Hello, I have some 10 signals in noisy and nonoise(noisy+good) situations. I just calculated the power of each signal in two cases and then used SNR formula for dB(10log noisy/nonoise). Now, I got noise levels in dB's. Here, i confused that these dB levels are refered to sound dB levels or some other dB's. Because, My teacher told me after seeing the achieved values(20dB, 32dB, 14dB......upto 10 signal values) and he said it was full noisy. I am pointing here that what is these dB values and is there any chart for good and bad noise dB values or any information about this is appriciated.