Critical band scale: mel scale Based on perceptual studies Scale Log scale when freq Is above Am=150: 2m 1KHZ Linear scale when freq is below 1 KHZ Popular scales are the"Mel (stands for melody or"Bark scales 4 m=2595k0 801+ 700 ()Freq in hzu: Af=7000-6000 Feature extraction v 9 Below1KHz,△f≈△m, linear http://en.wikipedia.org/wiki/melscaleAbove1kHz,Af>am,logscaleCritical band scale: Mel scale • Based on perceptual studies – Log. scale when freq. is above 1KHz – Linear scale when freq. is below 1KHz • Popular scales are the “Mel” (stands for melody) or “Bark” scales       = + 700 2595log1 0 1 f m Feature extraction, v.9a 13 (f) Freq in hz Mel Scale (m) http://en.wikipedia.org/wiki/Mel_scale m=150 f=7000-6000 Below 1KHz, fm, linear Above 1KHz, f>m, log scale