1) selection, broadcasting and video conferencing applications should use broadcast products, monitoring applications can use monitoring products, VGA signal (some people regard it as a video) to use VGA signal matrix.
2) size: in a project, the audio signals and video signals and VGA signals as three different media. General audio signal input quantity, such as microphone and CD and DVD audio, but considering the power amplifier and audio only one set up in general, plus a power amplifier before the mixer for mixing, there may be a need for several signals, so the audio matrix output is not very large, such as 8 or 32 * 64 x 8, but no need to choose 32 x 32 or 64 x 64, unless it is broadcasting and video conference transmission, each video will have audio synchronous transmission.
In the design, the number of source signals is easier to determine the number of signal sources, have a look, the number of input matrix is set up, but to consider the number of independent output channels, which is based on the operation mode of the system and, sometimes there may be a few Taiwan showed that only the distribution relationship between devices (uniform, never independently) then you can take up a port and distributor, if these devices are likely to be independent, but each accounted for an independent output better.
In many cases, the number of input and output is very large, if a large matrix, cost will be higher (the matrix is bigger and more difficult to, the cost is also higher) can consider whether to use packet, such as surveillance, can show some wall display device displays only the signal of a certain region, and other equipment respectively display signals of other specific areas, so it can be divided into large matrix matrix of small scale (such as 128 x 64 divided into 4 sets of 32 * 16) if there may be a need for each other between the districts of signal.
Matrix switch as a part of the transmission system, the main problems in my project in the common problems and solutions ", the principle is the same, is nothing but the mechanism of several generation, as long as the phenomenon of distinguish, the direction should be no big problem. The special point is to use a small matrix composed of large-scale problems, for example: in the 64 * 32 128 * 32, two * 32 * 64 64 128 cannot be used, or the use of the concept and application of packet, three sets of 64 * 32 128 * 32, this is the concept of full matrix therefore, when used in combination should distinguish the packet and use of the whole matrix (the matrix refers to each output port can select, in all input and independent of each other).
3) the choice of production matrix manufacturers of many manufacturers, the nominal index is different, because this kind of device is not a laboratory prototype, but engineering applications, so the applicability and reliability issues is very important. The project site is different, need through continuous engineering inspection in the mature process of products, found the problems needed to be improved, so the mature process of products is relatively long, common situation is: in the scene, the use of certain brands of products, some technical problems will appear in engineering, and other brand products after the problem can be solved, not a brand products have large errors, but it is not a brand products, generally speaking, is not enough to pay the tuition, the problems are not enough, the product design is ill considered, so choose the company specializing in the production of products, because its products have been relatively mature.
The nominal index of manufacturers, especially VGA signal products, matrix display equipment is the core, if the problem is a global problem, will make the whole system paralysis, so stability and reliability is overwhelming, like the price is a little high, even with a low index, but also to ensure stable and reliable.
Technical support, strange encountered in engineering field, factory technical support is a very important indicator, independent R & D capability, mechanism of the problem has a correct understanding of products, strong applicability, stable and reliable, has the strong ability of the scene to solve the cooperation of the manufacturers.