Once upon a time, we were immersed in various styles of music to sort out our thoughts, but we didn’t seem to care much about the sound quality of “that song”. As long as the music is good, all problems can be solved easily.
But today is not what it used to be, we are no longer the “caged bird” who only lives in our own world. The evenings come and go, the sun and the moon fly by, in the modern city woven by the bustling, everyone needs a quiet place of one acre, accompanied by beautiful melodies and impressive sound quality, let the thoughts get closer to the depths of memories again.
This issue of audio-visual strategy will take everyone to appreciate the economics of the HIFI circle! Let’s explore the “optimal strategy” for building an audio playback system!
Two camps of audio playback systems
Any complex system can be stripped away and classified into categories to simplify its structure, making it easier for us to see the “mystery” in it. The audio playback system is no exception. We can divide it into two main camps according to the actual needs of different HIFI enthusiasts: “headphone camp” and “speaker camp”.
It is a very popular way to use “headphones” as the final output device of the audio playback system. Headphones have won the favor of many new generation HIFI enthusiasts for their unique portability and excellent anti-interference performance. I have to sigh that times have changed and things are impermanent. If it was 10 years ago, I would definitely put the “speaker camp” first in the introduction. However, with the development of the mobile Internet and the rapid development of mobile phone hardware, earphones have become a very popular audio playback terminal device. Various audio hardware manufacturers have also launched a lot of matching HIFI fever hardware. Walking and listening to HIFI has become a trend!
Of course, headphones alone cannot be called a complete audio playback system. We also need some pre-audio processing equipment to form a complete audio playback system. At present, the simple solution for most people is to use a mobile phone to connect headphones to form a complete playback system. The reason why the playback system can be set up so conveniently is that the manufacturer of the mobile phone has integrated the complete audio processing circuit into the mobile phone, and the end user only needs to connect an additional pair of headphones to complete the set-up of the whole system.
HIFI enthusiasts who have worked with large-scale audio playback systems must know that building an audio playback system with speakers is a very complicated process. Many types of equipment are involved. We HIFI players need to choose the hardware equipment of each link of the audio playback system by ourselves, and consider their compatibility before connecting these equipment together. The sound of such a large-scale audio playback system is often unique, because the hardware equipment of each audio processing link is uniquely selected according to the audio knowledge and personal sound style preferences of HIFI enthusiasts.
Of course, not all playback systems built with speakers require a lot of energy and time to “study”. There will also be a one-stop solution on the market, suitable for “lazy people”. Just choosing these finished plans may not bring you extra fun, but I think these are not the key points. The most important point is that these finished plans are often expensive, and the premium is very high, which is somewhat “bullying the soft and fearing the hard”. It does not meet the “purpose” of our HIFI economics!
What the camps of the audio playback system have in common
Whether you choose the “headphone camp” or the “speaker camp”, the basics of their audio technology are the same. That is, systems from different camps have the same set of hardware. Let’s take a look at what links a complete audio playback system has and the corresponding hardware devices.
As the name suggests, the sound source is the source of the sound. It is usually a recorded sound. It can be stored in different media, such as early vinyl discs, magnetic stripe cassettes, or later CDs, DVDs, and now the most popular MP3 files and audio files in various encoding formats. The biggest feature of MP3 files and files in other digital audio formats is that they can be stored on any of our modern storage devices, such as computer hard drives, mobile phone flash memory, or professional hardware music players.
In particular, it should be mentioned that the early vinyl discs and magnetic stripe cassettes were all analog sound sources. Starting from CDs and DVDs, almost all audio sources on the market are digital audio sources, including various audio files in formats such as MP3.
The decoder is a product of the era of digital audio sources. If the requirement is to play an early analog audio source, then a decoder is not required in the entire playback system. The name of the decoder is a bit “sloppy”, why do you say that? Because, in today’s era when digital information technology is so advanced, the name “decoder” has some other meanings. It is easy to be confused by HIFI enthusiasts. But since the older generation of HIFI enthusiasts in China call it this way, we also need to be familiar with its “sloppy” name. The standard name of the decoder we introduce here should be called “Digital-to-Analog Converter”, the English abbreviation is DAC, and the Chinese full name is “Digital Signal and Analog Signal Converter”.
The role of the decoder is to convert the digital signal into an analog signal and provide it to the speaker (headphone or speaker). Since all speakers today are driven by analog signals, a decoder is an indispensable part of a digital audio source. Some experienced HIFI enthusiasts may refute this point of view, because they know that some special playback systems do not have a dedicated DAC chip. We will not discuss this special case here. Because its popularity is too low, there is almost no market, and few people use it. But no matter from which point of view, the link of converting digital signal to analog signal must exist, but whether this link is handled by a special decoding chip or handed over to other circuits, in some special playback systems, there may be problems. difference.
The full name of the power amplifier is “power amplifier”. After the digital-to-analog conversion of the sound source by the decoder, the generated analog signal is usually very weak and not strong enough to drive the speaker. Therefore, a power amplifier is needed to amplify these weak analog signals to a level that can drive the speaker to emit a suitable volume.
For power amplifiers, there is a relatively misleading information. That is, many people think that using earphones as the terminal output device does not require a power amplifier. They think that earphones have very little demand for electric power, so no power amplifier is needed. In fact, the analog signal output by the DAC is so weak that it is barely audible from any speaker, including small earbuds. And in portable devices such as mobile phones and hardware music players we use, power amplifier circuits have been integrated, so we don’t need to connect an independent power amplifier externally.
Our understanding of power amplifiers should not just stop at “big” independent power amplifiers. In this way, we can have more control over the various components of the system when building a HIFI audio playback system.
The loudspeaker is the end of the complete audio playback system. The analog signal output by the power amplifier circuit will be transmitted to the speaker, and the speaker will complete the final sprint. We end up hearing the sound reproduced in front of us in the speakers.
So, what exactly are speakers doing to an analog signal? In professional speaker manufacturers, the process done by the speaker is called “electro-acoustic conversion”. Through this name, we can simply understand what the speaker does to the analog signal. As far as the current technology is concerned, the analog signals output by the power amplifier are all “electrical signals”, and the carriers of these signals are all “electricity”. The specific meaning of “electro-acoustic conversion” is to convert electrical signals into sound signals. The sound signal is a signal that can finally be received by the human ear.
The fundamental view of HIFI economics
To put it bluntly, HIFI economics is how to “save money”! How to get the highest sound quality experience for the same money. This is why it is necessary to introduce the major components of the audio playback system before talking about the viewpoints of HIFI economics. The components of these playback systems need to be selected by us, and each component has an impact on the sound quality of the final sound. But the degree to which they affect the sound quality is not the same.
We should invest more money in the link and components that have the greatest impact on sound quality. Because upgrading this component can improve the whole system the most, we can get the biggest benefit by upgrading it.
Maturity of audio technology
As we look for the areas that have the greatest impact on sound quality, we need to understand the maturity of audio technology around the world today. I have mentioned more than once that audio technology is different from display technology. Compared with display technology, audio technology is much more mature and originated earlier. But if we must select the weakest link in the audio technology industry in all links of the audio playback system, it must be the link of “electro-acoustic conversion”.
The weakest link is the processing link that can improve the sound quality the most. Smart you must have noticed that “electro-acoustic conversion” is the processing link undertaken by the speaker. Therefore, when we set up any audio playback system, the first equipment that should be heavily invested should be the speakers. Switching to better speaker equipment will yield the highest benefit in sound quality improvement.
HIFI economics and HIFI system balance
When we explore HIFI economics, we should also realize that any system is “balanced”, and audio playback systems are no exception. The status of speakers in the whole playback system is of course very high, but we can’t think that as long as the speakers are good enough, other links can be ignored. When economic conditions permit, we should also pay attention to the “matching” between the various components when we build an audio playback system. Don’t take the viewpoint of economics as the only standard of practice.