ffmpeg: create test tone

ffmpeg -f lavfi -i "sine=frequency=997:duration=10:sample_rate=48000" -af "volume=-16dB" -c:a pcm_s24le -ac 2 997Hz.wav

• frequency: 997 Hz
• duration: 10 seconds
• sample rate: 48 kHz
• bit rate: 24 bit
• amplitude: -16 dBFS
• channel: 2