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eyadams · Jul 14, 2007, 11:10 AM

Has anyone else had this happen? Occasionally when I import a song from a CD there is a clicking noise added to the track. The noise can be heard on the computer and on my iPod, but when the original CD is played on a plain CD player it cannot be heard. For me it has happened both on completely new CDs and on older CDs that have scratches but still play.

I'm importing using the default settings (AAC, 128, CD error correction on). I've played with the higher bit rate and error correction on and off. Doesn't seem to make a difference. My Mac is a 1st Gen G5, SP 1.8 Ghz, original CD drive.

ChrisB · Jul 15, 2007, 12:08 PM

What CD is it and how new is it? Some labels have played with anti-copy technology to screw up ripping. Is the clicking happening on a regular basis at a regular time interval?

analogika · Jul 15, 2007, 02:18 PM

In the iTunes preferences, check "use error correction when importing CDs".

Your CD is probably defective.

Dakarʒ · Jul 15, 2007, 02:24 PM

I've had this happen to me as well. I don't see how this is CDs fault, though, if regular CD players handle it fine.

I always have error correction, I've been meaning to try reimporting some of these with it off to see if it changes anything.

analogika · Jul 15, 2007, 03:11 PM

Originally Posted by Dakarʒ

I've had this happen to me as well. I don't see how this is CDs fault, though, if regular CD players handle it fine

Again, despite what voodoo thinks:

The error correction used on audio CDs is a different and less effective kind than what's used on data CDs, because it is *assumed* that CD players will have error correction to interpolate missing data.

This is also the reason why NO burning or mastering application I have come across to date gives the option of verifying burned audio CDs - and none of them do (if you wish to transfer session audio between studios on CD, always burn it as a data CD rather than an audio CD).

Scratched or faulty CDs are more likely to play correctly in an audio CD player because in an audio CD player, a certain percentage of what you're hearing at any given time is error correction-interpolated signal.

On the computer's drive, the bad segment is read several times until it makes sense (which isn't necessarily the actual original signal, apparently), or it is skipped, I'm not sure. Both would be explanations for the clicking.

Unless you turn on error correction, in which case a CD-player-like interpolation is used which simply "makes up" data it couldn't readily decipher.

Dakarʒ · Jul 15, 2007, 03:19 PM

So what you're telling me is, a computer's ability to read an audio cd is inferior to a dedicated cd player?

analogika · Jul 15, 2007, 04:25 PM

Originally Posted by Dakarʒ

So what you're telling me is, a computer's ability to read an audio cd is inferior to a dedicated cd player?

No, it's actually superior, because it can make a second pass at data it couldn't get the first time.

A dedicated CD player will make **** up as it goes along.

Dakarʒ · Jul 16, 2007, 07:12 AM

So why am I not hearing these pops and clicks from the same CD in the 'inferior' audio player?

eyadams · Jul 16, 2007, 10:46 AM

I had this problem a brand new, completely unscratched copy of the Beach Boy's 40th Anniversary release of "Pet Sounds", which is actually an SACD. Most of the tracks play absolutely perfectly, both on computer and on a regular CD player. But I've seen it on other, less exotic discs, and scratches on the disk don't seem to be a factor.

As I noted originally, turning on "CD Error correction" doesn't seem to make a difference. And the popping noise is reproducible - in the case of "Pet Sounds", no combination of settings makes a difference. Furthermore, the popping noises are identical every time the track is imported.

I'm relieved to see that other people are getting it as well. I was worried it was just me.

analogika · Jul 16, 2007, 12:49 PM

Originally Posted by Dakarʒ

So why am I not hearing these pops and clicks from the same CD in the 'inferior' audio player?

Because the "inferior" audio uses always-on interpolative error correction, as in, "it makes **** up as it goes along".

If you've ever had a little experience with "high end" audio stuff you'd find that "high-end" CD players will generally tend to have a HIGHER skip rate and LOWER scratch tolerance than cheaper CD players.
The reason is that cheaper CD players have stronger error correction, which is permanently on to compensate for cheap drive mechanisms. The problem with this is that cheap CD players will *always* make **** up as they go along, meaning that they're a smoother ride, but at a by defiition consistently inferior audio fidelity (since interpolated, i.e. made-up audio signal is less true to the source).

analogika · Jul 16, 2007, 12:54 PM

Originally Posted by eyadams

As I noted originally, turning on "CD Error correction" doesn't seem to make a difference. And the popping noise is reproducible - in the case of "Pet Sounds", no combination of settings makes a difference. Furthermore, the popping noises are identical every time the track is imported.

That seems to point towards some nefarious copy protection mechanism.

Is there a "compact disc digital audio" logo on the disc?

If not, it's not actually an audio CD and can be returned as defective if it was sold to you as an audio CD. That is, if the sales people didn't explicitly note that the disc did not conform to audio CD standards, they basically frauded you into buying something which was not what it appeared to be. But that just as an aside.

Dakarʒ · Jul 16, 2007, 12:58 PM

Originally Posted by analogika

Because the "inferior" audio uses always-on interpolative error correction, as in, "it makes **** up as it goes along".

So basically, there's no way to get iTunes to do this and we're ****ed?

analogika · Jul 16, 2007, 01:00 PM

Originally Posted by Dakarʒ

So basically, there's no way to get iTunes to do this and we're ****ed?

That's EXACTLY what the "use error correction when importing CDs" checkbox does.

Dakarʒ · Jul 16, 2007, 01:02 PM

Ok, thanks. As I said earlier, I wanted to try that because I actually thought it was the cause of my problems. (Way to go me)

shifuimam · Jul 16, 2007, 03:24 PM

Have you tried to use anything besides iTunes to import the CD?

If you have access to a Windows machine, try ripping the music to uncompressed WAVs using CDex and see if you still are getting the popping or clicking noises in the songs. If the audio is clean, you can compress the WAVs to MP3 using CDex, or rip to MP3 directly from the CD (which will handle the ID3 tags for you - I'm pretty sure you lose that data if you just rip to uncompressed WAV).

Dakarʒ · Jul 16, 2007, 03:29 PM

Hmmm... this reminds me, I wonder if I have tried just dragging the AIFF file from the CD to the desktop, then to iTunes.

eyadams · Jul 29, 2007, 11:27 AM

After posting this thread, I heard about a Shareware program called "ClickRepair" that fixes the problem 100%. It is, quite simply, amazing

It's written for people who are digitizing LPs, and is designed to remove some of the noise inherent in that medium. But it works perfectly for this problem as well. The only real drawback is that it doesn't work with m4p files, so I when I want to clean a song or songs I have to dig up the original CD. Not a big hardship, but I haven't been as neat in orgnizing my CDs as perhaps I should have.

Dakarʒ · Aug 3, 2007, 02:56 PM

Originally Posted by analogika

That's EXACTLY what the "use error correction when importing CDs" checkbox does.

Last night I had the presence of mind to turn off the error correction and tried reimporting my most notorious problem tracks (10+ year-old CD, scratched up, the original file was 2 minutes shorter than it should have been in itunes). The track came out audibly flawless. I imported some other tracks that were giving me trouble as well but I haven't gotten around to listening to those too.