How Do I Choose the Best USB Sound Card?

A USB sound card is a sound card that is connected to a computer system through a USB bus. Common styles include a U disk shape that is easy to use and a box shape that is placed on the desktop. ^[1-2]

USB sound card is an external sound card. Its USB cable has four strands in use, two of which are used to get power from the host, and the other two are information data cables.

The sound card's role in the computer is relatively independent, and the overall performance of the computer is relatively small. But as part of a multimedia computer, the sound card determines the expressiveness of the sound. Compared with the sound card adopting the ISA bus structure, the sound card adopting the PCI bus structure has a larger data flow and a smaller system resource occupation rate. It also has a more delicate sound performance effect, which can make the computer music sound performance more realistic and natural. . ^[3]

The structure of a USB sound card is very simple: a USB interface, a set of output coupling circuits, audio signal output interfaces, input interfaces, a main chip and a crystal oscillator that provides him with a standard clock signal. Codec (codec) converts the digital audio signal output from the main chip into an analog audio signal that can be output, and the input power amplifier drives the speaker; at the same time, it is also responsible for converting the analog audio signal input from the sound card into a digital audio signal. sound. In theory, the output from Codec is already an analog audio signal, which can be directly output. However, because the sound card is designed with a single power supply, the signal output by Codec contains a large number of DC signals. These signals are meaningless and noisy. It must be removed before it can be output. And in the analog circuit part of the sound card, due to the poor anti-interference ability, it is necessary to use a special anti-interference circuit to deal with, this circuit is a coupling circuit. The dense capacitors and resistors on the sound card are mostly part of the so-called "resistance-capacitance coupling" circuit. Their role is to block the direct current from passing between the two circuit parts, and let the meaningful alternating current containing audio signals pass. Use this circuit to filter out unwanted DC signals and output valid AC signals through the audio output port. ^[3]

The simplest USB sound card is just an external AC'97 soft sound card. When the USB interface is inserted, the system will automatically recognize that it is AC'97 Codec, and then automatically set it as a USB AC'97 controller, everything is the same as the onboard AC'97 soft sound card.

Some USB sound cards have added new circuits to support more powerful functions such as multi-channel output and digital input and output. For example, the Maya 5.1 USB sound card is the same as those onboard sound cards that support multi-channel and DSP functions. , Need to install the driver of Codec chip separately. ^[3]

Sound Blaster Extigy

The Sound Blaster Extigy USB sound card uses an ultra-luxury design never seen before, uses an independent hardware audio chip, uses independent power supply, supports analog and digital audio input / output, and supports AC3 audio decoding and 5.1-channel output. With remote control.

This is still the most innovative and high-end USB sound card with the best sound quality. Tests show that the Sound Blaster Extigy outperforms the contemporary PCI sound card. However, the powerful audio processing capability of this sound card is limited by the speed of the USB1.1 interface it uses, the CPU usage is very high, and the features it supports are much less than those of contemporary PCI sound cards. Due to the above advantages and disadvantages, users who buy this sound card often do not use him as a sound card, but instead use it as a decoder / mixer for computer audio systems. ^[4]

Sound Blaster Audigy 2 NX

AUDIGY 2 series is the latest USB external sound card. Sound Blaster Audigy 2 NX is not as good as Sound Blaster Extigy in terms of sound quality. Instead, it uses a small, compact form factor that is more suitable for computer use, and its functions are more entertainment.

Sound Blaster Audigy 2 NX supports 7.1-channel output and DVDAUDIO decoding, adopts high-speed USB2.0 interface, supports most functions of AUDIGY2 sound card, and the CPU usage is much lower than Extigy.

All this makes the Sound Blaster Audigy 2 NX a far more powerful and sound card product than the SoundBlaster Extigy, and is more suitable for ordinary laptop users. However, the sound quality of the Sound BlasterAudigy 2 NX is indeed not the best. Because of its compact structure, the power supply and shielding design are worse than Extigy, and the quality of connectors and potentiometers is also lower than Extigy. Top-level PCI sound card, and not as good as Extigy. ^[4]

Digital Music LX USB sound card

Digital Music LX sound card is an innovative product for mid-to-low-end users. The transmission interface is USB1.1, which meets the general two-channel data transmission without any obstacles. It adopts USB direct power supply, which eliminates the need for an external power supply and is very convenient to carry, which is more suitable for some notebook users. This USB sound card is only 119 mm × 69 mm × 26 mm in appearance and weighs only 116 g. The sound card has some changes in the extended design, but it still has perfect I / O capabilities, and includes the functions of the built-in sound card, such as line in, line out, optical output, headphone output, and manual volume control. In addition, because it is an external independent sound card, the surface has non-slip teeth with good touch, and the volume can be adjusted manually, which is very convenient to operate and control.

The sound card has an optical fiber output function, and a toggle switch on the side is used to convert between analog output or digital output. Bass enhancement function, 10-band equalization adjustment function to enhance MP3 music listening experience. This sound card uses the innovative and patented CSMM 3D technology to experience 5.1 surround sound in stereo headphones. ^[4]

RCA and S / PDIF output and stereo RCA input are provided at the interface. The S / PDIF digital input and output are important for home theater-based sound cards, because the requirements for DVD digital sound effects include AC3 / DTS and other technologies. It is completed by S / PDIF digital input and output interface. In addition, to ensure good output and input quality, Digital Music LX uses RCA sockets for connection, and the reliable contact can ensure the sound quality to the greatest extent. Relatively speaking, the sound quality of Digital Music is poor, basically similar to ordinary mid-range sound cards such as VIBRA 128, but stronger than many notebook / quasi-system onboard sound cards.

A880 USB sound card

The A880 USB mobile sound card uses the world's mainstream USB mobile digital sound solution, including advanced audio technology, and comprehensively upgrades sound quality, sound effects, rhythm, vocal recording and other functions. This sound card has a very small appearance, about the size of an ordinary flash disk, and has a power indicator, mute and volume increase and decrease buttons on the panel. ^[1]

The functionality of the A880 USB sound card is also excellent. Using advanced multi-channel technology, it breaks through the two-channel sound mode of traditional sound cards to achieve extremely realistic virtual 5.1-channel dynamic sound effects. In addition, the positions of five analog speakers can be freely adjusted to enhance user participation. In addition, the A880 sound card also uses the most advanced Xear 3D technology, fully supports MS DirectX, EAX1.0 / 2.0, HRTF 3DX functions, provides a variety of mixing, rhythm, sound field and other modes and 23 real-world sound field preset modes, Make the music scene richer, more natural, and the sound quality is realistic, which meets the needs of game players to pursue the effect of sound identification. ^[4]

There is a headphone jack and a microphone jack at the end of the sound card. The microphone can be used to realize the recording function through software settings, and you can use the MTV to sing karaoke on the computer. The function is stronger than the ordinary USB sound card. The A880 USB mobile sound card application crowd is mainly some gamers. Due to its small size and can be carried around, it uses the USB 2.0 interface, which effectively solves the speed bottleneck problem of the previous generation USB sound card. ^[4]