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How to Remove 2-second "Pre-Gap"?


OutsideTheLaw

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I'm running Dell-installed Roxio Creator Premier 9.0.116 on a brand new Dimension E520 running Vista Home Premium with 4 GB RAM and beaucoup harddrive. My primary use is burning live music in a lossless format with no gaps. I'm having two problems:

 

1. the Audio > Audio CD tab allows me to "Add Music" from my harddrive. But when I add it, the screen is automatically showing a 2-second "Pre-Gap" for Track 1. When I double-click on that track to get the "Edit CD Properties" screen, the Pre-Gap box shows 2 seconds but refuses to light up/ become active to let me reduce this to zero. The effect is that for Disc Two of a two-disc show, Roxio is adding an artificial two-second gap in the middle of the show. (While this might not bother me when I'm listening (since it's the start of the disc) it definitely is bad archiving and trading form -- besides messing up the integrity of a lossless file it also means that anyone I trade with can't recut the tracks, for example moving some to their own new Disc One, since they'll now get a gap in the middle.) So Question 1 -- how do I get rid of this Track 1 two-second gap. I'm already at the DAO setting on the Options > Data screen also.

 

2. Is anyone else having problems with long -- like a minute or two -- lock-ups every time you place a new disc into the tray. It's like it's reading the disc, but how long does it take to read a blank cdr? Didn't take that long in my prior version of Roxio on XP. While its reading it totally locks up Roxio Creator Premier, can't add new songs, prepare the files for the next burn, etc.

 

I paid extra for this. I'm about to delete it and get Toast or Nero or just install my old Roxio on this new computer if Vista will take it. Thanks in advance.

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Do what you will with all that information, assuming you made it this far, but the 2 second pre-gap isn't an issue. :D

Alright... yet another test.

 

I rewrote the same set of files using Music Disc Creator. Extracting with EAC and Disc & Drive Utility extracted files the exact same length as the original files, not 9 and 16 sectors longer. Apparently, the extra data is being added by the Audio Application on the Home menu.

 

Now, the extracted files were identical whether extracted by EAC or Disc and Drive Utility. However, there is a 256 byte offset in the data when compared to the original .WAV file. (An extra 256 bytes is added to the beginning of the track.) Again, I'm suspecting this is a drive issue. I recall seeing this way back when I got my first CD-R drive, around 1996. Some of us were trying to assess the accuracy of the writes and rips. On that drive, an HP4020i, (yes, that's 4X read, 2X write speeds, CD-RW wasn't thought of then) I seem to recall a 512 byte offset.

 

Anyone interested in this information? Either way, here it is.

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Thanks for the quick response Dewey. If I understand you correctly, you are also telling me that the former versions of Roxio were also installing the two-second "pregap" on every disc I burned even though there was no explicit notice of it on the prior version I was using because such a gap is "required" by the standard (not by Roxio)? Please confirm.

 

As to the "why I care" issue: in high level lossless music trading circles it is verboten to mess in any way with the taper's original capture. Knowingly adding a gap violates that rule. And it could matter to the person you're trading with. Assume the discs are split 8 tracks and 8 tracks, with the encore break between the 4th and 5th tracks of D2. My recipient might want to EAC extract [no one would ever use the Windoew or Roxio ripper!] and reburn the discs with the split after the 12th track, with the encores on D2. If Roxio is inserting a "pregap" at the beginning of D2T1, that becomes D1T9 on the recipient's burn, and he then has a gap in the middle of the concert.

 

OTL ("To live outside the law, you must be honest")

 

 

If you go out and look up the Red Book specifications for an Audio CD, the 2 second pregap on the first track is required, so you can't get rid of it. I'm not quite sure why this is such a problem since if you're playing a long track, then starting a new disc, obviously there's going to be a bit of a delay in changing discs. But, the long and short of it is that an Audio CD is required to have the 2 second pregap on the first track. I think most packages simply don't show that it's there, even though it really is.

 

For archival work, you'd actually want to save the .WAV file on a Data CD because then you'd have the ECC correction codes on the disc, just another layer of data protection, which Audio CDs don't have. At that point, there's no "pregap" or it can be edited out. I'll have to check, but I don't think when you extract the first track that the 2 seconds shows up in your extracted file, but I'll have to try it to be sure.

 

As for the lock-ups you're seeing, I don't get that, so I'm not sure what may be causing it.

 

Hope that helps!

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Thanks for the quick response Dewey. If I understand you correctly, you are also telling me that the former versions of Roxio were also installing the two-second "pregap" on every disc I burned even though there was no explicit notice of it on the prior version I was using because such a gap is "required" by the standard (not by Roxio)? Please confirm.

 

As to the "why I care" issue: in high level lossless music trading circles it is verboten to mess in any way with the taper's original capture. Knowingly adding a gap violates that rule. And it could matter to the person you're trading with. Assume the discs are split 8 tracks and 8 tracks, with the encore break between the 4th and 5th tracks of D2. My recipient might want to EAC extract [no one would ever use the Windoew or Roxio ripper!] and reburn the discs with the split after the 12th track, with the encores on D2. If Roxio is inserting a "pregap" at the beginning of D2T1, that becomes D1T9 on the recipient's burn, and he then has a gap in the middle of the concert.

 

OTL ("To live outside the law, you must be honest")

Okay... I'm finally ready to answer your question. Yes, the 2 second pregap is already on every disc you've ever burned. It's even on every pressed, commercial disc you own. To prove it, put one in your drive, open Creator Home, select Tools and Disc Information. On the Disc Information screen is a check-box for "show pre-gaps on Audio CDs". Check that and give it some time. One reason I'd never noticed that before is that I've always use Music Disc Creator to write my Audio CDs. Just a preference, I won't suggest that it's better or worse than writing from the Creator Home, Audio option.

 

Now, when you extract the first track of an Audio CD, that pre-gap does not come with the track. Using the Disc & Device Utility with Roxio to read a track that I just wrote to disc, the first track comes back 9 sectors longer. (Each sector is 1/75th second.) I suspect that's an issue with the utility because it came back that same 9 sectors longer on 3 different drives. The second track came back 16 sectors longer, again, on 3 different drives. I don't have EAC on my system (never had much luck with it, personally) to test Okay... I just downloaded EAC, and it extracted those files the exact same length as Disc & Device Utility from the Roxio Tools.

 

Once again, I'll suggest that while an Audio CD is lossless, it is not as robust as a Data CD with .WAV files on it, which has extra ECC on it. I realize though, that traders don't want to deal with .WAV files, they want to deal with Audio CDs.

 

Okay... let's make it even more interesting. I used EAC to extract the first two tracks from the CD I just wrote, and used each of the my three drives (listed in my signature). All came back with the exact same length, EAC reported no errors from any of the drives or tracks. But, comparing the files, they're all different from drive to drive, but when I compare the extractions between EAC and Disc & Drive Utility for the same drive, the files are identical. So, I'm going to suggest that you have no guarantees of bit-for-bit accuracy when trading Audio CDs, even when using EAC.

 

One more bit... sorry, just never satisfied. I opened two files extracted using different drives in a Hex editor, and stripped out what appeared to be an offset of zero data at the front and end of the tracks (including silence at the end of the tracks. That made them an identical length. Comparing them, they were identical. Now, comparing one of those Hex-edited files with the original .WAV file, there were a couple bytes different in the RIFF header, but that would be because I didn't correct for the shortened length of the edited files, otherwise, they were identical.

 

Do what you will with all that information, assuming you made it this far, but the 2 second pre-gap isn't an issue. :D

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Yes, I know that this thread is already a month old and no one else has replied but I was directed here from a reply in my thread: [DAO (Disk At Once) Doesn't work on my EMC9].

 

I just thought I would share with you what I learned on the Adobe Audition Forum while trying to figure out why the burned disk was longer than the original *.WAV files.

 

what they told me there was that I had to be using, in the Wave editor in this case "Adobe Audition"

the timescale: "CD 75FPS" and set the "Snapping" to "Snap to Frames" and that no other scale would work and no other snapping type would work either because when the CD burning program whatever was being used in this case ECDC 5 and EMC LE (DELL) would add the files to the CD if there was say 60.16 frames at the end of the Track file it would add the remaining 0.84 portion of the frame to get an exact frame. so this would occur for each track that didn't end in and exact "CD Frame count"

 

Cheers

◄RfD►

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I'm running Dell-installed Roxio Creator Premier 9.0.116 on a brand new Dimension E520 running Vista Home Premium with 4 GB RAM and beaucoup harddrive. My primary use is burning live music in a lossless format with no gaps. I'm having two problems:

 

1. the Audio > Audio CD tab allows me to "Add Music" from my harddrive. But when I add it, the screen is automatically showing a 2-second "Pre-Gap" for Track 1. When I double-click on that track to get the "Edit CD Properties" screen, the Pre-Gap box shows 2 seconds but refuses to light up/ become active to let me reduce this to zero. The effect is that for Disc Two of a two-disc show, Roxio is adding an artificial two-second gap in the middle of the show. (While this might not bother me when I'm listening (since it's the start of the disc) it definitely is bad archiving and trading form -- besides messing up the integrity of a lossless file it also means that anyone I trade with can't recut the tracks, for example moving some to their own new Disc One, since they'll now get a gap in the middle.) So Question 1 -- how do I get rid of this Track 1 two-second gap. I'm already at the DAO setting on the Options > Data screen also.

 

2. Is anyone else having problems with long -- like a minute or two -- lock-ups every time you place a new disc into the tray. It's like it's reading the disc, but how long does it take to read a blank cdr? Didn't take that long in my prior version of Roxio on XP. While its reading it totally locks up Roxio Creator Premier, can't add new songs, prepare the files for the next burn, etc.

 

I paid extra for this. I'm about to delete it and get Toast or Nero or just install my old Roxio on this new computer if Vista will take it. Thanks in advance.

If you go out and look up the Red Book specifications for an Audio CD, the 2 second pregap on the first track is required, so you can't get rid of it. I'm not quite sure why this is such a problem since if you're playing a long track, then starting a new disc, obviously there's going to be a bit of a delay in changing discs. But, the long and short of it is that an Audio CD is required to have the 2 second pregap on the first track. I think most packages simply don't show that it's there, even though it really is.

 

For archival work, you'd actually want to save the .WAV file on a Data CD because then you'd have the ECC correction codes on the disc, just another layer of data protection, which Audio CDs don't have. At that point, there's no "pregap" or it can be edited out. I'll have to check, but I don't think when you extract the first track that the 2 seconds shows up in your extracted file, but I'll have to try it to be sure.

 

As for the lock-ups you're seeing, I don't get that, so I'm not sure what may be causing it.

 

Hope that helps!

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Yes, I know that this thread is already a month old and no one else has replied but I was directed here from a reply in my thread: [DAO (Disk At Once) Doesn't work on my EMC9].

 

I just thought I would share with you what I learned on the Adobe Audition Forum while trying to figure out why the burned disk was longer than the original *.WAV files.

 

what they told me there was that I had to be using, in the Wave editor in this case "Adobe Audition"

the timescale: "CD 75FPS" and set the "Snapping" to "Snap to Frames" and that no other scale would work and no other snapping type would work either because when the CD burning program whatever was being used in this case ECDC 5 and EMC LE (DELL) would add the files to the CD if there was say 60.16 frames at the end of the Track file it would add the remaining 0.84 portion of the frame to get an exact frame. so this would occur for each track that didn't end in and exact "CD Frame count"

 

Cheers

◄RfD►

Ah... yes, that's true. I'm not familiar with Adobe Audition, and assumed what you were doing was supposed to snap to the proper frame. I use CDWave for splitting out my tracks, which will only split on a frame boundary. So, it sounds like you're not getting a 2-second TAO gap in your tracks, but a partial frame "dropout" between your tracks? Much a different thing. In which case, the answer is here, as you've found. Each track must start on a new frame.

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