Nowadays, wired microphones are rarely used on the stage. They are generally wireless or professional microphones. Passive audio equipment is also used more and more widely in people’s daily lives. Here is an introduction to wireless microphones. Which types and how to choose wireless microphones
Wireless microphone type
1. Distinguish according to the transmitting frequency:
a. FM wireless microphone: commonly known as FM refers to FM
88-108MHz international FM broadcasting frequency band. Early consumer wireless microphones used FM radios to receive. The system was simple and low-cost. However, due to the effects of use, it failed to meet the requirements of professional quality. At present, it can only be used as a toy for children or students.
b. VHF wireless microphone: It is divided into two types, low frequency and high frequency. The former uses the VHF50MHz frequency band. Due to the low frequency, the antenna length is too long, and it is most susceptible to interference from various electrical clutter. Therefore, this type of Products have been replaced by high frequency bands and gradually disappeared from the market. The latter uses the VHF200MHz frequency band. Because of the higher frequency, the antenna is shorter, and it can even be designed as a hidden antenna, which is convenient, safe and beautiful. The clutter interference of the receiver is greatly reduced, the circuit design is extremely mature, and the parts are popular at a price. Low cost, so it has become a popular model on the market today.
2. Distinguish according to the oscillation mode:
a. Quartz lock (Qualtz
Locked) Model: A quartz oscillator is used to generate a precise and stable fixed frequency for transmitting and receiving. The circuit is simple and the cost is low. It is the standard circuit design of today's wireless microphones. This type of microphone and receiver can only be paired with a single frequency, and the frequency cannot be changed or adjusted.
b. Phase locked frequency synthesis (PLL
Synthesized) model: In order to avoid the wireless microphone from encountering interference from other signals in use, or to use multiple microphones at the same time, it is necessary to change the channel conveniently and quickly at any time, so the PLL circuit design is used to achieve This feature is required.
3. Distinguish according to the receiving method:
a. Automatic selection of receiving wireless microphone system (True diversity receiving wireless system): due to the physical phenomenon of "dead-point" (dead-point) in the radio waves, the sound output of the receiver will produce intermittent or unstable shortcomings. To solve this defect, professional models must adopt the "Automatic Switching Diversity Receiving" method with dual antennas and dual tuners to improve.
b. Non-diversity receiving wireless microphone system (Non-diversity receiving wireless system): Due to the complicated and precise circuit design of the above models, it is difficult to assemble, and the cost is high. Generally, low-cost models do not adopt the design of automatic selection. , So it is impossible to eliminate the shortcomings of sound interruption caused by wireless microphones in use. Of course, this type of machine cannot meet the basic requirements for professional use.
4. Distinguish according to the number of receiver channels:
a. Single-channel model: A non-automatic or automatic selection receiver with only one channel installed in a receiver chassis. The former has almost no market in Taiwan, but because of the cheapest price in the export market, it is one item ( Big color goods). The latter is the best model suitable for simultaneous use of multiple channels in professional situations due to its simple use and stable characteristics to avoid signal interference.
b. Dual-channel model: In the case of a receiver, two-channel non-automatic selection or automatic selection receivers are equipped to make full use of the space of the case and reduce costs. The former is the so-called "Asian fighter jet" model, because of its simple design, it has become the main model for Taiwan's mass-produced low-priced manufacturers. The latter is not easy to deal with internal interference and antenna mixing and matching because of its complicated mechanism and circuit. It is only available for a few manufacturers that produce professional models.
c. Multi-channel model: In the case of a receiver, receivers with more than four channels are assembled, and most of them adopt the mechanical design of modular receiving modules. It is mainly suitable for the use occasions of rack-mounted professional models.
Wireless microphone purchase
The technical strength of the manufacturer determines the quality of the product
Wireless microphones are the result of combining speakers and wireless communication technology. They are completely different from the technology and equipment used to manufacture wired microphones. Therefore, wired microphone manufacturers who also manufacture "microphones" may not be able to manufacture wireless microphones unless they continue to manufacture wireless microphones. Innovative, manufacturers of wireless communication products may not be able to manufacture good wireless microphones. Only manufacturers with long-term professional audio technology and wireless high-frequency technology background can produce good wireless microphones. The biggest difference between wireless microphone products and other wired products is that the use effect is very closely affected by environmental conditions. Therefore, a high-quality wireless microphone cannot be designed in the laboratory in a short period of time. It also requires long-term contact with users. After actual use in a variety of different environments, the gains and losses are given back to the design engineer, and after continuous non-development and improvement, a truly perfect product can be manufactured. Therefore, to choose a good wireless microphone product, you must choose a professional technical background and long-term manufacturing experience.
Data collection and evaluation
The most basic sources of information for purchasing products are catalogs and magazine advertisements provided by manufacturers. However, generally small-scale manufacturers with incomplete equipment cannot provide correct values at all, so consumers cannot understand, analyze and compare from catalogs. Some manufacturers even use catalogs and advertisements to exaggerate facts and mislead consumers' psychology. However, quality is not spoken by the mouth, but is manufactured. Smart consumers can obtain the correct quality evaluation by carefully analyzing the actual products of the manufacturer, actual testing, and relative comparison in today's advanced information technology.
The choice between price and quality
In the recent period, the quality of wireless microphones made in Taiwan has been significantly improved due to the improvement of consumer requirements: the price has dropped greatly due to fierce competition from manufacturers. Because of survival, all small-scale manufacturers fought a price war with other big manufacturers in order to win orders. The saying goes: "One penny, one share". Consumers are often greedy for a little cheaper price. Instead, they bought products of poor quality. Some consumers are either too superstitious about famous brands or misled by manufacturers' false advertisements. So that the money spent is not worth the fare. How to choose cost-effective products, first is to understand your own needs, and second, you need to know the pros and cons of wireless microphone products, so that you can choose the most satisfactory product.