What is basic knowledge of audio? Just understand these questions

What is difference between civilian audio and professional audio? Civilian audio is intended solely for home audio playback; professional audio is designed for recording studios or live venues for monitoring or amplifying sound. Characteristics of civil audio: design is based on principle of aesthetic sound reproduction, paying attention to details such as sound field, sound of musical instruments in hall, and warm sound effect of concert hall. The style of product reflects personal passions of designer. Characteristics of professional sound: Based on principle of being true to essence of sound, we strive for texture and accuracy of sound. Professional products are easy to use and dynamic, have good reliability and performance, and are easy to install.

What is basic composition of a standard Hi-Fi system? According to this signal source (such as CD, DVD), signal connection line, preamplifier, power amplifier, speaker connection line, speaker.

What is Dolby Surround? Audio that encodes surround back channels into a stereo channel. Playback requires a decoder to separate surround signal from encoded audio.

What is Dolby pro-logic? Adds a front center channel to Dolby surround sound to block movie dialogue on screen.

What is Dolby Digital? Its digital audio, also known as AC-3, includes 5-channel signals: left front, center, right front, left surround and right surround, all of which are independent full range signals. There is also a separate channel for subwoofer effects. Commonly known as 0.1 channel, together it is called 5.1 channel.

What is THX and THX5.1? A surround sound standard developed by US-based Lucasfilm Corporation that enhances Dolby Pro Logic surround sound system and further enhances surround sound effect. The THX standard places stringent requirements on playback equipment such as audio and video sources, amplifiers, loudspeakers, rooms, and even wires. Only products that conform to this standard and have been verified by Lucas can bear THX logo. There are two different standards, "The Ultra" and "THX Select", of which THX Ultra is most stringent standard.

What is DTS? Abbreviation for split-channel digital home surround sound system. Also uses an independent 5.1 channel. Compared to Dolby Digital, it has a higher bit rate and higher resolution and is a strong competitor to Dolby Digital.

What is DSP technology? DSP is an acronym for Digital Signal Processing. When a dedicated microprocessor processes audio instruments in digital domain, it can simulate acoustics of venues such as concert halls, classrooms, jazz nightclubs, etc. DSP technology is also used to decode various surround waveforms.

What is a digital-to-analogue converter? A device that converts digital audio signals (i.e. DIGITAL) to analog audio signals (ANALOGUE) in digital audio devices (such as CDs, DVDs). The digital-to-analog converter can be turned into an independent machine and used with a CD player, often referred to nowadays as a decoder.

What are bits and bitstreams? The smallest unit of a binary digital signal that always assumes one of two states: 0 or 1. Bitstream is a Philips technology that converts CD digital signals to analog music signals.

What is subsampling and resampling? Sampling rate refers to rate at which a digital recorder or player samples a signal. For example, CD, DCC, and MD sample rates are set to 44.1 kHz, i.e. 44,100 samples per second, while DAT is set to 48 kHz, or 44.1 kHz. Digital audio broadcasting uses a sampling rate of 32K. The sampling rate determines highest frequency that a digital system can record. DVD-Audio uses a high sampling rate of 96 kHz. Oversampling means that sampling frequency is several times higher than standard 44.1 kHz sampling frequency of CD system. The purpose is to make it easier to filter out digital noise after D/A conversion and to improve phase distortion of CD player's recording frequency. CD players used 2x or 4x sample rate, recent machines have reached 8x or higher.

What forms of self-expression exist in world? Audio sources can be divided into two categories: analog and digital. The analog category includes AM/FM receivers, turntables, VCRs, etc., while digital category includes CD players, DVD players, SACDs, digital broadcasts, etc.

What is difference between Class A, Class B and Party A amplifiers? According to conduction mode of power amplifier tube in power amplifier, there are differences between class A, batch B, and class A and B. Class A, also known as class A, is a type of amplifier in which any element of amplifier's output power will have cutoff at current during entire signal cycle. Class A amplifiers generate a lot of heat during operation. Efficiency is very low, but inherent advantages are absence of crosstalk, and single-ended amplifiers frombelong to class A operation methods. Class B, also known as class B, is a type of amplifier in which two positive and negative half-cycles of a sine wave signal are respectively amplified and output by two sets of amplifying elements of a push-pull output stage in turn. operating time of each set of amplifying elements is half signal cycle. The advantage of class B amplifiers is high efficiency, but disadvantage is that they will give crossover distortion. Class A and B, also known as class AB, lies between class A and class B. The conduction time of each group of push-pull amplification elements is greater than half a signal cycle and less than one cycle. Class A and B amplifiers effectively solve crosstalk problem of class B amplifiers, and their efficiency is higher than that of class A amplifiers, so they are widely used.

What is difference between a tube amplifier and a transistor amplifier? Electronic tube amplifiers are commonly known as "tube amplifiers" or "tube amplifiers" and tubes are used as amplifying components; transistor amplifiers are commonly known as "stone machines" and transistors are used as amplifying components. At same output power, tube amplifier has strong overload protection, and distortion is small under condition of a strong signal: because tube amplifier is isolated by output transformer, low-frequency response is not as good as that of transistor amplifier. Lamp life is not as good as that of a transistor. Transistor amps can have more power and run faster than tube amps.