Audacity Forum

Audacity v 1.3.12 beta
Windows Vista Ultimate SP2

Problem: Click Removal

Attached is a .wav file fragment that I've been practicing with. I'm trying to remove the obvious "click" in the recording. I can't seem to get the "Click Removal" tool to recognize or remove the clicks even with changing the sensitivity settings.

What am I doing wrong?

I've searched this great forum to find many folks suggesting another piece of software (Click Removal) to solve the problem. However, I would have expected Audacity's tool to do it. Am I expecting too much? I have zoomed in on the offending clicks and removed them individually using the "Noise Removal" tool, but this may become impractical in some future recordings.

Thanks for any advice.

Regards, Pat

Yes Audacity's tool should do it ok - but IMHO ClickRepair is a much more effective tool.

Since you are using 1.3 Audacity you could also try the Repair effect. This will fix up to 128 sound samples by interpolating from the neighbouring waveform. You would need to identify where the click is by listening and by looking at the waveform and you will need to zoom in a lot.

WC

Thanks WC:

I can't see that my file attachment is there. Can you access it?

You say that Audacity should do it, but I can't get it to work.

Regards, Pat

No Pat, I can't see any attachment either.

<<<You say that Audacity should do it, but I can't get it to work.>>>
You are selecting the sections of Audio for Audacity to work on before trying to use the Click Removal effect, right?

WC

Yes, WC, I select a portion of the track that has the clicks. BTW, I tried the "Repair" tool and it's works great. Thanks for the tip.

I'm also going to try to upload the .wav file (under 1MB).

Regards, Pat

That's one hell of a noisy sample! Not only some very big clicks (I couldn't even get ClickRepair to fix those) but also a lot of crackle and surface noise.

Do you clean your records befor capturing them?

WC

I just used the "repair" effect to go after those 4 big spikes in the upper wave form. I have never used Audacity's "click removal" effect. It might work as well--I don't know.

Attached are 2 attempts.

I attacked the 4 tall spikes in the upper wave form.

Took about 3 minutes to do both versions.

On Anita-Samplerepaired, you will hear 2 slight thuds where each repair took place.

On Anita-Sampleclicksdeletednotrepaired, you hear 1 thud. Instead of repairing the clicks, I simply highlighted the clicks and deleted them entirely.

You can decide which is preferable.

I've found that if a bad passage is no more than 1/100 of a second in length, it is often preferable to delete it completely, rather than attempt to repair it. You probably won't be aware of the deletion on playback.

The deletion method is particularly useful on passages that are distorted for some unknown reason, but don't actually have a click.

This was just a quick attempt. You might be able to do a thud-free repair if you took more time.

Here is a third attempt.

This was using Brian Davies ClickRepair tool with Wax Cylinder's default settings.

Note that this leaves a couple of thuds also.

Pat,

when I started out doing click removal a few years ago I was using manual methods with Audacty: and I used to use the deletion method you describe - and you're right that in most cases you won't notice the deletion. In fact I will still do this for a very damaged recording (like the sample you provided). But what I do to improve the "join" where both ends of the deletion meet is to select some samples either side of the join and then use Effect>Repair to smooth the join as sometimes you can get a small click if the audio does not match up across the join. You can help to avoid this by either using Audacity to search for zero-crossing points around the damaged part of the Audio - Audacity can adjust its selection to cut at such zer-crossings both sides of the selection. Or you can visually examine the waveforms either side of the damaged part and judge by eye where the waveforms are likely to line up best after the deletion is made.

Another regular poster on the forum, Stevethe fiddle, has in the past suggested another method wherby you silence the damaged part (make the selection and use the Ctrl+L k/b shortcut). Then find a similar matching neihbouring sound sample of the correct leght from nearby to copy and post over the silence (or position it appropriately on the timeline in a new track under your recorded track).


As ignatz pointed out, using CR with "my" default settings still leaves two noticeable thumps - and indeed using it with the settings cranked up much more aggressively still leaves noticeable thumps less, so but still noticeable - but this then removes more of the "music" signal from your sample.

Which brings me back to my earlier question: this sounds like a record with a large lump of crud on it rather than one with a scratch. Have you examined this record with a magnifying glass, is it crud - and if so can you gently clean it off?

WC

Thanks ignatz and WC for your efforts. Again, the Audacity "Repair" tool did a wonderful job and will probably be acceptable for all practical purposes. I guess I expected too much from the "Click Removal" tool. This is a learning process for me and I'm not expecting "professional" or "commercial" quality output. Just the best I can achieve, to save my aging collection.

As has been mentioned, once the file has been created, the real time comes in editing and cleaning up. It will always be a tradeoff between time to edit and quality of reproduction. I'm getting a little deaf in my old age, so I may not notice some of the small stuff when I play a CD on my 40 year old (but great) sound system.

The attachment (Anita Sample.wav) is from a cassette tape (30 years old) and not a recording I made. The tape was bought in Panama. Actually, the click is about 20 seconds long and sounds just like a bad scratch in an LP, because the click grows in loudness as the tape proceeds. There is no information about the artist only a stamp from the store where purchased. Obviously, a bootleg copy.

At this point, I am digitizing commercially produced cassette tapes that I've have for more than 30 years, and would like to save. I have about 75 of these. I'll then move on to my LPs (about300). The LPs are in very good condition, but there are scratches, and some scratches are bad. On the other hand, I'd hate to spend the money it would take to replace my collection with digital media.

The Audacity software is just great and this forum is invaluable for us beginners. Thanks so much.

Regards, Pat