Izdelava in meritev značilnosti elektrostatičnega zvočnika

KASTELIC, SERGEJ (author), Humar, Iztok (mentor)

V diplomski nalogi je predstavljena izdelava prototipnega elektrostatičnega zvočnika, ki bo služil kot vzorec in model za izboljšavo še dveh dodatnih elektrostatičnih zvočnikov, ki bodo namenjeni ozvočenju predavalnice na Fakulteti za elektrotehniko Univerze v Ljubljani ter študentom omogočili lažji prikaz delovanja elektrostatične sile. Opisano je tudi, kako deluje elektrostatičen zvočnik, in navedene so njegove glavne značilnosti, po katerih se razlikuje od klasičnih dinamičnih zvočnikov, ki so najpogosteje uporabljeni in najbolj poznani med ljudmi. Po izdelavi prototipnega elektrostatičnega zvočnika smo tudi izmerili in izračunali njegove specifikacije, kot so: frekvenčna karakteristika, maksimalna jakost zvočnika, kapacitivnost zvočnika, sile, ki delujejo v zvočniku, itd. Meritve in izračuni so pokazali, da ima prototipni zvočnik solidno končno zvočno jakost in dober raven frekvenčni odziv znotraj svojega razpona frekvenc. Tudi izračuni in meritve so dokazali dobro ujemanje med sabo. Treba je tudi upoštevati, da za poganjanje izdelanega zvočnika ni uporabljen ojačevalec najboljše kvalitete. Za še boljši zvok je treba imeti boljše ojačevalnike. Meritve so tudi pokazale, da je prototipni zvočnik zelo usmerjen. Da bi se izognili usmerjenemu zvočniku, bi bilo treba ukriviti statorje, ki bi bolj razpršeno oddali zvok. Prototipni zvočnik je izdelan po principu hibridnega sistema, ki združuje elektrostatičen zvočnik in dodaten zunanji nizkotonec, ki skrbi za nižje tone, kjer elektrostatičen zvočnik ne zmore. Celotni sistem je treba poganjati preko aktivne kretnice, ki skrbi, da zvočnika delujeta v določenem razponu frekvenc. Ugotovil sem, da sta za izdelavo potrebna strokovno znanje in strokovna pomoč. Čistim laikom ne priporočam izdelave, saj je treba imeti nekaj znanja o elektrotehniki in fiziki. Namen izdelave je prikaz, kako s strokovnim znanjem, pridobljenim na fakulteti, in nizkimi stroški izdelave narediti zvočnik, ki se lahko primerja z drugimi dragimi elektrostatičnimi zvočniki, primernimi za poslušanje visoko kakovostne glasbe.

• Language: Slovenian
• Keywords: elektrostatičen zvočnik, elektrostatika, zvok
• Work type: Bachelor thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2016
• PID: 20.500.12556/RUL-85128
• Publication date in RUL: 13.09.2016

Secondary language

• Language: English
• Title: Electrostaic loudspeaker - production and measurement of characteristics

Abstract

The thesis presents the making of the electrostatic loudspeaker prototype which will serve as a sample and a model for improvement of two additional electrostatic loudspeakers destined for a lecture room wiring at the Faculty of Electrical Engineering, thus enabling an easier presentation of electrostatic force performance to the faculty students. Furthermore, the thesis also describes the performance of the electrostatic loudspeaker and its major characteristics which make it different from classic dynamic speakers that are most often used and known among people. After the electrostatic speaker prototype had been made, we measured and calculated its specifications, namely frequency characteristics, maximum sound level, speaker capacitance, working forces in the speaker. The measurements and calculations showed that the prototype has a solid final sound level and a good level of frequency response within its frequency span. In addition, the calculations and measurements showed good mutual consistency. It also has to be taken into consideration that the amplifier used was not of best quality. Therefore, better amplifiers should be used for better sound. The measurements also showed that an immersive speaker was much directed. To avoid directed speaker, stators should be curved for the sound to be more dispersed. The prototype was made on the principle of a hybrid system that merges an electrostatic speaker and an additional outer subwoofer that ensures bass sound where the electrostatic loudspeaker cannot. The whole system has to be driven through an active switch which ensures that the two speakers work in the specific frequency span. The conclusion is that the making of the prototype loudspeaker requires professional knowledge and professional help. Lay people are not advised to make such a speaker, for they lack enough knowledge of electrotechnology and physics. The purpose of the making of the prototype was to show how to, with the knowledge acquired at the faculty and at low cost, make a speaker comparable with other more expensive electrostatic loudspeakers appropriate for listening to high-quality music.

• Keywords: electrostatic loudspeaker, electrostatics, sound