Vinyl Records Restoration; How To Get Professional Results - Noise Reduction


by gaston gazabatt - Date: 2009-11-23 - Word Count: 800 Share This!

While in the previous stage it was necessary to be watchful, to leave no click, now we will need our best ear to eliminate the background noise, without affecting the musical program material. As we have noted above, this is a work that is to listen and listen again until we be satisfied with the adjustments. The fully automated filters for removing clicks and background noise always miss some detail or cut excessively high frequencies.

Stage 3: Removing noise.

Now our recording has no clicks, nor pops and exhibit a smoothly background noise with a profile that will be easier to identify and, therefore, to suppress. Adobe Audition 3 includes an excellent noise suppressor that do a great job in most of the cases. But, in my opinion, the best choice is Z-Noise. Z-Noise is a plugin from Waves, which makes a work really precise, with multiple algorithms that remove the noise with minimal side effects.

To reduce the noise we will use the same visual configuration that for the click and pop removing: Frequency Spectrum Display, inverse video mode, main window deploying 15 seconds of playing time. Now seek a region of the file with no music, for example, the silence between two tracks. We can see clearly the noise, especially in the high frequencies, which is noticed as a fuzzy cloud. Select a region of a couple of seconds and activate Z-Noise. The Learn mode allows you to identify the pattern of the noise and then to eliminate it from the musical program without affecting the rest. Capture this pattern of noise and seek now another selection, 15 to 20 seconds, which includes music and silence and where the background noise is clearly audible. Apply Z-Noise, listen carefully and experiment with the adjustment of Threshold and Reduction until the noise disappears. The Difference button allows you to hear only the noise that is being eliminated; if you listen more than noise, is that the noise reduction is affecting the musical material and then it is necessary to reduce the Threshold or the Reduction level. We achieve better results with two passes, with light noise reduction adjustments, rather that a single pass with greater reduction level. Z-Noise includes other adjustments that you may experience for best results. As in the previous stage, apply the filter, in this case Z-Noise, to a featured part of the piece or to an important musical passage and compare, listening carefully, the difference between the processed region and the remaining material with no noise reduction. If you are satisfied with the result, execute "Undo" and then apply the filter to the entire file.

It is possible that at this point you are already satisfied with the final work. But the elimination of the main noise makes appear some tenuous or less noticeable ones as "rumble" and "hum". To eliminate "rumble" an excellent plugin is Ray Gun Pro from Arboretum Systems, which also includes other options for restoration. The "hum" generated by problems of electrical connection is removed effectively with X-Hum from Waves. Finally if you think that, after the noise reduction, the recording has become opaque, which it has lost something in high frequencies, I recommend to use the plugin Ozone 4 from iZotope. Ozone 4 includes a powerful combination of modules as a parametric equalizer, an harmonic exciter to restore or regenerate those lost harmonics due of high-frequency filters or noise reduction, a module to improve the stereo image, etc.

We have already completed the restoration of the LP and it remains a last optional work. One of the major differences between digital music with analog music, recorded on magnetic tape, that is the dynamic range. The 16bit digital music reaches the 95dB, while the analog music to save the problems of tape saturation and background noise, that do not exceed 60dB.This can be corrected, if you wish, with a compressor expander, such as C4 from Waves. To use a compressor is not easy and it will require practice to achieve good results, but it could get back the dramatic quality of the music, increasing the difference of level between the quiet and the strong sounds.

Finally we have to separate the tracks for the CD transfer. I recommend to leave about 3 seconds of silence before the end of each track and 0.2 to 0.3 seconds before the start. With Adobe Audition you can select each piece of music and save the selection as a new file. It is practical if each track is saved with the prefix 01_, 02_, etc, plus the name of the song and thus there be automatically sorted for burning them on CD.

The restoration of an LP is a work that requires dedication if you want to achieve sound comparable to CD quality, but it is certainly gratifying and worth the effort.

Related Tags: noise, click, pop, vinyl record, record restoration, cd format, cd quality, 16 bit, adobe audition, waves bundle

Your Article Search Directory : Find in Articles

© The article above is copyrighted by it's author. You're allowed to distribute this work according to the Creative Commons Attribution-NoDerivs license.
 

Recent articles in this category:



Most viewed articles in this category: