Sainsbury SuperMarket Checkout

“Supermarket checkout” by Velela at English Wikipedia

It is rare these days that you can be somewhere without noise pollution intruding on some level. Many natural noises may be welcome; a dawn chorus or waves breaking on the beach, but when it comes to man-made decibels it’s a different matter.

Never mind the sounds of cars, ring tones and other noises that we take for granted, have you ever noticed how utterly surrounded we are by the humble “beep”? From reversing vehicles to supermarket checkouts, they punctuate our daily lives.

Continue reading »

Cirrus Research plc is a Key Sponsor of the Institute of Acoustics

Cirrus Research is proud to be a Key Sponsor of the Institute of Acoustics, the UK’s professional body for those working in acoustics, noise and vibration.

The Institute of Acoustics was formed in 1974 from the amalgamation of the Acoustics Group of the Institute of Physics and the British Acoustical Society (a daughter society of the Institution of Mechanical Engineers).

As Key Sponsors, Cirrus supports the Institute in a number of ways, with our staff regularly participating in a wide range of meetings, conferences and events. Many of our staff are members of the Institute at various grades and several of our current team are undertaking the IOA Diploma in Acoustics and Noise Control.

40 Years of the Institute of AcousticsCirrus has been involved with the Institute of Acoustics, or IOA, for many years and with 2014 marking the 40th year of the Institute, we’re delighted to be supporting the IOA at its anniversary conference at the NEC in Birmingham from the 15th to the 16th October 2014. More details of this event are available on the IOA website here.

The status of Key Sponsor is held by Cirrus and one other company and is the highest level available as a sponsor, a position of which we are very proud.

About the Institute of Acoustics.

The Institute has some 3000 members from a rich diversity of backgrounds, with engineers, scientists, educators, lawyers, occupational hygienists, architects and environmental health officers among their number. This multidisciplinary culture provides a productive environment for cross-fertilisation of ideas and initiatives.

The range of interests of members within the world of acoustics is equally wide, embracing such aspects as aerodynamics, architectural acoustics, building acoustics, electroacoustics, engineering dynamics, noise and vibration, hearing, speech, underwater acoustics, together with a variety of environmental aspects.

The lively nature of the Institute is demonstrated by the breadth of its learned society programmes.

More information about the Institute of Acoustics can be found on the website at

Cirrus-Hull-Council-Trojan-Noise-Nuisance-Recorder-Case-StudyNeighbourhood Enforcement Officer Nick Tindall has worked for Hull City Council for over 20 years in a variety of roles so he is no stranger to change when it comes to dealing with neighbourhood disputes, anti social behaviour and noise nuisance.

The local population in Hull has changed quite dramatically over recent years with immigrants settling in established neighbourhoods, children’s activities and expectations changing when it comes to ideas of entertainment, and housing needs also evolving with many of the larger pre-war homes now split into multi occupancy units to meet the demand for single living and migrant workers.

“We work closely with Council Housing officers when it comes to noise nuisance within Council housing stock but Environmental Health look after the private sector,” explained Nick. “Our job has changed over recent years; people seem less tolerant of each other, more belligerent perhaps. They don’t seem so willing to put up with something that perhaps a few years ago they would have sorted out over the garden fence.

“Our department get around 3,500 complaints a year with Environmental Health about the same number.  With each one we have to assess the severity and perhaps ask the complainant to fill in diary sheets of when the nuisance takes place.  We then may send a letter or speak to their neighbours and get a quick resolution but other times we need to gather more evidence that a statutory nuisance is actually taking place – that’s where Trojan comes into its own.”

Trojan and its most recent upgrade Trojan ² are noise nuisance recorders that have been designed with the specific needs of Noise Nuisance Officers in mind.

On average, Nick will leave the Trojan in situ for up to 5 days. The Trojan is mains powered with secure cables but it will switch to its own internal batteries if the mains power is lost. When power is restored, the Trojan will automatically restart even if its internal batteries are spent. This allows continuity and Nick knows that they are recording everything over a set period of time.

“I really like the pre-record function, it is very handy,” said Nick. “We have captured evidence using this function that has proven cases but, just as importantly, disproved them so innocent people aren’t been accused of causing a nuisance and having their tenancy’s threatened.”

The Pre & Post Trigger options for audio recording can be set as needed. The pre-trigger can be up to 30 seconds and post-trigger up to 60 seconds – particularly useful for catching out falsified recordings.

“We installed one Trojan with a gentleman who had complained about his neighbour but thanks to the pre and post record options we actually caught him also being very abusive to his neighbour. In the end they both had their private tenancy agreements removed.

“Fortunately Council tenants do tend to be law abiding on the whole; they don’t want to risk losing their tenancies or having it changed from “Secure” to “Introductory” where they have fewer rights. The main problems come from the private rental sector.”

As well as the Trojan technology that allows Nick to get the best evidence possible, he also stressed it was important that they can be in and out of people’s homes as quickly as possible. “The rucksack it comes in is great for this,” he added. “It is discreet and we can be in and out without arousing suspicion. It’s so easy and fast to set up we don’t waste time – it does the job of an officer where we can’t due to time constraints and not knowing how or when the noise is going to occur.”

Of the thousands of cases that cross Nick’s desk, the Trojan also helps him and his team to disprove some allegations, ensuring neighbour disputes aren’t being blown out of proportion or fabricated.

“We had one lady who complained that her neighbour was shouting very personal obscenities at her through the walls. We installed the Trojan but when we reviewed the recordings there was nothing there. We could hear the lady moving around and doing jobs so we knew the Trojan was working and in the end we got her help through her G.P. as it was different kind of support she needed.”

The most common complaint that Nick and his team deal with is loud music, followed by loud TVs and computer gaming. “It’s a sign of the times,” he explained. “Sounds systems and TVs are getting more sophisticated and cheaper all the time and a lot of them have speakers at the back or sides and are wall mounted. Teenagers on computer games also just don’t realise how loud they are playing when they are caught up in the moment or perhaps playing at times when other people are trying to sleep.”

The new Trojan² offers a high quality, high resolution audio recording as standard using a 16bit/16kHz uncompressed WAV file. This gives plenty of frequency range (up to 8kHz) and a wide dynamic range (up to 96dB) so audio recordings can handle both high and low levels with no loss of quality.

“Having a Trojan is like having another officer on the team,” concludes Nick. “It’s got good displays and downloading the data is very easy. It does everything we want at the end of the day.”


  • High resolution colour OLED screen with backlit keypad
  • Repeating measurements for environmental noise monitoring120dB dynamic range in a single span
  • 4GB memory with 32GB option
  • Simultaneous measurement of all parameters
  • 16bit/16kHz or 32bit/96kHz audio recording
  • Option of real-time 1:1 & 1:3 octave band filters from 6.3Hz
  • AuditStore™, Acoustic Fingerprint™ & NoiseTools as standard without any installation or licensing restrictions. It also has free updates.
  • Compatible with the CK:670 Outdoor Measurement Kit


Any questions?Contact us for more information about the Trojan Noise Nuisance Recorder

If you’ve got an old DAT Recorder based Noise Nuisance Kit, now’s the ideal time to trade it in and upgrade to the Trojan2 Noise Nuisance Recorder.

Here are a few of the benefits of upgrading from a DAT based system to the Trojan2 Noise Nuisance Recorder:

  1. Noise levels and audio recordings are automatically synchronised together into one simple package
  2. Play back the audio recordings from within the NoiseTools software and view the noise levels at the same time
  3. No more listening to hours of tapes to find the important recordings or storing boxes of old recordings
  4. Simple to use and setup – The Trojan is supplied as a complete system with no options or accessories needed
  5. Very wide measurement range with high quality audio recording so there’s no risk of overload or under-range during measurements
  6. Install the software onto as many PC’s as needed with no dongles, keys or licencing restrictions
  7. Trade-in your old kit against a new Trojan system and get the very latest technology
  8. Use the sound level meter in the kit for handheld environmental noise monitoring

The original Trojan was designed using feedback from existing customers and users of noise nuisance recorders and we incorporated a range of features and functions that these users requested.

The new version of the Trojan, the Trojan2, adds even more functions and features including:

  • Quicker and simpler removal of the cables for transport and storage
  • Less cables to connect to the sound level meter
  • More space in the case for storing accessories
  • A simple way to add a wired hand switch if needed

We’ve also made a number of updates to the software inside the Trojan to allow measurements to be made over longer periods of time as well as making download of measurements quicker.

Upgrade to the Trojan2 Noise Nuisance Recorder

Upgrade to the Trojan2 Noise Nuisance Recorder

The Trojan has been designed from the ground up to give you all of the functions and features that you need from a Noise Nuisance Recorder and here’s just a few of the key features and functions:

  • Designed specifically for EHO’s & housing associations to monitor noise nuisance
  • Complete class 1 noise nuisance recording system
  • Simple setup & operation
  • Wireless remote controls provided
  • Measurement of all parameters
  • High quality, High resolution uncompressed audio recording
  • Licence-Free software with free lifetime updates, no dongles or installation limits
  • Automatic startup & restart
  • Pre and post trigger audio control with data logging down to 10m/sec
  • Automatic audio calibration allows recordings to be played back at the correct volume
  • Designed manufactured and supported in the UK
  • Detachable class 1 environmental noise measurement sound level meter

To find out more about the Trojan or to discuss a trade-in against your current equipment, call us on 0845 230 2434 or click the “Any Questions” button below and let us know how we can help.

The Trojan Noise Nuisance RecorderAny questions?

Download the introduction to the Trojan Noise Nuisance RecorderDesigned to meet the needs of Environmental Health Officers, Housing Associations and anyone who needs to measure, monitor and record noise nuisance, the Trojan Noise Nuisance Recorder is both simple to use and easy to deploy.

After consultation with existing customers and users of noise nuisance recorders, we’ve included a range of standard features to help ensure you get the best from the equipment.

Features designed around our customers needs…

When we were designing the Trojan, we spoke to both existing and potential users to find out what was really important and which features they through were essential. The Trojan has been designed using these comments and feedback and on the following pages there are a few of the key points that we’ve incorporated following this research.

vTrojan Noise Nuisance Recorder

Quick, simple and easy to set up

When you are deploying a noise nuisance recorder, it’s vital to know that you’ll get good quality recordings and noise measurement data. With the Trojan, there’s no need for step-by-step instructions as it’s just a matter of plug in, calibrate and you’re ready to go.  If you forget to press start, the instrument will automatically start measuring after 10 minutes.

Wireless remote control
It may seem a simple thing, but having a wireless remote control was the most common request that came out of our research. If your user has limited mobility or if the noise nuisance recorder is placed in a different room, being able to start and stop the kit without having to run back to the box can be very useful.

It can often be the difference between getting a useful, good quality recording and no recording at all. The Trojan is supplied with 2 remote controls, either of which can be used with the kit, and we can supply additional units if you need to replace or add more and we can supply a wired hand switch if needed. Continue reading »

doseBadge Noise Dosimeter in useCirrus Research was pleased to sponsor Southampton Solent University’s first conference on Noise in Music and Entertainment which was held on March 5th.

This one day conference hosted by Solent Acoustics™, the professional acoustics consultancy arm of Southampton Solent University was designed to benefit anybody who may be affected by, or needes to improve their understanding of noise from entertainment, whether planning an event, managing premises, providing technical services or dealing with compliance and regulation.

The one day event featured four presentations from industry experts and an industry-specific trade show. The presentations were given by Andy Shiach of Advanced Communication Solutions, Jim Griffiths of Vanguardia consulting, Chris Turner of Adnitt Acoustics and Michael White of Test Valley Borough Council.

Commenting on the sponsorship, James Tingay, Group Marketing Manager at Cirrus Research said:

“Cirrus Research sees the Noise in Music and Entertainment Conference as a great opportunity to network with key figures in the music and entertainment business. We are very much looking forward to meeting visitors to the event who are as passionate and committed as we are to ensure that levels of noise at music and entertainment events don’t adversely affect those involved in the industry or people who wish to enjoy it.

James continued: “Cirrus Research offers a range of products that help to protect musicians, sound engineers, event organisers and a wide range of people involved in the music and entertainment world.  Our product range includes the Optimus noise level meters and doseBadge Noise Dosemeter.”

See related products for octave band analysis


optimus product selector

optimus product selector

Our optimus sound level meters cover a wide range of applications and have a varied selection of features which means that there’s an optimus sound level meter that is ideal for every application.

But the question is often asked “Which one should I choose?”.

To help you find the best instrument for your application or needs, we’ve created a simple product selector that allows you to choose the features that you need, such as Leq, 1:1 Octave Bands or Audio Recording.

The selector will then remove the instruments that don’t meet your criteria and you can choose from the recommendations.

Once you’ve chosen the instrument that you are interested in, you can see some detailed information about the product and then either call us or use the online form to request more details.

Why not try the optimus selector at and find the ideal optimus sound level meter for you.

We are delighted to announce that the optimus red and optimus green sound level meters have been Type Approved by the PTB in Germany!

The Class 1 CR:171 (optimus green) and Class 1 CR:161 (optimus red) sound level meters have been type approved by the PTB to the latest standards for sound level meters, DIN EN 61672, which is the same as IEC 61672.

The Physikalisch-Technische Bundesanstalt (PTB) is the German National Metrology Institute and is recognised as one of the most prestigious national test laboratories in the world.

After a series of long and detailed tests, which include both electrical and acoustic verification, approval numbers have been issued for the Class 1 optimus green and optimus red instruments as follows:

CR:161A, CR:161B & CR:161C
CR:1710, CR:171A & CR:171B

The approval numbers are:

21.21 / 12.02 for the CR:171 series (CR:1710, CR:171A & CR:171B)

21.21 / 12.03 for the CR:161 series (CR:161A, CR:161B & CR:161C)

The standards that were used in the verification were:

DIN EN 61672-1: 2003-10: „Elektroakustik – Schallpegelmesser – Teil 1: Anforderungen“
DIN EN 61672-2: 2004-08: „Elektroakustik – Schallpegelmesser – Teil 2: Baumusterprüfungen“
DIN 45657: 2005-03: „Schallpegelmesser – Zusatzanforderungen für besondere Messaufgaben“

What is Type Approval?

Type Approval, or Pattern Approval, is a method where a test laboratory such as the PTB tests an instrument against a set of standard tests to ensure that it meets the performance claims of the manufacturer.

The optimus sound level meters have been designed to meet the requirements of IEC 61672 (and the corresponding EN and DIN standards) and so these independent test have been carried out to verify that that the instruments do indeed meet these requirements. The IEC 61672 standard is in three parts.

The first of these is known as Electroacoustics – Sound level meters – Part 1: Specifications  and this defines the performance specifications for the instruments.

Part 2 is known as Electroacoustics – Sound level meters – Part 2: Pattern evaluation tests and this defines the tests and checks that a laboratory must carry out when they are testing an instrument for Type or Pattern approval. These are the tests that the PTB have been carrying out on the optimus sound level meters.

Part 3 is known as Electroacoustics – Sound level meters – Part 3: Periodic tests  and this defines the tests that should be carried out during a Periodic or routine verification.

This post has more information about the different sections of the IEC 61672 standard.




the Measure Issue 2The latest issue of our newsletter, the Measure, is available to download as a PDF. Just click on the image to open the document.

If you would like to receive a printed copy of this or future issues of the Measure, just let us know.

You can use the form on the right hand side of this page or you can sign up for our newsletter here.

Download the introduction to the Trojan Noise Nuisance RecorderNewham Borough, located just five miles east of the City of London, has experienced huge amounts of regeneration and redevelopment over the last twenty years through government investment schemes for Newham and the surrounding boroughs.

Muhammad Islam, Senior Environmental Health Officer at Newham Council’s Noise and Nuisance team, explains: “The diversity within Newham Borough makes it a vibrant and exciting place to live.

However, like all boroughs, we have our challenges such as noise nuisance complaints – of which we get on average, around 155 a week from residents.”

To help obtain vital information and record concise and clear data to support noise nuisance cases, Newham Council has recently invested in two Trojan Noise Nuisance Recorders from Cirrus Research.

The Trojan helps local authorities and housing associations provide quick and accurate noise measurements to support noise nuisance cases and it is supplied in a discreet backpack, allowing the officer who installs the Trojan to leave with the same backpack, so as not to arouse the suspicion of neighbours.

Read more about how the Cirrus Trojan is helping Newham Council monitor and manage noise nuisance in our new Case Study. Click here to download the PDF.


The Trojan Noise Nuisance RecorderLearn more about octave band intsruments

© 2014 NoiseNews