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Copyright © 2009 by Wayne Stegall
I read an article promoting a test disk that would improve on a cd player’s sound. Because it sold for about $30, I decided to make my own. Subjectively, I believe my cd player’s treble became smoother. A small amount of listening fatigue that it had previously seemed to have went away entirely even while listening with headphones.
Track 1: (15 mins) white noise
Track 2: (15 mins) sawtooth wave (1kHz)
Track 3: (15 mins) square wave (1kHz)
Track 4: (15 mins) hf white noise (band limited 14.7kHz – 22.05kHz)
Track 5: (14 mins) demagnetization (exponentially decaying 1kHz sine waves)
Download the Audacity wave editor from audacity.sourceforge.net. Also get the first two plug-in packages under plug-in downloads. Install these on your computer as instructed. Because I had Nero 6.6 to use, I only used Audacity to generate the original signals. I used Nero for normalization and filtering. The plug-ins available for Audacity should and seem to allow this functionality as well.
· For the first track, generate 900 seconds (15 mins) of white noise. Normalize the signal to the highest level. Export as wav file.
· For the second track, generate 900 seconds (15 mins) of 1kHz sawtooth. Normalize the signal to the highest level. Export as wav file.
· For the third track, generate 900 seconds (15 mins) of 1kHz squarewave. Normalize the signal to the highest level. Export as wav file.
· For the fourth track, import the first track. Apply highpass filter at about 14.7kHz. Normalize the signal to the highest level. Export as wav file.
· For the fifth track, generate 840 seconds (14 mins) of 1kHz sinewave. In varying lengh sections apply exponential fade-out. Normalize the signal to the highest level. Export as wav file.
Burn the resulting wav files onto a CD-R in the indicated order. Play the disk in your cd player until you get the intended effect. (24 hours on repeat play or equivalent should do.) Track 5 should not be interrupted in the middle if you desire the demagnetization effect; you might finish up on this track. After that just use the disk as needed or desired for maintenance.
· Note: The test signals on this disk were not meant to exercise speakers, use low or zero volume to amplifier.
If you do not want to create your own CD-R from scratch, you can download mine. Download and extract the contents of the zip file into convenient directory. Then use a cd burning program to burn them into the desired test disk. The programs should convert the mp3’s back to pcm during the burning process. I tested this with Nero 6.6; other commercial programs should do the same. In the worst case, you may have to manually convert the mp3 files to wav format before proceeding. Any roughness or distortion of the test signal caused by the conversion from pcm to mp3 and back will not affect the disks usefulness as it is not meant for listening.
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