoise 2022 Paper.

Tone analyse og noiseLAB

The following is available in English here.

Der blev i forbindelse med afviklingen af den 26 sammenlignende måling i 2021 opdaget et fejl i noiseLAB, idet 10% tonekriteriet for en analyse af et 90 sekunder langt lydklip burde betyde en frasortering af tonen i det kritiske bånd (CB) med centerfrekvensen 51 Hz .

Den tilhørende toneanalyse som anvist ved opgaven er baseret på et FFT Spektrum med 3 Hz linjeafstand midlet over 90 sekunder og med 20 Hz nedre grænse for tone analyse (lineær frekvens vægtning Z)

Tone analyse i noiseLAB Batch 4.1:

Den eksisterende udgave af noiseLAB Batch 4.1 kan benyttes til at kontrollere hvad 3 dB båndredden som % CB (af den kritiske båndbredde) er. I ovennævnte figur, nederst til højre vises at toner i 51 Hz båndet har en båndbredde på 12.2%. Herved kan man konstatere at disse ikke skal regnes med i målingen.

Fejlen opstår primært ved lavere frekvenser, og karakterises visuelt ved meget brede tone områder.

Her er den korrekte tone analyse på samme data beregnet med noiseLAB 4.2B1:

Det skal bemærkes at disse analyser er udført med en kalibrerings faktor på 93,8 dB i stedet for 94 dB som i vejledningen.

En ny test version der retter fejlen er frigivet d. 6 oktober 2024.

Holiday sale: 10% off

To celebrate the holidays, we are providing a 10% discount on noiseLAB Professional in all of December 2021 and January 2022. This gives the convenience of placing the purchase order in the desired financial year.

When you buy factory-direct in the EU, the price is €3950 minus 10% which is €3555.

Upgrading from noiseLAB 3 Professional: The upgrade price is €995.

Purchasing links for noiseLAB

The latest date we can receive your purchase order and invoice in 2021, is December 27 when you order direct.

You can download the fully-functional demo at:

Download demo

Be sure to download both noiseLAB Capture 4.0 and noiseLAB Batch 4.1. You can activate using the demo key on the same page which also has a link to the full User Guide.

For a personal on-line interactive demo or for detailed questions: contact Carsten Thomsen at ct@pxi.dk

The fine print: We have a free 30-day return policy from date the license key is sent to you: No questions asked. Those customers who have purchased noiseLAB Professional in 2021, will receive a 10% discount on their next purchase.

noiseLAB: Help plan the future and visit our stand at “Store Støjdag”

noiseLAB will be exhibited at the above noise conference on October 4, 2021, and will be held in Danish.

At the conference we invite your input of what new features are most important for you.

The follow are some requests we have received and we can show prototypes of some of these.:

Add-on modules:

• Reverberation Inspector: For interactive evaluation of reverberation curves.
• Arbitrary signal generation with sequencing and repetition.
• Whole body vibration
• Multi-channel Frequency response, Impulse response (with editing).

Product enhancements:

Recording: Time Scheduled, Triggered Recording. Very long recordings (unlimited) in 1 hour segments. User-defined markers during recording.

.wav files: Improved .wav file import and export

Picture/Video support

Input Channels: Up to 16 channels. Mix of acoustic and other parameters, such as temperature and various general AC/DC signals from products such as the NI 9215.

Editing: Automatic clip creation. Pre-naming of Recording before or during recording. Enhanced automatic clip naming. “Exclude” editing.

Analysis: FFT: very high resolution down to 0.001 Hz. Zoom FFT. AM Demodulation. Sound Quality metrics: Bug Fixes and better performance. Reverb. Multi-channel Human Vibration including classification. 3D waterfall plots. Intensity plots. Multiple plots on one graph. Multiple cursors. Frequency Response function, and associated cross spectra, impulse response and editing hereof.

Improved export of tables and graphs. Searching and sorting of result lists. Simple post-processing of results.

Project: Input channel configuration saving. Merging of multiple projects.

Pricing: Outright purchase or subscription model?

Your input is valued: Whether you attend the conference or not, your input is always important. You can send it to ct@pxi.dk

noiseLAB Transferred to CTXI

As of June, 2021, all rights to noiseLAB have been transferred to CTXI ApS.

CTXI is owned by Carsten Thomsen, who has led the development of noiseLAB for more than 10 years.

All current customers will serviced by CTXI under the existing licenses and associated conditions.

noiseLAB can be purchased as usual at the following link.

I look forward to continue to work with you! It is my goal to continue to provide you with first rate support.

Best Regards,

Carsten Thomsen