Merjenje moči zvoka : diplomsko delo

Ocepek, Primož (author), Bulić, Patricio (mentor)

Pri izdelovanju in testiranju novih izdelkov je postalo priporočljivo, da se izmeri koliko zvoka oddaja izdelek. Trend narekuje, da morajo biti naprave močnejše, boljše, vendar morajo oddajati manj zvoka kakor ostali izdelki. Zaradi trendov o tihih napravah je postalo znanje o akustiki in merjenju zvočnega nivoja moči priporočljivo, pri nekaterih gospodinjskih izdelkih pa celo obvezno. Diplomsko delo na kratko predstavimo vsa predznanja, ki so potrebna za razumevanje zvočnega nivoja moči. Predstavitev predznanja se prične s predstavitvijo zvoka. Predstavimo kaj je zvok, ter iz katerih zvokov lahko izračunamo nivo zvočnega nivoja moči. Prav tako predstavimo zvočno polje, po katerem zvok potuje. Da so postopki meritve enaki so nastali standardi, ki določajo korake meritve zvočnega nivoja moči. Po predstavitvi zvočnih polj in standardov predstavimo merilno verigo, ki predstavi kako zvočni signal pride v računalnik. Po teoretični predstavitvi sledi predstavitev, kako se ključni elementi, ki so prisotni pri merjenju zvočnega nivoja moči izračunajo. Predstavimo konstantni delež oktavnega spektra, utežitvene fukncije ter šume in tehnike odpravljanja šumov, ki so prisotni pri meritvah. V drugem delu diplomske naloge predstavimo aplikacijo s katero bomo izvajali meritev zvočnega nivoja moči,ter predstavimo meritveni pogled. Prav tako predstavimo izdelek v okviru diplomskega dela. Po predstavitvi aplikacije razložimo postavitve mikrofonov in opišemo koliko mikrofonov je potrebnih za opravljanje meritve zvočnega nivoja moči. V tretjem delu diplomske naloge predstavimo realno meritev zvočnega nivoja moči. Za merjeno napravo je bil izbran prenosni računalnik. Naprava je bila merjena v različnih okoljih in v dveh stanjih. Meritve so bile opravljene v podjetju Dewesoft in podjetju Gorenje. Rezultate iz podjetij pa smo primerjali s rezultati, ki so bili na spletni strani. Po opravljenih meritvah smo prišlji do zaključka, da so rezultati na spletnih straneh napačni, ter ugotovili zakaj je prišlo do napačnih rezultatov. Pri delu v prihodnje pa se bomo osredotočili na razvoj in nadgradnjo obstoječe aplikacije in tako zmanjšali možnosti odstopanja med rezultati.

• Language: Slovenian
• Keywords: zvok, zvočna moč, zvočni nivo moči, zvočni tlak
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FRI - Faculty of Computer and Information Science
• Publisher: [P. Ocepek]
• Year: 2015
• Number of pages: 56 str.
• PID: 20.500.12556/RUL-72436
• COBISS.SI-ID: 1536608195
• Publication date in RUL: 17.09.2015

Secondary language

• Language: English
• Title: Sound power measurement

Abstract

In process of making and testing new products it has become quite important how much noise product is producing. Trends dictates that new products must be more powerful better but producing less sound than other products. The trends made knowledge about acoustics and sound power level recommended. In making of household appliances is knowledge even mandatory. Thesis introduces all knowledges necessary for understanding sound power level. First we introduce what is sound and from which sounds we can calculate sound power level. We also introduce sound fields. We also introduce standards which are necessary because standards describes steps in measuring sound power level. After introducing sound fields and standard we describe audio signal path. After theoretical part we introduce key factors which are include in measuring sound power level. We introduce constant percentage bandwidth, weighting filters and noise which are included in measurement. In second part of thesis we introduce application with which we will measure sound power level. We introduce usage and describe measurement view. We also describe work we have done for thesis. After describing application we describe microphone position and how much microphones is needed for measuring sound power level. In third par of thesis we describe real measurement of sound power level. For measured device was selected laptop. Measurement was measured in two environments and in two situations. First environment was in company Dewesoft. After first measurement in company Dewesoft we measured in company Gorenje. Results of measurements were compared with result published on web page. After measurements we have came to conclusion that results published on internet were wrong. We also recognized the mistakes the measurement had. In the future we will focus on developing and upgrading sound power level application so the tolerance between others applications are smaller.

• Keywords: sound, sound power, sound power level, sound pressure