Wednesday, May 16, 2007

NotesAudio

NotesAudio
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Filtering -> Remove Noise from Tape Recording




Filtering -> Remove Noise from Tape Recording
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Using Goldwave Software.

Consider the following files:
SndOrig.wav -> original sound from tape recording with noise
SndNoise.wav -> Sample of white noise from SndOrig.wav
SngGood.wav -> the final improved sound file

1. Open Goldwave software and open the SndOrig.wav file.

2. Copy a section of from SndOrig.wav which is mostly noise (with no music)
and save to SndNoise.wav.

3. Copy the music part that we want from SndOrig.wav to SndGood.wav.
Select (highlight) and copy (Ctrl C) from waveform of SndOrig.wav.
Create a new file (File -> New) at 16bit, mono, 22050Hz (assuming original source is tape recording)
Paste (Ctrl V)

4. Open SndGood.wav and apply lowpass filtering by:
Effect -> Filter -> Lowpass/Highpass
Set initial cutoff freq to 2560Hz
Set to Lowpass
Set to Static
Click OK

5. On the SndGood.wav, increase volume by:
Effect -> Volume -> Change
Increase the volume to over 80% total

6. Open SndNoise.wav and "Select All" and "Copy". The noise wav is now in the clipboard.

7. Open SndGood.wav and reduce noise using the noise profile from clipboard by:
Effect -> Filter -> NoiseReduction
Select "Use Clipboard"
Click OK