How to consider the impact of audio analog signals after being transmitted through a 100m long cable?

在学习的路上

How to consider the impact of audio analog signals after being transmitted through a 100m long cable? [Copy link]

How to consider the impact of audio analog signals after being transmitted through a 100m long cable? Has anyone seen similar theoretical analysis? Please recommend

maychang

For audio signals, the upper frequency limit is only a few kHz, so there is no need to consider the impact of a 100m long wire. At most, the voltage drop on the wire resistance should be considered. If the signal amplitude is very small, the impact of stray noise signals in the environment on the transmitted signal should be considered.

cruelfox

There is a special audio analyzer. Connect the line between the output and input of the instrument to measure.

chunyang

The frequency of audio signals is not high, and 100 meters is not a "long line" for audio signals. You can calculate the wavelength of the audio signal yourself. As maychang said on the second floor, at most you only need to consider resistive attenuation and interference coupling.

在学习的路上

maychang published on 2020-12-8 12:23 For audio signals, the upper frequency limit is only a few kHz. There is no need to consider the impact of a 100m long wire. At most, the voltage drop on the wire resistance can be considered. If the signal amplitude is very small, ...

Is there any theoretical analysis process that can be recommended?

How to eliminate the influence of stray noise signals on the transmitted signal? Should the transmission cable be shielded? How to deal with it at the acquisition end?

在学习的路上

chunyang posted on 2020-12-8 14:39 The frequency of the audio signal is not high, and 100 meters is not a "long line" for the audio signal. Calculate the wavelength of the audio signal yourself. For example, the second floor...

How should I consider this specifically? Does anyone have any specific recommendations or guidance? Thank you!

chunyang

Published on 2020-12-8 18:37 How should I consider it specifically? Does the master have any specific recommendations and guidance? Thank you!

That depends on what you want to do. As for the question in your main post, the second post has already explained it very thoroughly. The so-called "theoretical analysis" is at most Ohm's law. But the problem is that this is not what you want. In other words, the question in the post is not the problem you want to solve.

To get quick and effective help, first describe your problem correctly and completely.

chunyang

Published on 2020-12-8 18:32 Is there any theoretical analysis process recommended for this? How to eliminate the influence of stray noise signals on the transmitted signal? Use shielded wire for transmission cable? Use...

Dealing with noise has nothing to do with "theoretical analysis" but with taking appropriate measures, such as differential transmission, current transmission, and the use of shielded wires, which have been used for a hundred years. A hundred years ago, the audio signal of telephones and cable broadcasting could be transmitted for more than a hundred meters, and even the MIC line was often tens or hundreds of meters on the stage.