removing scratches from old vynal recordings

All I want to do is eliminate or reduce the scratches and pops that are recorded from older records. Is this possible and easy to do. I can not find the info in the manual???

See here .


The best tool I’ve found for the job is Brian Davies’ excellent ClickRepair - it costs a littke (US$45) but the results are just a little shy of magical. I used Audacity to record the LP, export a WAV too CR and process it and then bring it back into Audacity for all further processing. See this sticky thread:


Yes, I dropped my own two-years old win32 C++ project to automatically remove clicks and cracks from my old vinyls after finding Brian Davies’ ClickRepair.
In the last 2 years I tried numerous methods for automatic crack detection, in the time- as well as in the freq. domain (FFT), but couldn’t find one without false detections. By age (70+) and history my knowledge is restricted to Fourier. Wavelets became usable after about 1996 and mr. Brian Davies as a retired math professor is almost professionally ‘obliged’ to understand the wavelets theory. So he is by far the expert to apply wavelets, with which audiofiles can be splitted into distinct byte streams, each having different frequency content, as were they splitted with a fillet knife and with a dazzling speed.
At first sight I was as impressed as many others by his program until I applied it to a 1955 mono recording of Jacques Douai. After applying Brian Davies’ ClickRepair I heared a sort third-harmonic type of distorsion in the plain voice sections, as if Douai was gurgling while singing. Changing to lighter settings the cracks refused to disappear.
In the wave-form the human eye can find those cracks easily and immediately knowns how the waveform should look like without a crack. It is only so tedious to work that way!
I am still convinced that it must be possible to write software that automatically does what my eyes can do: detect and draw-repair those cracks without introducing new impairments.
I think Audacity is a excellent startpoint for my further experiments and I am very grateful to all the people who contributed to the Audacity project, not to forget the writer of Compiling Audacity® on Microsoft Windows™, who enabled me from yesterday on, to debug-step through the source code.
And if this is not the right place to express my gratitude, would somebody tell me where else?

it must be possible to write software that automatically does what my eyes can do: detect and draw-repair those cracks without introducing new impairments.

I assume you found Effect > Repair (limited to 128 samples).

What Audacity lacks at the moment is high quality click detection (and of course a way to apply Repair at once to all detected clicks).


Yes, I found and used Repair: excellent! And missed the automation of it: pitty.
I used the same method myself, but also on longer clicks. Although with excellent results if used in moderation, I thought to hear a sort of low level plop-impairment when applied with higher concentrations or on longer clicks.

What do you mean by “higher concentrations”? Repairs made “too close together”? Did you possibly include a previously repaired selection in a new selection you were repairing?

Someone did make a version of Repair a while ago that tried to automatically repair regions that were detected clipped above full scale by Analyze > Find Clipping. That might be an approach if we had better (non-clipped) click detection.

Has anyone written any Nyquist plug-ins that look for “small clicks” typical of vinyl records?


Can’t say that i’ve a ready-made Nyquist plug-in kicking about.
There’s a plug that should remove clicks within silent parts. Due to lack of feed back it wasn’t developed further. It has a nice preview function though.
Vinyl scratches are of course another thing. Maybe the detection should also take the RPM in account. If in a first step these regular distanced crackles were labeled, one would be freed from a lot of labour.

That is probably inevitable. In the case of longer clicks the “true” audio is missing - replaced with “click” noise. There is no way that an effect can accurately guess what audio should have been there. Most click repair algorithms guess at the correct waveform by either extrapolating the waveform from before/after the effect, or by simply reducing the level of the click. Either way the “true” waveform will not be accurately reproduced and most algorithms tend to reduce the high frequency content of the repaired section, causing the “plop” effect.

I agree, but as you no doubt discovered from your own programming efforts, it is extraordinarily difficult to accurately distinguish the difference between clicks caused by scratches and clicks that are pert of the music.

For really badly damaged sections, the EZ-Patch plug-in can be useful: EZ-Patch
There is also the PopMute effect New plug-in effect - PopMute (for a description of what this does and how it works you will need to read the topic).