What should you pay attention to when buying a sound card?

As the saying goes, you cannot be a true audiophile without a sound card. As everyone's requirements for sound quality are getting higher and higher, a sound card is an essential accessory. A sound card looks like a small box with many interfaces, but it is not that simple to buy. You need to consider many aspects, such as which formats are supported, the number of interfaces, connection methods, etc. If you are about to buy a sound card and don’t know how to choose, you will understand after reading this article.

If you are a newbie, let’s first take a look at what a sound card is and why you need one. If you already have a basic understanding of these, please skip to the second page.

What is a sound card?

There are two types of sound cards: built-in and external. The built-in sound card is an accessory in the computer host. There are motherboard integrated sound cards and independent sound cards. The sound card we are talking about today refers to an external sound card.

Be sure to pay attention to these three issues when purchasing a sound card

Built-in sound card

(Picture source: Baidu)

External sound card ( Hereinafter referred to as: sound card), it is hardware that can connect microphones, musical instruments and computers. It is shaped like a flat box, a bit like a router without an antenna.

Be sure to pay attention to these three issues when purchasing a sound card

External sound card

(Picture source: Baidu)

The sound card can The analog signals collected through microphones or musical instruments are converted into digital signals and transmitted to the computer through USB interface, FireWire interface or PCIE interface. In turn, the sound card can also convert the digital signal output from the computer into an analog signal and output it through the monitor speakers or headphones.

Why use a sound card?

Some people may ask, isn’t the sound card already integrated into the computer? Why do we need an external sound card? For ordinary users who do not have high requirements for sound quality or recording needs, a computer integrated sound card is enough. But for music lovers, do they have the nerve to call themselves audiophiles without a sound card?

From a technical point of view, the number of I/O interfaces on the computer's integrated sound card is limited. Generally, there is only one stereo line input, one headphone output, and one stereo line output, which is completely insufficient for recording. .

Be sure to pay attention to these three issues when purchasing a sound card

When recording a band, each instrument must be connected to the sound card (Picture source: Baidu)

For example, a band When recording, each instrument must be connected to a sound card, and if there are lyrics, vocals must also be recorded. At this time, a multi-channel sound card must be selected to meet the needs.

In addition, integrated sound cards will also have electromagnetic and radio interference problems. Excessive jitter and delay will have a great impact on the input and output of audio signals.

Page 2: Choose a suitable interface

I/O interface

As we just mentioned, there is a reason why it is recommended that audiophiles equip an external sound card. There are many interfaces, so when purchasing a sound card, you must first check whether the number of interfaces can meet your needs.

The more interfaces a sound card has, the higher the price will be. Therefore, it is not OK to just buy the one with the most interfaces, but to choose based on your actual needs. For example, if you mainly record songs by yourself, then a sound card with two or three input interfaces is enough; if you want to form a band, it depends on how many instruments you have, plus vocals, and you should choose a sound card with enough interfaces to connect it. Existing sound sources, and 1-2 spare sound cards are available.

Be sure to pay attention to these three issues when purchasing a sound card

Pay attention to the number of sound card interfaces

(Picture source: Baidu)

In addition to the number , the interface type also needs to be considered.

If you want to use a large-diaphragm condenser microphone, you need to ensure that the sound card has phantom power; if you need to connect a sound card to an instrument, you need to make sure that the sound card has an instrument-level high-impedance input. (Hi-Z input) interface. Line-level inputs and outputs are suitable for connecting external processing units, headphone amps and monitor speakers.

For ordinary beginners, the digital input and output interface is not very important, but it will be useful later when entering a deeper stage. For example, some high-quality microphone amplifiers will integrate S/PDIF output. If the sound card has an S/PDIF input interface, you can connect it to the microphone amplifier through it to avoid occupying the line level input interface.

Connection interfaces to computers

Audio is probably the industry with the most types of interfaces. Not counting I/O interfaces, the interfaces that connect to computers include USB interfaces and FireWire interfaces. There are three types of PCIe interfaces.

The USB 2.0 interface is the most familiar to everyone. In addition to Apple's latest MacBook notebook, other computers have it. The FireWire interface is more common on Apple computers, and other brands also have it, but relatively few. The transmission speed of these interfaces is generally around 480Mbps, and 64 sound tracks can be recorded simultaneously.

Be sure to pay attention to these three issues when purchasing a sound card

USB interface

(Picture source: Baidu)

Compared with USB interface Compared with the FireWire interface, the biggest advantage is that it can transmit audio data at a constant rate. When recording multiple channels at the same time, the FireWire sound card is more stable than the USB sound card, but as mentioned above, it is equipped with a FireWire interface. There are too few computers.

Be sure to pay attention to these three issues when purchasing a sound card

FireWire interface

(Picture source: Baidu)

In addition to USB and FireWire interface, there is also a PCIe interface. PCIe is an interface inside the computer that is directly connected to the motherboard, so it cannot be used on laptops. PCIe sound cards are usually used by very professional people. They can reduce delays, increase bandwidth, and effectively improve recording quality. Of course, more professional equipment will be more expensive.

Page 3: The main technical parameters of the sound card

The main technical parameters of the sound card

When purchasing a sound card, what everyone is most concerned about is the sampling rate and sampling bits After counting, these two parameters are indeed very important and will directly affect the audio quality.

Let’s talk about the number of sampling bits first. In the audio industry, the number of sampling bits has a considerable impact on sound quality. There is a formula: 1bit=6dB. That is to say, audio with 16 sampling bits has a dynamic range of 96dB. The digital noise floor is very high and the dynamic range is very small. This causes obvious noise to be heard in relatively gentle and quiet music when the number of audio sampling bits is 16 bits.

Be sure to pay attention to these three issues when purchasing a sound card

Recording waveform chart

(Picture source: Baidu)

If it is 24bit For audio, if the dynamic range can reach 144dB, you can get better results. Because of this, 24-bit sampling is considered a professional standard and is widely promoted.

The sampling rate is a relatively subjective parameter. For example, the quality of a CD is 44.1KHz, which means that 44,100 sampling points are taken per second, which is equivalent to giving the next 1 second The music of the bell, 44,100 photos were taken. When converting a digital signal into an analog signal, a waveform requires at least two sampling points, during which a phase difference can be obtained. Therefore, the sampling rate of 44.1KHz can accurately restore the signal with a higher frequency of 22.05KHz.

The sampling limit of the human ear is 20KHz, so 44.1KHz is enough to capture and restore sound. However, some professional sound cards will choose to work at 48KHz, 96KHz or even 192KHz. This is mainly due to some technical considerations and using a higher sampling rate to capture some useful sounds.

Choosing a sound card is a very professional matter. Although there may not seem to be many aspects to consider, each indicator determines the quality of recording this sound card can bring you. When purchasing, , don’t be lazy, you must consider everything in place, so that you don’t buy the wrong thing.