Here are the steps to format a hard drive on Windows, Linux, and Mac systems:

 

Windows:

1. Open Disk Management:

Press Windows + X and select "Disk Management" from the menu.

2. Select the Drive:

Locate the drive you want to format in the list. Right-click on it and choose "Format."

3. Configure Format Options:

In the Format dialog, choose the file system (e.g., NTFS, exFAT) and set a volume label if desired.

4. Complete the Format:

Click "OK" to start formatting the drive.

Linux:

1. Open Terminal:

Use a terminal application on your Linux distribution.

2. Identify the Drive:

Type lsblk to list all available drives and partitions. Note the drive's name (e.g., /dev/sdb).

3. Unmount the Drive (if necessary):

Use sudo umount /dev/sdX1 (replace sdX1 with the appropriate partition identifier).

4. Format the Drive:

Use a command like sudo mkfs.ext4 /dev/sdX to format the drive. Replace ext4 with your preferred file system.

5. Verify:

Use lsblk again to verify the drive is formatted.

Mac:

1. Open Disk Utility:

Go to "Applications" > "Utilities" > "Disk Utility."

2. Select the Drive:

Choose the drive you want to format from the sidebar.

3. Erase the Drive:

Click "Erase" at the top of the window.

4. Configure Format Options:

Choose the file system (e.g., APFS, Mac OS Extended) and provide a name for the drive.

5. Complete the Erase:

Click "Erase" to format the drive.

Each operating system has specific tools and options available for formatting drives, and the steps can vary slightly depending on the version of the OS you are using. Always ensure to back up any important data before proceeding with formatting, as this process will erase all data on the drive.

When considering upgrading your device's SSD (Solid State Drive) capacity, weighing several factors is important. 

Storage Needs:

If you have a lot of files, such as large video files, games, or extensive software applications, a larger SSD will accommodate your data without needing to manage storage constantly. For users with minimal storage needs, a smaller SSD might suffice.

Performance:

Generally, larger SSDs can offer better performance. This is because they often have more NAND flash memory chips, which can enable higher parallelism and faster read/write speeds. However, the performance difference might not be noticeable for everyday tasks.

Cost:

Larger SSDs are more expensive. Consider your budget and whether your storage needs and usage justify the additional cost.

Longevity and Durability:

SSDs have a lifespan based on write cycles. Larger SSDs can potentially last longer because the wear is distributed over more memory cells. This can be a consideration if you frequently write large amounts of data to the drive.

System Requirements:

Consider the requirements of your specific device. A larger capacity drive may be physically too large or incompatible with some laptops or desktops.

Yes, you can use an NVR (Network Video Recorder) as a PoE (Power over Ethernet) switch, but it depends on the specific model and setup. Many modern NVRs come with built-in PoE ports, which allow them to directly power and connect to IP cameras. Here are some important points to consider:

 

Compatibility: Ensure your NVR and IP cameras are compatible and support PoE functionality. The cameras should be PoE-enabled to receive power and data through the network cables.

 

Number of Ports: Check the number of PoE ports available on your NVR. This will determine how many cameras you can connect directly to it.

 

Configuration: You may need to configure your NVR to recognize and manage the connected cameras. This often involves setting up the network and camera settings through the NVR's interface.

 

Power Supply: The NVR must support the power requirements of all connected devices. Ensure that the total power consumption does not exceed the NVR’s PoE capacity.

 

Network Layout: Using an NVR with PoE ports can simplify your network layout by reducing the need for additional switches. Ensure your network setup allows for efficient data flow and management.

 

If your NVR does not have PoE capabilities, you cannot use it as a PoE switch and will need a separate PoE switch to connect your IP cameras.

The Mini DisplayPort (MiniDP or mDP) is a compact version of the DisplayPort interface, designed to transmit both video and audio signals. Introduced by Apple in October 2008, Mini DisplayPort quickly became a standard feature in many Apple devices, including MacBook, MacBook Air, and MacBook Pro. It was developed to replace older connections like the Mini-DVI and Micro-DVI, offering improved capabilities and a smaller form factor.

Key Features of Mini DisplayPort:

Compact Design: The Mini DisplayPort is significantly smaller than the standard DisplayPort, making it an ideal choice for sleek and portable devices. Its small size does not compromise its functionality, as it can still support high-resolution displays.

High-Resolution Support: Initially, Mini DisplayPort could drive displays with resolutions up to 2560 × 1600 (WQXGA). With advancements in the DisplayPort standard, it now supports resolutions up to 4096 × 2160 (4K), providing crisp and clear video output5.

Versatility and Compatibility: While Mini DisplayPort connectors are commonly found on Apple devices, other manufacturers also use them. The port can carry video and audio signals, allowing a single cable solution to connect computers to monitors or TVs.

Thunderbolt Compatibility: The Thunderbolt and Thunderbolt 2 interfaces used the Mini DisplayPort connector. This allowed for high-speed data transfer alongside video and audio transmission.

Usage and Applications:

Mini DisplayPort is widely used in professional and consumer electronics because it delivers high-quality audio and video signals. It's a popular choice for connecting laptops to external displays, projectors, and other video equipment.

HDCP, or High-bandwidth Digital Content Protection, is a technology developed by Intel to protect digital audio and video signals from being illegally copied. It applies to high-bandwidth digital signal interfaces such as DVI, HDMI, DP, UDI (Unified Display Interface), and GVIF (Giga-bit

Video Interface).

HDCP is designed to prevent HDCP-encrypted content from being played on unauthorized devices. Before sending signal data at the signal end, the signal device will check whether HDCP has authorized the receiver to obtain the right to receive data. It will only send encrypted signal data after confirming that it is a legal device.

To manufacture devices that can play HDCP-protected content, manufacturers must obtain patent licenses from Intel's subsidiary DCP-LLC (Digital Content Protection LLC), pay annual fees, and meet various conditions, such as the device cannot copy protected content or transmit protected content to other unauthorized devices.

With the iteration of HDCP versions, its version has been updated to version 2.3. Currently, the most common devices still support versions 1.4 and 2.2.

The term "3C product" typically refers to products in the categories of computers, communications, and consumer electronics. These are often seen as the main pillars of the technology and electronics industry. Examples include:

Computers: Laptops, desktops, tablets, and related peripherals like keyboards and mice.

Communications: Mobile phones, networking equipment like routers and modems, and communication accessories.

Consumer Electronics: Televisions, cameras, home audio systems, and wearable technology like smartwatches.

These products are characterized by rapid innovation and frequent updates, driven by consumer demand and technological advancements.

What does "USB male to female" mean?

"USB male to female" refers to a type of USB adapter or extension cable where one end has a male USB connector (plug) and the other end has a female USB connector (receptacle). This setup allows for extending the length of a USB connection or adapting it to fit different ports.

What is the purpose of a USB male-to-female adapter?

The primary purpose of this adapter is to extend the length of an existing USB cable. It can also be used to reposition USB ports to a more accessible location, making it easier to connect and disconnect devices.

How to use it?

To use a USB male-to-female adapter, plug the male end into a USB port on your computer or device, and then connect your USB device to the female end. This effectively extends the reach of your USB device.

Are there different types of adapters?

Yes, there are different types of USB male-to-female adapters corresponding to various USB standards, such as USB 2.0, USB 3.0, and USB-C. They vary in terms of data transfer speeds and power delivery capabilities.

Can I use a USB male-to-female adapter with any USB device?

Generally, a USB male-to-female adapter is compatible with any USB device. However, it is important to match the type of USB (e.g., USB 2.0, USB 3.0, or USB-C) to ensure proper functionality and optimal performance.

Is there a limit to how many USB male-to-female adapters I can use in a chain?

While you can connect multiple USB male-to-female adapters or extension cables in a chain, it is not recommended to exceed the maximum USB cable length (typically around 5 meters for USB 2.0 and 3 meters for USB 3.0) without using powered USB hubs or repeaters, as this can degrade performance and power delivery.

Can a USB male-to-female adapter support data transfer and power delivery?

 Yes, this type of adapter can support both data transfer and power delivery. The capabilities depend on the USB standard of the adapter. For example, USB 3.0 adapters support faster data transfer rates and higher power delivery compared to USB 2.0 adapters.

What are some common uses for USB male-to-female adapters?

Common uses for USB male-to-female adapters include extending the reach of USB devices like keyboards, mice, printers, and external hard drives; relocating USB ports to more convenient locations; and connecting USB devices to hard-to-reach ports on desktop computers or behind TV sets.

“UHD” is the abbreviation of Ultra High Definition, which means Ultra High Definition. The “UHD” standard proposal issued by the International Telecommunication Union (ITU) calls the display with a physical resolution of 3840×2160 (4K×2K) and above as ultra high definition. Under different standards, the resolution represented by UHD is different. For example, the common resolution of Full Aperture UHD in the film industry is 4096 x 3112 and Academy UHD is 3656×2664. Generally speaking, UHD TV is the standard issued by ITU.

FHD is called Full High Definition. In the internationally recognized standards, “HD” is defined as three standard forms of 720p, 1080i and 1080p. But FHD is 1920*1080p. There are two conditions for this standard: 1. the video vertical resolution exceeds 720p or 1080i; 2. the video aspect ratio is 16:9. “P” means progressive scanning and “I” means interlaced scanning. Generally speaking, 480*320, 640*480 are “standard definition”; 1024*720p, 1920*1080i are “high definition”; 1920*1080p is “full HD”; 3840*2160, 7680*4320 are “ultra HD” (UHD).

Then we can clearly see the difference between UHD and FHD. UHD is Ultra High Definition with a resolution of 3840×2160 and above and FHD is 1920×1080p. In terms of video resolution, UHD is at least 4 times higher than FHD. The previous difference is intuitive and can be distinguished with our eyes.

 

Tip:

16:9

HD 1280*720

FHD 1920*1080

QHD 2560*1440

UHD 3840x2160 (4K)

21:9

WFHD 2560*1080

WQHD 3440*1440

WUHD 5120*2160

DP/MDP Passive Dongle can provide Dual Mode signal in DP port

 

DP/MDP Active Dongle only can provide DP signal in DP port

 

DP Connector can provide Dual mode signal that means the DVI 

 

HDMI signal output can be exchanged by Passive dongle

 

DP Connector only can provide DP signal means the DVI HDMI 

 

signal output can be exchanged by Active dongle only

 

The example for AMD 5870 MDPx6

 

If need 3DVI display output

It needs 2PCS Passive Dongle + 1PC Active Dongle (As GPU only 

 

support 2 DUAL MODE signal)

 

If need 6DVI display output

It needs 2PCS Passive Dongle + 4PCS Active Dongle (As GPU only 

 

support 2 DUAL MODE signal)

The addition of the power delivery capability to USB Type-C effectively reduces the clutter of having to carry multiple cables and adapters for power, A/V, and data transfer. This additional specification allows for a theoretical 100W max charging power, which is sufficient to charge devices larger than tablets such as laptops. Power Delivery is in its infancy but will become more widely adopted as device manufactures and connectivity providers develop the technology. Not all USB-C cables or devices are capable of supporting USB PD. Always consult the specifications for your devices to confirm support for the PD (as well as the maxium charging power).

                              Table 2-1 USB Type-C Specification Release 1.3

Mode of Operation	Nominal Voltage	Maximum Current
USB 2.0	5V	500 mA
USB 3.1	5V	900 mA
USB BC 1.2	5V	Up to 1.5A
USB Type-C	5V	1.5A or 3A
USB PD	Configurable up to 20V	Configurable Up to 5A

For the first time, the USB-IF has allowed alternate protocols on their connectors to extend the capabilities of this connection. The addition of non-USB formats like DisplayPort, Thunderbolt 3, and MHL will allow devices to connect to displays and transfer data at higher speeds through a single USB-C cable. For example, Thunderbolt 3 can allow for bandwidth up to 40Gbps and support dual 4k displays @ 60Hz. This allows for ultra-fast data transfer to and from a Hard Drive or support for the latest TVs and monitors all in a compact adapter.
 
Not all USB Type-C cables or devices are capable of supporting these technologies. Always consult the specifications for your devices to confirm support for alternate modes. As an example, some laptops support Type-C but do not support Thunderbolt 3 or alternate modes. Computers and smartphones with USB-C 2.0 will not support alternate modes and thus, are not capable of transmitting video.

USB connector types multiplied as the specification progressed. The original USB specification detailed Type-A and Type-B plugs and receptacles. The USB Type-C Specification defines a new small reversible-plug connector for USB devices. The Type-C plug connects to both hosts and devices, replacing various Type-A and Type-B connectors and cables.

Not all USB-C ports support all features of USB-C. Some computers and smartphones support data only for flash drives while some others support video out and power as well.
Here is the list by manufacturer of computers and smartphones that support full feature USB-C:
Dell
Dell XPS 12 9250, 13 9350 / 9360 / 9365 / 9370, 15 9550 / 9560 / 9570 / 9575, Latitude 5290 / 5480 / 5580 / 7275 / 7280 / 7285 / 7290 / 7370 / 7380 / 7390 / 7480 / 7490 / 7520 / 7720 / E5570, Precision (certain configurations) 3520 / 15 3510 / 5510 / 5520 / M7510, 17 M7710, Alienware 13 / 15 / 17
Apple
2016 / 2017 / 2018 MacBook, MacBook Pro, iMac, iMac Pro
Acer
Aspire Switch 12 S / R13, V15 / V17 Nitro, TravelMate P648, Predator 15 / 17 / 17X, Chromebook R 13
ASUS
ROG GL / G5 / G7 / GX / Strix, ZenBook Pro UX501VW, ZenBook 3 Deluxe / Pro, Transformer 3 Pro, Schenker XMG, Q524UQ 2-in-1 15.6, Chromebook Flip C302
Gigabyte
Aorus X5 15, X7 DT 17, BRIX / BRIX S
EVGA
SC15 / SC17 Geforce GTX 1060
Google
Pixelbook / Pixelbook 2
HP
Elite X2 1012 G1 / G2, Z1 Workstation G3, Spectre 13.3 / x360, EliteBook 1040 G4 / X360 G2 / X 360 1020 G2 / Folio G1, ZBook 17 G3 / 17 G4 / 15 G3 / 15 G4 / Studio G3 / Studio G4 / Z2 G4 / Z4 G4 / Z6 G4 / Z8 G4, Chromebook 13 G1
Lenovo
Legion Y720, IdeaPad Y900, Miix 720, Thinkpad P 50/70, T 470 / 470S / 570, X270, X1 Carbon, X1 Yoga, Yoga 370 / 900 / 910, P50 / P51 / P51S / P70 / P71
MSI
Phantom / Phantom Pro, Ghost / Ghost Pro, Stealth / Stealth Pro, Titan / Titan Pro, Dominator / Dominator Pro, Vortex G65
Razer
Blade / Stealth / Pro
Samsung
NP900X5N, Notebook Odyssey, Notebook 9 15 Inch, Galaxy Note 9 / Note 8 / S9 / S9+ / S8 / S8+
HTC
HTC 10 / U11 / U12
LG
Gram 15Z970, LG G5 / V20 / V30
Intel
NUC6i7KYK / NUC7i5BNH / NUC7i5BNK / NUC7i7BNH / NUC6i7KY
Toshiba
Portege X20W / X20E / X30 / X30-E, Tecra X40 / X40E
Sony
VAIO S11
Clevo
P 750DM / 770DM / 870DM
FUJITSU
Workstation CELSIUS H760
Microsoft
Surface Book 2, Surface Go, Lumia 950 / 950 XL
Zotac
ZBOX / MI549 / MI552 / MI572 / MI553
Huawei
MateBook X Pro

Some computers such as the Lenovo Yoga 910 have more than one USB-C port and they have different functions. The picture below shows that one USB-C port (left) is a charging only port while the other USB-C port (right) supports video and data. Please make sure to plug in your USB-C adapter or docking station to the right USB-C port.
 
Some USB-C ports have the Thunderbolt technology built in to achieve all features offered by USB-C as well as higher data transfer rate and additional features offered by the Thunderbolt technology. Thunderbolt 3 ports support data, video and charging and usually have the Thunderbolt logo printed next to them. Below picture shows a Thunderbolt enabled USB-C port.
 
Below picture shows two USB-C ports on a Windows laptop. One USB-C port (left) supports Thunderbolt 3 and therefore offers the video, data, and charging capability. The other USB-C port (right) only supports data and charging without video capability. Please make sure to connect your USB-C / Thunderbolt 3 adapters and docks to the Thunderbolt 3 port on your laptop.
 
USB-C adapters and docks will work fine when plugged into a Thunderbolt 3 port on a laptop. However Thunderbolt 3 adapter and docks will not work when plugged into a USB-C port without the Thunderbolt capability. Refer to the article below for the list by manufacturer of computers that support Thunderbolt 3. Please contact the laptop manufacturer directly if you are not sure what kind of USB-C port your laptop has.

2.0 Version increases bandwidth to 18Gbps significantly. Also includes the following advanced features:
•Up to 1536kHz audio sample frequency for the highest audio fidelity
•Up to 32 audio channels for multi-dimensional immersive audio experience
•Resolutions: Up to 4K@50/60 (2160p), 4 times the clarity of 1080p/60 video resolution, for the ultimate video experience
•Dynamic synchronization of video and audio streams
•Support for the wide angle theatrical 21:9 video aspect ratio
•Simultaneous delivery of multi-stream audio to multiple users (Up to 4)
•Simultaneous delivery of dual video streams to multiple users on the same screen
•CEC extension provide more expanded command to control consumer electronics devices through a single control point

HDMI 2.0b is backwards compatible with earlier versions of the HDMI specification and the most recent update of the HDMI specification. Also enables key enhancements to support market requirements for enhancing the consumer video and audio experience.
 
What are the key advanced features enabled by HDMI 2.0b?
•Simultaneous delivery of dual video streams to multiple users on the same screen
•Simultaneous delivery of multi-stream audio to multiple users (Up to 4)
•Enables transmission of High Dynamic Range (HDR) video
•CEC extensions provide more expanded command and control of consumer electronics devices through a single control point
•Bandwidth up to 18Gbps
•4K@50/60 (2160p), which is 4 times the clarity of 1080p/60 video resolution
•Up to 32 audio channels for a multi-dimensional immersive audio experience
•Up to 1536kHz audio sample frequency for the highest audio fidelity
•Support for the wide angle theatrical 21:9 video aspect ratio
•Dynamic synchronization of video and audio streams
 
Current High Speed cables (Category 2 cables) are capable of carrying the increased bandwidth. HDMI 2.0b does not define new cables or new connectors. 

In the past the HDMI version number (for instance 1.3b or 1.4a) was used to mark cable products. This is not allowed any more because often suppliers marked products with wrong HDMI versions. The result was that customers often bought products in the believe that certain HDMI features are supported which was not always the case.
 
HDMI cables are only produced according to the following 4 HDMI cable specifications:
 
    • HDMI
    • Highspeed HDMI
    • HDMI with Ethernet
    • Highspeed HDMI with Ethernet
 
Please note that the a.m. HDMI cable specifications do not guarantee that a specific HDMI version is supported by every HDMI cable supplier/ trader. With KabelDirekt HDMI cables you are on the safe side that always the newest HDMI version is supported.
 
KabelDirekt HDMI cables are produced according to the standard Highspeed HDMI with Ethernet and are fully compatible with HDMI 2.0 (all available HDMI features as well as resolutions up to 4K in 3D are supported). The bandwidth of KabelDirekt HDMI cables is 18,2 GigaBit/ second.

Firstly please make sure that it is buildt in Speaker type display and the HDMI cable connect to the audio & video output interface correctly.
Secondly make sure that the display adapter driver is correct, and then you need to set the audio output as the HDMI output signal.
All of the above, If this does not resolve your problem, please contact Email:vcomnet@vcom.hk to get professional advice.

Firstly ensure that transmits image resolution & refresh rate are not higher than 3840*2160@30Hz/1920*1080@60Hz and the display adapter driver is correct , the display is open with HDMI signal source.
Secondly please connect the HDMI cable to the discrete graphics(if any) HDMI interface, if without discrete graphics, please replace other brand HDMI cable to operate under the same configuration. If it still doesn't work, please try to change the display.
All of the above, If this does not resolve your problem, please contact Email:vcomnet@vcom.hk to get professional advice.

1. I bought an HDMI cable, when connecting the PC motherboard port, no display, why?

Please plug the HDMI cable to the PC discrete graphics HDMI connector, and adjust the monitor signal source to HDMI.

 

2. I bought a DP cable, when connecting the PC motherboard port, no display, why?

Please plug DP line to PC discrete graphics DP connector, and adjust the monitor signal source to DP.

 

3. There are three colors on my motherboard USB ports, black, blue and blue-green, what are those ports?

Black: USB2.0; Blue USB3.0; Blue-green:USB3.1

 

4. Can the DVI and VGA be transformed?

Yes, but only DVI-I can.

 

5. Nowadays, why there is no standard VGA interface on the graphics card?

VGA port is an analog signal, nowadays it’s the time pursue for screen Sharpness, VGA has gradually been replaced by other more high-end digital port.

 

6. My monitor only has VGA port, but graphics card has no VGA, how can I make it work?

You need a converter cable.

 

7. I see VCOM has HDMI AM TO CM cable, what kinds of equipment usually use these cables? If I have bulk purchasing, who do I sell to?

HDMI C interfaces mainly use in digital cameras and notebooks and a few discrete graphics.

 

 

8. Why nowadays only has HDMI interface on TV?

HDMI interface is Hitachi, Panasonic, Philips, Silicon Image, Sony, Thomson and Toshiba 7 companies jointly launched, because of the strength of promoters, and earlier launch time determines the HDMI’s popularization.

1.What cables should I use for home audio devices under the environment of the current market？

HDMI 1.4V is enough for routine using and HDMI 2.OV is required for the current newly 4K.

 

2.What’s the English code of CCS、BC、CCA that shows on your specification?

They mean the quality and structure of cables. Copper-Clad Steel for CCS, 

Bare Copper for BC and Copper-Clad Aluminum for CCA.

 

3. I have bought DVI 24+5 from VCOM, but it can’t be plugged into the DVI port of my motherboard, may I know what’s the problem?

Pls make sure the port of motherboard is 24+5, if not, it definitely can’t be plugged into.

 

4. If I need 50M VGA cables for my engineer project, can VCOM brand 50m VGA cables work as usual?

Yes, of course.

 

5. Which is better for VGA cables of 3+4、3+6、3+8?

3+8 is the best, and then 3+6, and 3+4 is the last choose.

 

6. Why the screen was so fuzzy after the displayer connected with VGA cable?

Pls adjust the screen resolution to the best if it was short length VGA cable.

If you used long meter VGA, it is normal to have slightly fuzzy, trailing, ghost because this is the common problem of analog signal. 

 

7. I have bought a DVI cable and there was no image after I connected to the PC mainboard. What’s wrong?

Pls plug the DVI cable into the DVI interface of PC discrete graphics and adjust the display signal to DVI.

HDMI High Definition Oxygen-free copper wire
4N Oxygen-free copper material
 
4N Oxygen-free copper is high purity Oxygen-free copper, the material is free of Oxygen, also is free of deoxidizer residual copper ( Actually it is still has some micro-oxygen and some impurities ), the content of oxygen not more than 0.03%, total impurities not more than 0.05%, copper purity more than 99.95% based on the standard. According to the actual data test, the high purity Oxygen-free copper shows more delicate in display when compare with normal purity copper, it is not easy oxidation, can be used in every place, noise reduction, the capacity of keeping real color is better than purity copper. Therefore, 6N Oxygen-free copper is better than 4N Oxygen-free copper.

An excellent headphone can’t be decided whether is good or not by the external factor. Not represented by a kind of material and structure. It is perfect match under a modern electro acoustics, materials science, ergonomics and stereo aesthetic. ——《The evaluation of the headset》

The conclusion for an excellent headphone is coming from the objective testing and subjective of listen the music. The objective testing included curve frequency response, response curve, impedance curve, square wave test, intermediation distortion and so on.

The first we need to know the headphone is the characteristic of the headphone’s sound. The advantage of the headphone is small phase distortion, wide frequency response.

The first characteristic is head shadow effect:
What acoustic environment the headphone made is the nature cannot achieve, The waves of sound Nature are interacting with a person's head and ears before enter into the ear canal.  While most record is made for sound playback, audio and video on the two speakers even wiring due to these two reasons we use headphones will feel audio-visual form in the header, listening is not natural, easy to cause fatigue. Head shadow effect can be improved through the use of special physical structure; sound field simulation software and hardware in the market.

The second characteristic is Earphone of low frequency:
Under the low frequency section (40 hz - 20 hz) and ultra-low frequency (20 hz) is through the body of perception, the human ear is not sensitive to the spectrum. Headphones can perfect the replay this low frequency, but because the body cannot feel low frequency, can let a person feel the headset of low frequency. Intermediate frequency for the headset is a sensitive area, the music of the most abundant information, is also the most sensitive to the human ear.The design of the headset to treat intermediate frequency is cautious, some low-grade headphones its frequency response range is limited, but on the mention of intermediate frequency and low get bright and sharp tone and turbidity, powerful voice, caused the appearance of high frequency is good, long time listening to the headphones, will feel dull.

Good headphones sound should have the following features:
1. Bottom and pure, without any unpleasant "slash", "om", sound.
2. Good sense of balance, tone won’t too bright or too dark, however, low frequency energy distribution uniformity, high band fusion between natural and smooth, no abrupt and burr.
3. High frequency extension is good, exquisite and smooth.
4. Low frequency pe deep, clean, full, full of elasticity and strength, no fat and slow.
5. Intermediate frequency distortion tiny, transparent and warm, human kind nature, thickness, magnetic, literally dental and twang.
6. Good resolving power, rich details, small signal can also clear replay.
7. Has a good ability of acoustic field depicting sound field is open, the instrument is accurate, and stable and sound field in enough amount of information, and you won't feel empty.
8. There was no obvious compression, dynamic has a good sense of speed, no distortion or distortion under the volume is small.

Such a headset can perfect replay any type of music, and music have good like real degree, long-term use does not cause fatigue, can make the listener immersed in music.

This interface is based on PanalLink (an interface technology created by Silicon Image) and TMDS electrical protocol and works as a basic electrical connection. TMDS（transition minimized differential signaling）is a differential signaling mechanism which can code pixel data and then transmit the data via serial connection. Digital signals created by the video card are coded according to TMDS protocol, then transmitted to the receiver via TMDS channel by the transmitter and finally they reach the digital display equipment after decoding. A DVI display system includes a transmitter and a receiver. The transmitter is the source of signals and can be built in the chip of a video card or attached to the PCB of the video card as an additional chip, while the receiver is an electrical circuit on a display which can receive and decode digital signals as well as transmit them to the display circuit. Through the transmitter and the receiver, the signals sent from the video card turn into images on the display. 

     

VGA (video graphics array) interface is used to output analog signals on the video card. It is also called D-Sub interface. Though LCD(liquid crystal display) can directly receive digital signals, many low-end products still adopt VGA interface in order to match VGA-interfaced video card. VGA is a type D interface with fifteen pinholes in three rows. And there are five pinholes in each row. VGA is the most widely used interface type on video cards. The majority of video cards have this interface. 

     

HDMI (high-definition multimedia interface) is a brand new interface that transcends those audio-video splitting transmission interfaces of the past. Its transmission rate can reach a maximum of 5Gb/s. Besides,this interface can transmit image data and further more, it can simultaneously transmit audio signals up to eight sound channels. This non-compressed digital data transmission can effectively reduce signal interference and attenuation caused by data type conversion.