before-silence.wav is recorded with 48k and stereo channels, without speaking and without denoise before-speak.wav is recorded with 48k and stereo channels, with speaking inside and without denoise after-silence.wav is recorded with 48k and stereo channels, without speaking and with denoise after-speak.wav is recorded with 48k and stereo channels, with speaking inside and with denoise before-speak-8k-mono-for-snr.wav is recorded with 8k and mono channel, with speaking inside and without denoise (for computing SNR) after-speak-8k-mono-for-snr.wav is recorded with 8k and mono channel, with speaking inside and with denoise (for computing SNR)