PENGUAT KELAS D DENGAN METODE SUMMING INTEGRATOR

A class D amplifier is one in which the output transistors are operated as switches. When a transistor is off, the current through it is zero and when it is on, the voltage across it is small, ideally zero. Thus the power dissipation is very low, so it requires a smaller heat sink for the amplifier. Class D amplifier operation is based on analog principles and there is no digital encoding of the signal. Before the emergence of class D amplifiers, the standard classes were class A, class AB, class B, and class C. The classic method for generating signals driving a transistor MOSFET is to use a comparator. One input is driven by an incoming audio signal, and the other by a triangle wave or a sawtooth wave at the required switching frequency. The frequency of a triangular or sawtooth wave must be higher than the audio input. MOSFET transistors work in a complementary manner that operates as a switch. Triangle waves are usually generated by square waves fed to the integrator circuit. So the main part of processing audio signals into PWM (Pulse Width Modulation) is the integrator and comparator. In this paper, we will discuss the work of a class D amplifier system using the summing integrator method as its main part.

Microbeads preparation with reversed-phase microemulsion and ultraviolet light curing for digital encoding suspension array

Microbeads preparation with reversed-phase microemulsion and ultraviolet light curing for digital encoding suspension array.

Show me a strathspey: taking steps to digitize tune collections

Purpose The present paper describes an Arts and Humanities Research Council (AHRC) research project into Scottish fiddle music and the important considerations of music digitization, access and discovery in designing the website that will be one of the project’s enduring outcomes. Design/methodology/approach The paper is a general review of existing online indices to music repertoires and some of the general problems associated with selecting metadata and indexing such material and is a survey of the various recent and contemporary projects into the digital encoding of musical notation for online use. Findings The questions addressed during the design of the Bass Culture project database serve to highlight the importance of cooperation between musicologists, information specialists and computer scientists, and the benefits of having researchers with strengths in more than one of these disciplines. The Music Encoding Initiative proves an effective means of providing digital access to the Scottish fiddle tune repertoire. Originality/value The digital encoding of music notation is still comparatively cutting-edge; the Bass Culture project is thus a useful exemplar for interdisciplinary collaboration between musicologists, information specialists and computer scientists, and it addresses issues which are likely to be applicable to future projects of this nature.