![]() ![]() It tells you how far you are away from destroying the signal regardless of the actual voltage/power figures on input and output and lets you easily calculate gain/attenuation like "my signal peaks at -3dB, I still can make it 3dB louder if need be". In audio electronics, doing the same would have been quite impractical, there is no "absolutely quiet" in analog circuitry and you want to utilize the entire headroom of the signal chain and keep the signal as far above the noise as possible, so the reference level is the maximum level your device can digest without malforming it. ![]() Sound pressure level is measured in "positive dB" because the reference level 0dB is "absolutely quiet" for practical reasons (there is no "loudest noise ever" you could use as reference). I'm not really sure why the digital scale has to be negative, but that it how it is and there is no option to use another scale. So you want to have your analogue levels around this level while your recording so that you get the best sound out of your gear. This 0dbvu usually translates to around -18dbfs, but different converter designs can be calibrated to different levels. However unlike digital, it's alright if your signal goes over 0dbvu a bit because the distortion is usually gradual, and sometimes kind of nice sounding. At this point analoge gear is designed to have its sweetspot, where the signal is high above the noise of the circuit, but not so high that it starts to distort. This level is the zero of the analogue world, 0db vu. So you want to avoid hitting it so that your audio doesn't distort, and you need to keep at least 10db of a buffer away from it so that a sudden loud part doesn't ruin your recording.Īlso, though, the analog stages that your signal goes through, such as your preamps and the analog parts of your a/d converter are optimized to work at a certain level. This happens because digital audio describes the current position of a signal with numbers, and when you get up to 0 the numbers have run out, it's as high as you can go, so the same max number just keeps repeating and the peak of your waveform gets chopped clean off, which creates the sound of distortion. With digital audio, once a signal gets up to 0db it can't go past it, and the signal distorts. Fs means full scale (not sure why but there you go). ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |