sounds → Sounds are recorded by diverse devices › Spectral characteristic of sound data: Dependent on codecs, devices, environments,,, › Difficult to handle it as training data e.g. Differences by codec Airport - London 0 1 5 2 3 4 Frequency [kHz] 10 5 0 MJOFBS 1$. Airport - London 0 1 5 2 3 4 Frequency [kHz] 10 5 0 0 1 5 2 3 4 Time [sec] Frequency [kHz] 10 5 0 MJOFBS 1$. PHH 7PSCJT