18051836期天津11选5 www.dsgog.icu First, let's talk about how to understand a horn unit, which is one of the most fundamental and most important issues to be faced by every manufacturer and speaker system designer. According to the actual production and engineering design in our country, we can understand the speaker unit from the following six aspects: objective physical characteristics. (Note: the subjective sense of hearing is another important method to recognize the horn unit. With the progress of science and technology, the description of the objective physical characteristics is becoming more and more consistent with the subjective sense of hearing. That is to say, with the development of science and technology, we will be able to express the psychological feelings of subjective listening with the description of objective physical characteristics.
One, T/S parameter
The T/S parameter is the basic parameter of the mathematical model of loudspeaker system first proposed by THIELE and SMALL. The guiding role of T/S parameters in the design of the loudspeaker system has been widely accepted by the manufacturers and engineers, and is supported by almost all the common acoustic testing systems and the design software of the loudspeaker system. The T/S parameters are composed of small signal parameters and large signal parameters.
The small signal parameters include four basic parameters:
Fs is the resonant frequency of the loudspeaker unit.
Vas is the equivalent volume of the loudspeaker unit.
Qes is the electrical Q value of the loudspeaker unit.
Qms is the mechanical Q value of the loudspeaker unit.
The large signal parameters include two basic parameters:
Pe (max) is the maximum power rating determined by the heat dissipation capability of the loudspeaker unit.
Vd is the volume pushed by the loudspeaker element at the maximum amplitude.
The above parameters are mainly provided to us to simulate and design the frequency response characteristics of the horn cell near the resonant frequency. By optimizing the structure parameters of the box, the frequency response of the loudspeaker system we expect is expected to meet the different usage and different usage requirements. In a sense, T/S parameters are not better, only more reasonable and more appropriate. For example, the ratio of Fs/Qts is suitable for that kind of sound box system in that area, and how Vas is more reasonable. The most important thing about T/S parameters is how to match and optimize them. It is important to point out that the actual measurement error of T/S parameters should be paid enough attention to. The T/S parameter error is too large, which will cause the theoretical value to deviate too much from the actual value in the process of system design, or even lose the guiding significance of T/S parameters. In practice, the following aspects will cause measurement errors. The error caused by different test methods. For example, the error of constant pressure method and constant current method, the error of volumetric method and loading method. In the loading method, the error caused by the load is selected. According to experience, the constant pressure method is more sensitive to the loading magnitude than the constant current method, and causes greater error.
The error caused by different test levels. The same problem exists in the constant pressure method and the flow fixed method. A measurement of the error caused by a given value in an operation. For example, the "vibration area" and "DC impedance" and other parameters, especially the "vibration area", have great influence on the measurement results. The error caused by other factors. For example, the testing environment, the orientation of the horn unit to be measured, the impedance of the test cable, etc.