Amplifier Circuit Design
Amplifiers preamp circuit analysisAmplifiers preamp circuit is the input signal to direct the coordination of processing, from pre-amplification and the implementation of sound regulation and control circuit. Looking at the first stage circuit current amplifiers in which the input stage are basically used for pre-amplification unit op-amp, tone control section there are negative feedback-type and attenuation of the sub-type. Both the traditional tone control circuit and the current high standards of public address requirements lag. Different intensity of input signal source to conduct the function of a lack of coordination and handling of conversion is a megaphone front-end circuit design, there is another major issue.From the sound effects of regulation and control perspective, the EQ control range and compensation effects are the best, so many users, when using the amplifiers are amplifiers with a platform before the equalizer to enhance the regulation of sound effects. However, the current balanced output signal is stronger, has possessed the ability to direct-drive amplifier circuits, therefore, to undertake equalizer output signal accurately for the next one should be the volume potentiometer with only the pure power amplifier circuit. Therefore, after a balanced treatment of the audio signals from the amplifiers should not be the first-level input at input amplification. This is a lot of amplifiers manufacturers seem to think, so most of the before and after the class combined-type amplifiers are equipped with dedicated input equalizer, it is regrettable is the fact that a balanced input amplifiers tend to have chosen the wrong position, but the equalizer misquotation of the output signal to its former level in a certain part of the active input-point input level prior to the re-amplification, resulting in the use of a balanced input from the equalizer input overload distortion occurs when the adverse consequences.Some before and after the so-called split-level amplifiers, the front-end circuit an independent body, anatomy of which front-end circuit, it is but a simple tone control circuitry only the actual use must also be added with EQ to get a better PA effect. Amplifiers of the front-end circuit preferably form a balanced circuit design, such a front-end circuit in one step, users can cut with an additional link with the equalizer. The strength of a variety of different sources, it must be coordinated in the functional switch manage its various signals input intensity, too strong signal attenuation appropriate, or large weak amplification of the signal to take the necessary measures, in order to get the same intensity of the input signal, the basic method is to coordinate treatment.Now Sound configuration has tended to separate the various modules of the audio equipment to buy, combined matching direction. The subjects of the technical requirements for audio equipment format, which conforms to this consumer demand and achieve systematic development of China-made professional audio equipment, the only way out of specification operation. Here is not formatted to form the same circuit design, but the technical requirements, some of which interface should match. Like radio head, the popular models on the market, some output signal is 103mV, and some of 150mV, 380mV and so on, so different manufacturers go their separate ways for the radio function of the input amplifiers designed to be a reasonable increase in difficulty. If the radio signal output intensity of the first set at 150mV, so that amplifiers can be the best match the radio input circuit set at 150mV input point, consumers go to buy separately, it would not have to worry about the matching.