7 research outputs found
Loudspeaker as a treatment for room acoustics
This paper deals with possibilities of using the loudspeaker for room acoustic. The experiment with large low resonant frequency loudspeaker was done. At first, the vibration of membrane was scanned by using a laser vibrometer for different operating states. The effect on reverbereation time of placing the loudspeaker in echoic chamber was also investigated
Construction of amplifier for guitar
Tato bakalářská práce je zaměřena na návrh a konstrukci elektronkového zesilovače určeného pro elektrofonickou kytaru. Zesilovač má dva kanály, efektovou smyčku, koncový zesilovač s výkonem pro použití v domácích nebo studiových podmínkách a polovodičový usměrňovač. První část práce obsahuje teoretický úvod do problematiky nástrojových zesilovačů a popis používaných řešení u komerčně vyráběných zesilovačů. Další částí je návrh jednotlivých bloků zesilovače. V závěru jsou shrnuty výsledky po testování zesilovače.Katedra aplikované elektroniky a telekomunikacíObhájenoThis bachelor thesis deals with the design and construction of vacuum tube amplifier
for electrophonic guitar. The amplifier has two channels, the effects loop, power amplifier
with performance for using at home or in studio and semiconductor rectifier. The first
section contains theoretical introduction to the instrumental amplifiers issue and solution
description commonly used in commercially produced amplifiers. Another section is
focused on amplifier blocks design. Testing amplifier results are discussed in the end
Acoustic treatments of small listening rooms.
Tato diplomová práce je zaměřena na akustické úpravy malých poslechových prostorů. V úvodu práce jsou probrány základní teoretické znalosti z prostorové akustiky a měření parametrů prostorů. Jedna kapitola je věnována přehledu používaných akustických prvků. Další část práce se zabývá řešením akustických parametrů vybrané místnosti. Na základě měření bylo navrženo několik akustických prvků. Pohltivé panely byly zkonstruovány a jejich parametry byly ověřeny v dozvukové komoře. Výsledky měření jsou shrnuty v závěru práce.ObhájenoThis master thesis deals with acoustic treatments of small listening rooms. The introduction
discusses the basic theoretical knowledges of room acoustics and measurement of
room parameters. The fourth chapter is involved to an overview of the acoustic elements. Another part deals with the solution of acoustic parameters of the chosen room. It has been proposed several acoustic elements on the basis of measurements. The absorbing panels were constructed and their parameters were verified in a reverberation chamber. The measurement results are summarized in the conclusion
Měření akustických rezonančních pohltivých prvků
Tento článek vznikl za podpory interního projektu na podporu studentských vědeckých konferencí SVK-2018-005 a projektu SGS-2015-020: Vícekanálové měřicí metody.This paper deals with possibilities of measuring resonance frequency of
absorbing elements using the loudspeaker. Commonly used methods for determine
absorbtion coefficient α are not suitable for prototypes design. For verification in
the reverberation chamber a large sample area is required. In impedance tube can
be measured only small circular samples. The method, which is described in the
paper, is based on change of the loudspeaker impedance characteristics due to
placing prototype of the absorbing element into a common baffle
Possibilities of verifying the parameters of the absorbing elements using the loudspeaker
This paper deals with other option of determination of the acoustic absorbing materials parameters. Simplified procedures are often used to design new absorbing elements. These procedures are based on an ideal model or previous experience. The result is often quite inaccurate. To verify the absorption coefficient α, measurements in the reverberation chamber or impedance tube are required. Both of these methods require expensive and special equipment, which is not available to everyone. For measurement in the reverberation chamber it is necessary to have approx. 10 m2 of the measured sample. In the impedance tube there are measured only small circular samples and the coefficient α only for the perpendicular impact of sound waves. Thus, these methods are not suitable for designing prototypes of new absorbing elements. For this reason, other possibilities for determination of important parameters on a relatively small prototype sample were investigated. The result of this research is an experiment describing a possible measurement method. This method is based on change of the loudspeaker impedance due to placing prototype of the absorbing element into a common baffle
Measurement of parameters of the eCall system transmission channel for passenger car
Emergency call system, which in the case of traffic accidents ensure rapid assistance to motorists, will be mandatory for all new passenger cars approved since 2017 - 2018. The speech intelligibility as one of the parameters of eCall developed for cars depends on parameters of the transmission channel. Due to the internal design and arrangement of the car interior, there are not many suitable variations of speaker location in terms of quality of speech transmission. Therefore, ITU standards provide the recommended values and measurement procedure of important parameters. The paper deals with methods of measurement RLR, THD and SNR parameters inside the car
Design and Characterization of Embroidered Electroacoustic Transducer
This paper is focused on designing and characterization of embroidered electroacoustic transducer placed on the magnet. This type of transducer can be used as a feedback or notification element in an advanced smart textile system. Multiple transducer designs and threads were used in the experiment. Results from measuring of acoustic level have showed, that embroidered electroacoustic transducer can be used as a full-featured speaker for the feedback system. The results have showed the ability to play simple sounds and melodies through this electroacoustic transducer.This paper is focused on designing and characterization of embroidered electroacoustic transducer placed on the magnet. This type of transducer can be used as a feedback or notification element in an advanced smart textile system. Multiple transducer designs and threads were used in the experiment. Results from measuring of acoustic level have showed, that embroidered electroacoustic transducer can be used as a full-featured speaker for the feedback system. The results have showed the ability to play simple sounds and melodies through this electroacoustic transducer