{"id":17370,"date":"2023-03-28T08:48:35","date_gmt":"2023-03-28T06:48:35","guid":{"rendered":"https:\/\/mag.ebmpapst.com\/en\/?p=17370"},"modified":"2025-08-12T10:05:39","modified_gmt":"2025-08-12T08:05:39","slug":"soundcheck-for-heatpumps-psychoacoustics-for-minimum-noise-generation","status":"publish","type":"post","link":"https:\/\/mag.ebmpapst.com\/en\/industries\/heating\/soundcheck-for-heatpumps-psychoacoustics-for-minimum-noise-generation_17370\/","title":{"rendered":"Sound\u00adcheck for heat\u00adpumps: Psychoa\u00adcoustics for minimum noise gener\u00ada\u00adtion"},"content":{"rendered":"\n

In prin\u00adciple, a heat pump works like a refrig\u00ader\u00adator, which with\u00addraws heat from the food stored in it and trans\u00adfers it outside. Air\/water heat pumps extract heat from the surrounding air and transfer the heat to the heating system, which warms the living areas or is used to heat water. Fans ensure the neces\u00adsary external air flow through the device\u2019s evap\u00ado\u00adrator and inevitably generate more or less noise during oper\u00ada\u00adtion. This also applies to the fans with EC motors that are partic\u00adu\u00adlarly quiet. Where they are installed can also have a nega\u00adtive impact on noise gener\u00ada\u00adtion. Noise gener\u00ada\u00adtion always needs to be consid\u00adered by those who use air\/water heat pumps. As a rule, it is not usually suffi\u00adcient to merely observe the limit values of the local stan\u00addards and noise protec\u00adtion ordi\u00adnances.<\/p>\n\n\n\n

Psychoa\u00adcoustics: Why does a noise sound unpleasant?<\/h2>\n\n\n\n

The values defined in the guide\u00adlines and stan\u00addards, which can be measured on the test stand, have little to do with indi\u00advidual human noise percep\u00adtion. Until now, stan\u00addards and direc\u00adtives have not adequately dealt with tonality, i.e. the rela\u00adtions between tones. Different psychoa\u00adcoustic tests are currently looking into this. Psychoa\u00adcoustics aims to define why we perceive noise as pleasant or unpleasant. For example, trumpet music and an exca\u00advator at a construc\u00adtion site have approx\u00adi\u00admately the same measur\u00adable sound power, but our psychoa\u00adcoustic assess\u00adment of them is completely different.<\/p>\n\n\n\n

Fig. 1: Das Psychoakustik-Labor f\u00fcr Testh\u00f6rer:innen bei ebm-papst in Mulfingen. (Photo | ebm-papst)<\/figcaption><\/figure>\n\n\n\n

Motor and fan specialist ebm-papst studied this issue early on and set up a special psychoa\u00adcoustics labo\u00adra\u00adtory for test subjects to demon\u00adstrate the oper\u00adating noise of heat pumps and the fans installed in it in various config\u00adu\u00adra\u00adtions (Fig. 1).<\/p>\n\n\n\n

\n
<\/div>\n\n\n\n

The best prod\u00aducts for your heat pumps<\/h3>\n\n\n
\n
<\/figure>\n<\/div>\n\n\n

Heat pumps absorb energy from their surround\u00adings and then feed it into the heating or service water system.<\/p>\n\n\n\n

\n
Learn more <\/i><\/a><\/div>\n<\/div>\n<\/div><\/div>\n\n\n\n

Mini\u00admize oper\u00adating noise of air\/water heat pumps<\/h2>\n\n\n\n

Devel\u00adopers ques\u00adtion the subjects after\u00adwards to build up a scien\u00adtif\u00adi\u00adcally founded data\u00adbase, for example based on the following key psychoa\u00adcoustic para\u00adme\u00adters: loud\u00adness [sone], sharp\u00adness [acum], pitch [mel], rough\u00adness [asper] and fluc\u00adtu\u00ada\u00adtion strength [vacil]. In addi\u00adtion, tonality and stim\u00adulus are also signif\u00adi\u00adcant vari\u00adables. Tonality is present when single tones are notice\u00adable within a noise, which increases the inter\u00adfer\u00adence effect. Noises that contain rapid changes in level, e.g. knocking or ramming noise, are iden\u00adti\u00adfied with impul\u00adsive\u00adness. <\/p>\n\n\n\n

\n

The results from the psychoa\u00adcoustics labo\u00adra\u00adtory are incor\u00adpo\u00adrated into fan devel\u00adop\u00adment.<\/p>\n<\/blockquote>\n\n\n\n

Both impul\u00adsive\u00adness and tonality can be measured with micro\u00adphones and compared with the test subjects\u2019 state\u00adments. Assess\u00adments by the test subjects are analyzed using statis\u00adtical and psycho\u00adlog\u00adical methods. The results are incor\u00adpo\u00adrated into in-house fan devel\u00adop\u00adment, but also provide infor\u00adma\u00adtion about the tested air\/water heat pumps and which fans are best suited to the indi\u00advidual instal\u00adla\u00adtion scenario. Ulti\u00admately, the aim is to ensure that the oper\u00adating noise of a high-quality heat pump that is already very low is perceived as pleasant by the widest possible group of test subjects.<\/p>\n\n\n\n

Metric for psychoa\u00adcoustic eval\u00adu\u00ada\u00adtion<\/h2>\n\n\n\n

Research on psychoa\u00adcoustics is in full swing and we can look forward to more results. As part of a doctoral thesis carried out at ebm-papst, for example, it has already been possible to develop a metric, which is now used for psychoa\u00adcoustic eval\u00adu\u00ada\u00adtion in the end device.<\/p>\n\n\n\n

\n

ebm-papst acoustic quality model<\/h3>\n\n\n
\n