Nowadays, audio has become an indispensable device in our lives, because we can't imagine how to listen to computers and TVs when they leave the speakers. With the rapid development of technology, the current home speakers have become more intelligent. From the recent Google Google release, it can be seen that the future desktop speakers will be fully compatible with the home wireless network, and through mobile phones, tablets, notebooks. Computers and PCs control the sound of the speakers, which will undoubtedly make our lives more comfortable and relaxed.
Nowadays, the home audio on the market can be said to be a brand. The price ranges from tens of thousands of multimedia speakers to tens of millions of home theater speakers, and the style and style are more abundant; this is undoubtedly for consumers. A good thing, we can choose a wider range, but also promote the healthy competition of products, so that the quality of products is more secure. But even then, many consumers will still be scammed by pits. Unscrupulous merchants are the main reason, and consumers’ own understanding of some basic audio concepts also gives these unscrupulous merchants a chance. .
In fact, for consumers, the best way to prevent the fraudsters from being deceived is to understand the products themselves. Although we do not ask everyone to achieve professional standards, some basic audio concepts still need to be understood; Those unscrupulous businesses are easy to flicker, and this is especially important for small white users. Today, we will also make a summary and analysis of some audio concepts that are often confusing, from simple to relatively complex one by one, let Xiaobai users know more about the product; then let’s take a look at what is usually us. Ignore the audio concept that is easy to confuse.
Confusion concept 1: speaker and sound
Speakers and speakers:
Don't underestimate that this is a very simple concept. For many white users, they don't understand the difference and connection between these two words, and it is easy to confuse the concepts of these two words. First of all, the sound, it is a complete set of equipment (or a system), and the speaker is an integral part of the set of equipment, it can also be said to be the speaker in the sound, its role is to enlarge the power amplifier The signal becomes a sound signal and is transmitted to the human ear; in addition, the sound includes an external power amplifier, a sound source device, a decoder, an equalizer, a microphone, a transmission line, etc., and these independent devices are combined to form an audio system. . The home theater we usually talk about is a sound system.
The speaker is part of the sound system
The speaker is a sound output device
Let's talk about the speaker below. Simply put, it is a sound output device, which can also be called a speaker (but different from the speaker single form); it consists of a box, a speaker unit, a frequency divider and a power supply; Some speakers have a power amplifier inside, called an active speaker; those without a power amplifier are called passive speakers. Usually used at home with PCs are basically active speakers, and speakers used in home theaters or other audio systems basically do not have amplifiers, you need to connect external amplifiers.
Section: Sound is a complete system that contains speakers; the speakers are a single sound output device.
Confusion concept two: pre- and post-level
Pre and post:
If there are some friends who like “burning†equipment around us, you may often see that there are one or two devices on the desktop that are similar to external amplifiers; it is probably the pre- and post-level. So what exactly do they use? What is the difference between the two? We will explain it briefly here.
McIntosh C48 preamp (can be used to adjust the sound effect)
The so-called pre-level refers to the device with the effects of volume, bass/treble, balance, tone, echo, etc. Its function is to process the reception. The audio signal is, but the output signal of the previous stage is very weak. If we directly connect to the speaker, we will only hear a small sound. At this time, we need to send the sound signal to the subsequent stage for amplification, then we will You can hear a louder sound.
Hegel H4SE post amplifier (to enhance signal output power)
Hegel H4SE post amplifier internal circuit
The function of the latter stage (also called the post-stage amplifier) ​​is mainly used to enhance the power of the signal, that is, by increasing the current output in the box, the horn vibrates in the magnetic field generated by the current; in short, the front stage is transmitted to Its signal strength increases and then passes to the horn, and the human ear can hear a loud sound. The common active speakers on the market integrate the front and rear stages on one circuit board at the same time; while the front and rear stages of high-end audio equipment are divided into two devices, the sound quality performance will naturally be much better.
Bar: The front stage is responsible for the adjustment of the volume and sound effects; the latter stage is responsible for increasing the power of the signal output.
Confusion concept three: op amps and amplifiers
Op amps and amplifiers:
The full name of the op amp is called an operational amplifier. It is literally used for signal calculation and amplification, and can also add and subtract signals. Its operational characteristics have been widely used in computer computing components in the early days, and then widely used. In various fields. In the field of multimedia speakers, the op amp chip is mainly responsible for the calculation functions of volume, tone and peripheral effect adjustment. For example, the integrated operational amplifier is used in the front stage of the audio and the headphone amplifier (amp).
NE5532 op amp chip
Different types of op amps have different effects on sound. For example, the sounds we feel when listening to music are warm, full, dry, round and so on, all obtained through the op amp; currently the types of op amps on the market are very Many, low-end op amp chips like JRC4558 are the most commonly used in ordinary power amplifiers and multimedia speakers. Although the sound performance is average, the cost is low, and it is more suitable for use with low-end power amplifiers and speakers. In addition, high-end op amps such as the NE5532, LM833, and LF353 are mainly used in high-end audio equipment, and the sound will naturally be much better.
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