Шум. Как уменьшить шумы аудио и радиоаппаратуры? Зачем попу преамп?

Noise in amplifiers, preamps and other radio equipment has reached very low levels with modern technological development and we have already stopped noticing it. But noise has not disappeared. It is there, and any knowledgeable engineer pays special attention to it. The fight against noise is still going on. Even audiophiles do not forget about the noise of their audio equipment. But what do we know about it? Is it possible to make it smaller if you are not satisfied with it. How to reduce noise? Contents 00:00 Noise is always there 0:46 Imperfection of phonogram carriers 1:35 What is the difference between audio equipment and radio equipment 2:17 From zero to infinity 2:26 Is it possible to get rid of noise? 3:25 Noise Classification 4:22 Additive and Multiplicative Noise 5:23 Correlation Function and Spectral Density 5:50 Effective Noise Value 6:00 Spectral Density Units 6:44 Thermal Noise 6:55 Nyquist Formula 7:25 Free Energy! 8:06 Nyquist formula for quantum physics 8:59 Shot noise 10:15 Schottky formula 11:23 Generation-recombination noise - GRN 12:33 Avalanche noise 13:26 Flicker noise 14:38 Quantization noise and dithering 15:17 Oversampling and increased bit depth 15:45 Noise shaping 16:40 Friis formula for a multi-stage amplifier 17:40 What is noise figure (noise factor)? 18:43 Power matching 18:57 Practical consequences of the Friis formula 19:25 Examples of noise reduction 20:03 Using preamplifiers 21:08 Experiment. Microphone preamp noise 23:10 Analysis of noise measurement data 27:06 The facts are there 27:27 Let's go! Support the channel on Patreon -   / ensemb   or Click the SPONSOR button under the video. #Noise #radio engineering