Quieter engines with NVH testing

Minimising noise, vibration and harshness (NVH) has become a top priority for engine makers. With different territories and their diverse NVH standards, our expert engineers study NVH characteristics in engines and machines and develop solutions that meet customers’ needs.

State-of-the-art sound technology allows us to offer services that exceed what many Original Equipment Manufacturers (OEMs) have in-house.

Our engineers work from initial concept to installation to deliver refined engines for a modern world.

As engines and machines have become more refined, engine makers are placing more emphasis on reducing NVH. Perkins uses state-of-the-art facilities to develop quiet engines and applications that meet varying NVH standards across the world.

NVH is now a consideration from the inception of the New Product Introduction (NPI) process all the way through to engine validation and installation. Our approach is to make applications ‘quiet by design’, so we invest time at the design stage, with our team of computer-aided engineering (CAE) designers, using world-class modelling and the best available software focusing on NVH sensitive features and parameters.


Our world-class facilities include three semi-anechoic chambers


Our specialists assist with machine integration and specific requirements (such as operating in an urban environment) and work closely with OEMs to fine-tune applications or meet certain NVH standards on certain machines.

Testing for NVH

Noise levels are measured in semi-anechoic chambers using high-speed data-logging and analysis equipment. Tools such as microphone array mapping, together with sound quality analysis can then be used to identify the best method of noise reduction.

For vibration, we have to ensure when developing new engines, that vibration levels are within acceptable limits to prevent component failure. Modal analysis methods are used to correlate virtual component models, CAE analysis is then further used to optimise designs.

Harshness is a subjective quantity; it’s about making engines and machines sound better. Engine sound is recorded and then analysed using various sound quality metrics to predict acceptability as design changes are introduced. Panels of assessors are used throughout the development journey to ensure acceptable engine sound is attained.

“NVH is now a consideration from the NPI (new product introduction) process all the way through to engine validation and installation.” Malcolm Trimm, global sound solutions

Quieter engines, quieter applications

While it is the application, not the engine, that must meet a territory’s NVH standards,Perkins recognises the need to work with OEMs to produce quiet engines, which in turn helps create quieter applications.

NVH can also affect a driver’s in-cab experience. An engine exhibiting good NVH characteristics implies quality and makes a good impression with customers and end users.

Among our team’s successes is the impressive evolution of the 1100 Series. Our engineers have increasingly minimised noise for greater operator comfort and to meet NVH standards in different territories. In our most advanced models, noise levels have been reduced by up to five decibels – this is equivalent to a reduction in noise levels of over 65%.

Design validation

Our NVH engineers use state-of-the art facilities and their capabilities include:

  • Three semi-anechoic chambers at the NVH research laboratory for engine and small machine assessment. This complements our quiet-by-design approach by validating optimised designs
  • High-speed camera and ‘modal analysis’ to understand and refine component vibration
  • Development of strategies to meet NVH objectives for engines and machines
  • Sound-quality development and verification for engines and machines. We address subjective sound issues by identifying ‘what makes an engine sound good?’
  • Machine in-cab and external sound refinement
  • State-of-the-art measurement and analysis technologies

Whatever level of refinement you need from an engine or application, you can trust our expert NVH engineers to work closely with you to meet your required noise standards.