Digital Distortion - What is this popping - echo sound I'm hearing?

[hdomke]

I'm in the process of ripping all my CDs to my hard drive. I'm doing this in iTunes and I'm saving them in the Apple Lossless format. I am turing on Error Correction when I am doing the importing.

 

Occasionally (about 1 in 500 songs?) I am hearing obvious distortion. It is sort of a soft click-echo laid on top of the music. It will drift in-and-out on one song. Then the rest of the songs on that album are fine.

 

This is not due to my wireless network, because I hear the exact same distortion in the same place when using a wired setup.

This is not on the original CD.

 

What is this type of distortion called?

Where does it come from?

How do I prevent it?

Why isn't the "Error Correction" keeping this from happening?

 

Thanks for your help!

Henry

 

 

 

 

[Innertuber]

Hi Henry

 

Not my expertise, but I've at least heard of this, but not the real solution. Some of the things I've seen are iTunes version related when upgrading. Driver related. Some seem to say they reinstalled iTunes. Wish I could help more. Hang in there tho - others here much smarter than me. I'm more the color commentator I think.

 

[The Computer Audiophile]

Hey Henry - This really concerns me. It would really stink to rip a couple thousand CDs only to find out scattered songs didn't rip perfectly.

 

Is there any way you can make a copy of a "bad" song available for us? I'd love to post it up on the site so everyone can have a listen.

 

What if you re-rip the "bad" song, does the same distortion appear?

 

When you are ripping the music is your computer doing other things?

 

I'm just trying to eliminate some things. I'm also contacting some other sources to see if they have solved this in the past.

 

[markr]

I think I do know the sound you describe, but it was on someone else's source material. If this is the same type distortion and I remember the situation correctly, the optical drive that the recording originated on eventually turned out to be bad.

 

markr

 

[hdomke]

Chris,

I would love to post a song that lets you hear it, but it is huge (13 MB) and I don't know how to post it. Could I email it to you so you can post it?

 

I did rip the song again. and it was still there.

 

On close inspection of the surface of the CD I can see marks (ink?) that might be the source of trouble.

 

You asked if I am doing other things on my computer when I am ripping music.

Yes, I am always doing several things at once.

 

Thanks,

Henry

 

[The Computer Audiophile]

If you can email me I'll post it pretty quick.

 

[hdomke]

Chris,

Sorry about the delay.

Could you email me your email address so I could send this to you?

 

Thanks,

Henry

 

 

 

[The Computer Audiophile]

eMail sent!

 

[The Computer Audiophile]

Hey guys here is the file. Please be respectful of the artist's copyright on the song.

 

Click to download.

 

[markr]

I'm not sure what you would call this sort of distortion Henry. I haven't run in to this one before. It is almost like a vinyl "pop" to my ear. Visually, at the point of the "pop" the waveform looks like what should have been an almost instantaneous point in time was artificially stretched to 3 or 4 milliseconds in length. I'm pretty sure that this is due to the surface imperfection that you reported in a post subsequent to your first post of this thread. Check the discs for the other pieces of music that you report having the same issue. I'm betting that you will find visible imperfetions.

 

You gotta love Ry Cooder by the way!

 

markr

(Artist copyright now restored - intact - by me)