Notebook sound card audio solutions articles
The past two years more and more users are beginning to realize the benefits of portable, laptop computer sales momentum and therefore can not block stiffness. Laptops in the past has been to office systems to appear, there are many companies starting to focus on its entertainment, but audio performance Sony VGP-BPL2 Battery still not satisfactory. To keep the sound to become the bottleneck of entertainment notebooks, we have created the topic dedicated to those who like games and video entertainment notebook users. This topic is divided into three parts, including: laptop sound card, speakers and headphones, let us first look at notebook sound card. Why are hard to break the audio quality?
Notebook audio quality is difficult to break through the main reason why the term is limited to the size of notebook computers. In fact, the built-in sound card notebook, especially the latest Sonoma platform, the quality of the audio chip is sufficient to meet the everyday needs of most users. But because the size limit, the internal structure of very compact laptop, the audio part of the circuit and other circuits are also close together, like, want to achieve good anti-electromagnetic interference effects is very difficult, in many notebook computers using high-quality codec chip is no good.
On the other hand, notebook computers can only try small speaker and speaker box is not enough space, it is difficult to play out the speaker should have the effect, to say nothing of the bass. Like in some well-designed high-end notebook computers use a 4.1 sound system, but the effect is still far from a desktop PC. And because laptops are usually only the headphone jack, so even with well-designed audio circuitry, can not external speakers for better sound quality.
Go?
For desktop machines, the majority of users will opt out of cost considerations and will not sound better to consider an independent board sound card, so a huge price difference and the relatively small difference in sound quality so that most people can not accept an independent sound card . Although the desktop machine and sound card there are circuit design and anti-electromagnetic interference, but much smaller than notebooks, even one not understand the audio of people can easily feel out of the rough notebook audio.
Transformation of laptop audio, of course start from the core of the sound card, but limited to the laptop itself features built-in sound card is difficult to achieve high standards, HP pavilion dv9000 Battery audio manufacturers have seen this, have introduced USB, IEEE1394 and PCMCIA interface to the external sound card. Notebook audio design is not a breakthrough, we only rely on these products to improve the quality of their audio output.
It is worth noting, however, this part is more for games and music lovers, enthusiasts and even professionals, because they are harsh audio quality requirements. For ordinary users, the majority of high-quality laptop audio output quality is acceptable, then these users should be concerned about is that we will be gradually introduced after the two laptop speakers and headphones products.
What is the AC "97?
Currently, the majority of notebook computers with line AC "97 standard integrated sound card, the chip most of the ESS, Creative, Realtek, and Yamaha offer, of which the most widely used products Realtek, then what is the AC" 97 what?
In 1996, by Intel, Innovation, NS, Analog Device, and Yamaha and other manufacturers jointly presented 5 Audio Codec "97 (referred to as AC" 97) audio standards. From the initial to the current two-channel 8-channel, AC "97 After a total of 4 times the major changes.
AC "97 1.x: fixed 48kHz sample output; AC" 97 2.1: expanded part of the audio features, began to support a variety of multi-channel sampling rate of output and output; AC "97 2.2: improved and extended some of the audio features began to support S / PDIF output (Sony / Philips Digital Interface, Sony Philips Digital Interface); HD-Audio: Intel latest audio standards used in place of AC "97, supports up to 7.1 surround output, and has 32bit/192kHz of high targets, now based on the new Centrino platform notebook on the use of such audio standards.
When it comes to AC "97, many people will have a misconception that AC" 97 refers to the soft sound card, sound card is in fact now follows the AC "97 standard. The soft sound card because the codec work outside the exchange to the CPU to process sound card which omitted many of the original hardware. in the initial stage, the soft sound card, most people are skeptical, to eliminate the user's concern that such products, although simplifying the hardware but still meet the AC "97 standard Therefore manufacturers have highlighted the soft sound card is AC "97's. Over time, many people put AC" 97 sound card as a synonym of soft.
Test Description
The test uses the latest release of the new Asus Centrino laptops, software and hardware configurations shown below. Objective test used RMAA 5.5 (RightMark Audio Analyzer) test software, Dell Inspiron 6000 Battery the audio cable required for use of the Diamond Monster Sound MX200 sound card in the included audio test line. The most common test used 16bit 44.1kHz sampling rate standards.
Test platform configuration table
Hardware platform
ASUS W5000A CPU Pentium M 770
Chipset i915GM
Memory DDR2-400 768MB
Software Environment Operating System Windows XP + SP2 Chinese version of the sound card driver SB Live! 24bit External
Audigy2 ZS Notebook
TerraTec AudiMax 5.1 USB v1.0 INDIGO io
TerraTec Aureon 7.1 FireWire
RMAA is how to assess the sound card?
Before the test, of course you want to install sound card driver, then the audio test line to the sound card "Line out" and "Line in" Interface connected to form a closed loop, then you can begin testing. The test software is a simple test the audio output sound card, enter the property, do not do testing of various audio effects, so test drive before you turn off the 3D sound effects, sound effects and other environmental effects. RMAA test results, including frequency response, noise level, dynamic range, total harmonic distortion, intermodulation distortion and stereo separation and so on, following the brief overview of the implications of these projects.
Frequency Response (Frequency response)
Good frequency response at each frequency point can output adequate and stable signal, between different frequency points, the signal size should be the same. However, in practice some of the low and high frequency, signal reconstruction is difficult, so most of these two intervals will produce sound attenuation, but to different degrees. Results from the test curve point of view, the better the sound card output quality, the more flat frequency response curve, and the attenuation of the band closer at both ends of the horizontal axis.
Noise level (Noise level)
This test is mainly the sound card of anti-interference ability test, the results can reflect the level of the sound card analog circuit design. The results show a low frequency to HP pavilion DV6 battery frequency sound card from the distribution of noise. Graphic in the lower position on the vertical axis, the better the smaller amplitude.
Dynamic Range (Dynamic range)
Dynamic range is the maximum value of non-distorted signal and noise ratio, where noise is no signal output value, the better the value of dynamic range. Usually the industry used to use the-60dB signal to detect the target, because the output level close to full load, THD (total harmonic distortion) will be relatively poor performance, then overwrites the original harmonic generated noise exists, thus affecting test results. The test scores for those who like to enjoy music and video discs of the user is particularly important.
THD (Total Harmonic Distortion)
Total harmonic distortion referred to as THD. Generated from the original signal frequency of the formation of new non-linear distortion. All are collectively referred to as nonlinear distortion of the frequency harmonics (Harmonic), the production of these harmonic frequencies are integer multiples of the original signal frequency. For example, 1000Hz harmonic on 2kHz, 3kHz and 4kHz and other locations. Total harmonic distortion is used to examine the results of nonlinear distortion, the smaller the value the better.
IMD (Intermodulation Distortion)
Intermodulation distortion is a method of measuring nonlinear distortion. Intermodulation distortion from the two frequency F1 and F2 in F1 + F2 and F1-F2 when the harmonics generated by these harmonics to each other but also through and, worse to generate new frequencies. Such as 12kHz and 13kHz frequency of the harmonic distortion include 1kHz and 25kHz, and 1kHz and 12kHz can mix up the frequency of 13kHz and 11kHz, and so produce more harmonics. Harmonic measure the size of these locations is the intermodulation distortion.
Stereo Separation (Stereo crosstalk)
This test will detect the left (right) channel audio, "leakage" to the right (left) channel conditions, in the digital signal you want to be 100% of the left and right channel separation is a very simple thing, but we final hearing is analog signals, analog signals can not Dell Inspiron 500m battery this ideal state is almost always produce some Crosstalk (Crosstalk). The results observed curve, the intersection of two curves less appointment.
