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View Full Version : Track transition problems - I feel foolish...


razorboy
2005-03-03, 11:24 PM
Please be patient with my absloute stupidity on this...I humbly ask for your help on...

I have been having a problem with ticks appearing during track transitions with a couple downloads recently. I have a new Dell PC, about 2 weeks old. The problem was happening with my old crusty PC too, but I assumed it was just a combination of an old burner and bad burning software (Musicmatch Jukebox - yikes).

My first downloads with the new PC seemed to be fine - no rough transitions. That was the case for about 20-30 burns, but now I've had a couple with a few minor bad transitions over the last couple days, but one was from EZT, so I assumed that maybe it was an extraction error or something. I also didn't like the fact that the Sonic burning software that I was using that came installed on my new machine was burning everything at high speeds, and you can't adjust that without upgrading...anyway, I completed these 2 torrents yesterday/today:

http://www.thetradersden.org/forums/showthread.php?t=4343
http://www.thetradersden.org/forums/showthread.php?t=4375

I have no doubts that they were perfectly extracted and posted - no one else had any problems (that I know of), but I had rough transitions between about half the tracks on each disc of each torrent. I DL'ed one of them twice just to make sure, and burned some discs 3 times at different speeds and settings with the same results. I close every other thing running on the PC when I burn...I never have more than one torrent on the hard drive at once...I use TDK discs...

I thought it might be a Sonic problem, so I installed Roxio Easy CD/DVD 6 Basic, and tried them with that too, with the same result. In the FAQ, it stated that turning off burner underrun correction would eliminate diginoise and clicks between tracks, but it made no difference. I tried it at speeds from 8x-48x with no difference. My final attempt with Roxio was at 8x, buffer underrun off, and write to hard disc first. I'm just grasping at straws at this point. The discs all had the same bad transitions in the same places, regardless of software, speed, etc.

That made me think that maybe it was a decoding error - one of the torrents was FLAC, one .shn. I've noticed reading other posts that MKW is no longer the preferred .shn tool, but I still use it. Either way, the FLAC files were just as bad. I have only a basic working knowledge of these applications, in other words, I've only used them to decode in the most basic sense. It doesn't seem like there are things I could simply miss or change to fix the problem, but I'd be happy if that were the case.

I hope someone out there can assist here...like I said, I hope it's just something simple that will make me feel like a moron. Thanks for any guidance you can offer.

John

diggrd
2005-03-04, 12:45 AM
What you describe sounds like it could be SBE's. But also it could be something else the way you describe rough transitions and diginoise not justclicks. Since neither torrent post included a shntool report I would run shntool on the flac and shns, stop using MKW and Roxio please. Get Nero.
This new program looks promising http://www.thetradersden.org/forums/showthread.php?t=3904
For more info on Sector Boundary Errors look here
http://www.mrichter.com/cdr/primer/blocks.htm

From http://wiki.etree.org/index.php?action=history&page=SeedingGuidelines
:Tracking at Sector Boundaries
Paying attention to a simple technical issue during tracking can make a noticeable difference in seed quality. Each track of a standard audio CD is composed of "sectors" or "frames" that are each 1/75 second long (also expressed as 2352 bytes or 588 samples long). If a track is properly cut on a multiple of 1/75 second, it is "sector aligned", or cut "along sector boundaries." When it is not properly cut, the last sector is like a ragged end, which CD burning software just fills in with silence. Listeners will hear a click or pop between tracks because of the music -> sub-second silence -> music transition. This is extremely annoying and easily avoidable. Here are some sector boundary tips:

*An easy way of checking for sector boundary errors is by use of [shntool]'s (http://shnutils.freeshell.org/shntool/)len function. If you see a -b- flag next to the listing, that indicates a boundary error. For more discussion of how to detect and repair SBEs and seek tables using shntool and shorten (with command lines or batch files), see [this etree forums thread]. (http://forums.etree.org/viewtopic.php?p=5072)

feralicious
2005-03-04, 03:53 AM
I thought flacs didn't have SBEs. Should I check my flacs as well as my shns?

Also, for burning audio EAC is the way to go. Takes a while to set it up correctly, but once it's going it's very nice. And it's free.
Program:
http://www.exactaudiocopy.de/
Tutorials:
http://users.pandora.be/satcp/cd2mp3-en.htm
http://users.pandora.be/satcp/tutorials.htm

Five
2005-03-04, 04:26 AM
Not only SHNs need to be checked, all formats need to be checked including FLAC and APE.

You can easily check by using foobar2000 (follow the link in my sig for converting shows and scroll down to ssamadhi97's post), Trader's Little Helper (http://thor.prohosting.com/roh0205/), Batchenc (http://www.thetradersden.org/forums/showthread.php?t=3859) or plain old shntool linked above.

for shntool:
shntool len *.flac > len.txt

for batchenc:
shntool len <allfiles> > len.txt

if there are tracks with sector boundary errors -b- will show up the the cdr column. tracks that are fine will display ---

razorboy
2005-03-04, 09:49 AM
thanks for all the ideas - i've installed traders little helper, and i've got nero on the way...hopefully those things will help.

my guy still tells me these have been burning errors, but i can't figure why. no one else came up with SBE's on that floyd buffalo '73 torrent that i had trouble with. i don't get it.

uhclem
2005-03-04, 12:25 PM
I thought flacs didn't have SBEs. Should I check my flacs as well as my shns?

SBE's are internal to the original wave files and have nothing to do with what lossless format they are compressed to. In other words, FLACs and APEs can also have SBEs. The difference is that FLAC has a built-in function to eliminate SBEs during encoding and it arrived on the scene at a point where most seeders had learned about the SBE issue. So you will find a lot fewer FLAC tracks with SBEs on them than SHN. But you should ALWAYS check them with shntool if you care.

my guy still tells me these have been burning errors, but i can't figure why. no one else came up with SBE's on that floyd buffalo '73 torrent that i had trouble with. i don't get it.
I seem to recall discussing this issue with RainDawg and others at STG. I think the conclusion was that even if there are no SBE's you can end up with pops on a disc b/c of buffer underruns, even where the disc burns fine with no reported errors. I speculated that the reason was that when buffer underrun protection is activated the laser stops burning and waits for the buffer to fill. It then begins burning where it left off, but because it is burning an audio disc, it probably recommences burning at the beginning of a sector. No music is lost, but a sector boundary error is produced because odds are the laser left off writing somewhere in the middle of the previous sector.

Anyway, to make a long story short, many have observed that these pops can be produced by burning discs at too high a speed with buffer underrun protection enabled. You should only use buffer underrun protection for data discs.

Hopefully a knowledgeable person could explain to us whether my speculation as to the actual cause of the pops is correct.

One finally possibility is that the disc from which the tracks were ripped already contained SBEs. When a disc with SBEs is ripped the SBEs remain as gaps inside the wave file even though the ripped file is cut along a sector boundary.

razorboy
2005-03-04, 12:44 PM
i would have thought that someone who downloaded the two floyd torrents that i mentioned in my initial post would have mentioned if there were SBE or if the discs burned with transition clicks. no one did, and people that are known to take quality very seriously (like Martin66) ;) downloaded the shows. i'm certain someone would have mentioned it if the errors existed on the source material.

either this happens a lot, and people just live with it (it is free music, after all), or this is a ME problem - i suspect the latter.

as far as speed and buffer underrun, i burned these torrents at as slow as 8x and as high as 48x, with and without buffer underrun on Roxio 6. What is considered acceptable burn speed for stuff like this? I thought 8x and under, but what do the majority of you folks who don't have track transition errors burn at?

are there settings on Nero 6 that prevent this stuff? if it's a software or setting thing, that would be a great relief. i have a hard time believing it could be a hardware problem, as my machine is only 2 weeks old. i have burned A LOT of CDs since it arrived, but come on...

Five
2005-03-04, 12:53 PM
well put.

so the first thing to do is a length check ... if you're using TLH go to the "Audio File Details" and use len mode.

uhclem
2005-03-04, 12:54 PM
i would have thought that someone who downloaded the two floyd torrents that i mentioned in my initial post would have mentioned if there were SBE or if the discs burned with transition clicks. no one did, and people that are known to take quality very seriously (like Martin66) ;) downloaded the shows. i'm certain someone would have mentioned it if the errors existed on the source material.
The reality today is that there is so much stuff being downloaded that ppl often don't get around to listening to their new stuff for weeks. It's the guy with the new computer downloading his first torrent that is most likely to listen closely to his download right after downloading it ;).

I would post in the torrent's thread about the problem and see if anyone else has noticed it. You might also jog a more experienced person into listening to the tracks today instead of 2 weeks from now.

Btw, do you hear any problems when you listen to the tracks on your computer? That can sometimes tell you whether the tracks were ripped from a disc with pre-existing SBEs.

pmonk
2005-03-04, 01:07 PM
either this happens a lot, and people just live with it (it is free music, after all), or this is a ME problem - i suspect the latter.

I hope not :lol

Certainly the final test is when you burn it to CD-R. 90% of the stuff I download stay in my computer and since I just got Nero I have been burning and backingup a lot. Sometimes sbe's cannot be heard when played on foobar (i.e. the Flying Circus Matrix torrented on R-O last year) but the clicks are loud and clear when burned onto cd-r. Every since Five gave the text to show SBE's on Foobar it is a lot easier to ID them. But at this stage of the game with me finally getting a full handle on shntool and Batchen and Trader's Little Helper everyone should now the first thing they do when the download is complete is check the files!

pmonk
2005-03-04, 01:09 PM
The reality today is that there is so much stuff being downloaded that ppl often don't get around to listening to their new stuff for weeks.

Ain't that the fucking truth :lmao:

razorboy
2005-03-04, 02:14 PM
that's a big 10-4...thanks again for all the information - all of you. something we all deal with, i suppose. it isn't a perfect system, and after all, it is free. i guess i notice this stuff more because i burn immediately in most cases. i'll admit i didn't always listen to everything, and certainly not closely, before burning. i now have winamp w/ the no-gap plugin.

i will be listening to everything before i burn from now on, checking everything with TLH, and i should have nero by next week.

thanks again for the suggestions and assistance.

pmonk
2005-03-04, 02:19 PM
Remember - the whole goal of ID'ing errors (i.e. digital erros, sbe, etc... is prevent it from being further distributed into the trading pool.

FYI - Go with Foobar2000. I orginal started with winamp but once I started using Foobar I never went back.

Plus - you can add code on Foobar that SBE's are ID'ed once you add the files to the playlist!

RainDawg
2005-03-04, 02:19 PM
I'm surprised no one has mentioned this first, but here are the methods I would take to determine what is causing this problem. First of all, my gut tells me that you have tracks with SBEs on them....also, I'd bet no one has reported them because only few people actually listened, listened closely enough to hear them, and actually know to look for something like that. You wouldn't believe the amount of stuff I get with skips between the tracks that people just "didn't notice".

Anyway, do each of these things and let me know what happens:

1. Run a sector boundary check using one of the 4 methods posted by Five above. Let me know if there are sector boundary errors on any of the tracks.

2. Play the original files you downloaded, undecoded and unburned, using foobar2000 and let me know if the files playback smoothly or if the same rough transitions are between the tracks.

3. Decode the original files to wav. Open a track where a rought transition is spotted on a wav editing program and zoom all the way in to the end. Also zoom all the way in on the beginning of the next track. Let me know if there is any silence located near the transition point.

4. Extract the audio from one of the flawed discs using EAC. Do the same exercise a step 3 with these extracted files. This will let us know if something was changed during the burning process or if the problem was there originally.


As a footnote, your question isn't stupid at all. Fact is, you have to be vigilant as a trader to spot these things, and know how to figure out the source. There are many lazy traders, even here on TTD, who will simply miss this and seed stuff anyway. Please let me know if you have trouble with any of the steps listed above. We'll get to the bottom of this before you waste and more blank CDRs....promise.

RainDawg
2005-03-04, 02:21 PM
that's a big 10-4...thanks again for all the information - all of you. something we all deal with, i suppose. it isn't a perfect system, and after all, it is free. i guess i notice this stuff more because i burn immediately in most cases. i'll admit i didn't always listen to everything, and certainly not closely, before burning. i now have winamp w/ the no-gap plugin.

i will be listening to everything before i burn from now on, checking everything with TLH, and i should have nero by next week.

thanks again for the suggestions and assistance.

I'd recommend getting yourself foobar2000. It takes some time to get used to and configure nicely, but it reliably plays back all files gaplessly unless they have silence encoded directly into the file. It's an easy way to quickly check if the source you got was flawed or if it got screwed up during your burn process.

pmonk
2005-03-04, 02:26 PM
Besides ID'in SBE, what else can Foobar check????

RainDawg
2005-03-04, 02:42 PM
I'm not sure what you mean by ID'in.....

foobar can check SBEs, yes, and while I'm thinking about it, checksums (md5 or ffp) are the only thing that foobar is unable to check for right now.

razorboy
2005-03-04, 02:45 PM
OK - raindawg, i'll go through those steps, but it may take some time. i'm going to be gone a lot of the weekend, but i did redownload one of the torrents i had trouble with, so that will be the files that i try everything on.

i'll get foobar as well and let you know what i find out.

thanks again for you help.

pmonk
2005-03-04, 02:47 PM
I'm not sure what you mean by ID'in.....

foobar can check SBEs, yes, and while I'm thinking about it, checksums (md5 or ffp) are the only thing that foobar is unable to check for right now.

Checking for sbe's when the tracks are entered into the playlist (ID'ing them by having the tracks with the sbe show up in red and with the code)


source you got was flawed or if it got screwed up during your burn process

What do you mean by this???

RainDawg
2005-03-04, 02:57 PM
Checking for sbe's when the tracks are entered into the playlist (ID'ing them by having the tracks with the sbe show up in red and with the code)
Yes, that's how I do it. In fact, I just have the track time show up in green if it's SB aligned or red if it isn't. Since I drag all new files into foobar when I get them to put file tags on them, I just do a quick glance to see if there are any red file in lot. The formatting string posted here on TTD had an extra bit at the end where it tells you how many samples out it is (if I recall) but I don't really care about that, just yes or no.


What do you mean by this???
Sometimes you download files that are flawed...they have the silences already at the end. Sometimes you download files that have SBEs. The files will play flawlessly, but once you burn them, the gaps will appear. I draw a distinction between files that arrived on my hard drive already flawed and ones that got flawed while they were burnt.

RainDawg
2005-03-04, 03:01 PM
OK - raindawg, i'll go through those steps, but it may take some time. i'm going to be gone a lot of the weekend, but i did redownload one of the torrents i had trouble with, so that will be the files that i try everything on.

i'll get foobar as well and let you know what i find out.
Yeah, getting used to checking all this stuff the first time can take a while. Once you get used looking at all this stuff, it takes only a few minutes to track down who screwed the files up and how. Then you have to decide if they are worth fixing or not....