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psyde
2005-03-05, 06:54 PM
Hi everyone,

I just read Raindawg's guide on Shntool. I followed the instructions and created a batch file that would test for sector bound errors (don't know much about them) and ran a test which found that my files have these errors. I would like to store these lossless files on DVDs and will eventually burn them as wave files on CD-Rs for personal use. Do I need to correct these errors before burning them on DVDs or CDRs?If so, do I use the fix mode without the arguments to repair the files? Please excuse my lack of knowledge, as I am not too comfortable with Shntool at this time.

Thank in advance,
Psyde

dadgad
2005-03-05, 07:40 PM
The answer is "yes"

the command is:
shntool fix *.file extension(.wav, .flac or .shn)

uhclem
2005-03-05, 11:11 PM
The answer is "yes"

Not quite. You only 'have' to fix them before burning them to an audio CD. If you archive them on DVD in the meantime you don't have to fix them because the sector boundary issue only applies to audio CDs.

But if you fix them before you archive them on DVD they will be fixed and you can pass them on fixed.

A couple of things need to be considered before you decide. Are there SBEs on the last track only? Are the files listed in the etree database? Etc.

I use fix mode with the -s r argument, which tells shntool to round to the nearest sector boundary. The default is to move backwards. It doesn't make a big difference really, but with -s r the files change a bit less in size.

And it's not sufficient just to run shntool over all the files. If the show you have is divided into multiples sets, for instance, you should fix each set of files separately. If you don't, there is a chance that a little snippet of one set will end up at the beginning or end of the other set. The size would be miniscule but it could be audible and in any event is technically an error.

Give us some more info and we could help you decide when and how to fix them.

psyde
2005-03-06, 12:38 PM
Thanks for your reply and offer for additional help Uhclem! My primary concern is learning how to archive the lossless files on DVDs or CDs for future use and trading. I may make a few audio discs here and there so I'll eventually need to correct these errors anyways. Many of the shn files that I currently have are on more than one disc. Based on your post, it sounds like I need to run each disc or set independently through as opposed to just running the whole performance.

I just ran the len command for a performance with 3 discs and found that all the files have a sector bound error under the CD-R column. So in this case, I believe that I would have to run the fix command with your suggested arguments 3 times, once for each disc. Afterwards, I would burn the audio disc using EAC/NERO. Is this correct?

Thanks,
Psyde

I don't know if this is helpful, but I found the shn entry on db.etree.org for the performance in question: here (http://db.etree.org/shninfo_detail.php?shnid=17524)

Five
2005-03-06, 12:54 PM
I just ran the len command for a performance with 3 discs and found that all the files have a sector bound error under the CD-R column. So in this case, I believe that I would have to run the fix command with your suggested arguments 3 times, once for each disc. Afterwards, I would burn the audio disc using EAC/NERO. Is this correct?
This is how I would do it. Make a note in the .txt file that you corrected the SBEs using SHNtool and add this to the lineage. Post here if you're not sure how to notate that properly.

For archiving, just burn a data disc using nero. If you want to burn audio cdrs in addition, I recommend EAC over Nero.

uhclem
2005-03-06, 01:48 PM
I'm not trying to make this more confusing, but it's not as simple as just fixing each disc separately, or fixing the entire show all at once. You should look at it from the perspective of musical sets. By musical sets I mean sets of music as played by the band, and you should look at fixing each set regardless of whether a particular set spreads over more than one disc.

So the first thing you look at is whether the show you have was played as a single set or as multiple sets by the band. You are almost certainly not going to want to fix an entire disc as a disc if there was a set break in the middle of that disc. Instead you will probably want to fix all the files of the first set as a set.

Also load up the last song of a disk and the first song of the next disc together in your computer's audio player and listen to the transition. Is it seamless? If the audio between two discs is actually seemless then that's a good reason to fix those files together because you want to preserve the seamless transition. If you were to fix your files on a per disc basis, you would end up introducing silent padding that will ruin the transition. You won't hear this if you burn the tracks to their respective discs, but the reason that this is undesirable is that you can never tell in the future how someone else might burn the tracks to a disc. CDs are getting longer all the time, and what was a good layout for the old 74 min discs may suck on 80 min discs, and be even more useless if 90 min discs catch on. Don't introduce a problem into your files that you or someone else will regret later when longer discs become the norm.

Confused? Well let's look at the show in question:

Disc 1 63:52.80
01 Intro 05:31.78
02 Bartender 08:10.92
03 When the World Ends 05:27.93
04 Busted Stuff 04:45.04
05 Two Step 09:18.04
06 Everyday 06:20.89
07 Grace Is Gone 06:48.74
08 Grey Street 04:22.85
09 Best of What's Around 06:09.04
10 Tripping Billies 06:56.80

Disc 2 66:25.45
01 The Stone 07:52.88
02 Gravedigger 05:14.02
03 Stay or Leave 05:34.52
04 Warehouse 09:44.97
05 Where Are You Going 05:05.50
06 Tim Solo 07:23.31
07 The Maker 06:21.22
08 Crush 10:02.57
09 Don't Drink the Water 09:06.46

Disc 3 69:21.95
01 Exodus > 03:22:01
02 Cry Freedom 06:39.50
03 Lie In Our Graves 10:52.22
04 Pay For What You Get 05:53.58
05 Tim Solo 07:11.31
06 Jimi Thing > 06:11.40
07 What Will Become Of Me 02:44.12
08 #41 06:43.05
09 Ants Marching 07:59.50
10 Nancies Intro 03:38.18
11 Dancing Nancies 08:07.08

I can't tell from this if there was a set break. Maybe there was a set break at the end of disk 1, maybe not. So load up Tripping Billies and The Stone in your audio player, skip forward to near the very end of Tripping Billies and listen to the transition. If it's seamless, then make a note of that. Do the same with Don't Drink The Water and Exodus. If the transition there is seamless you will want to fix those tracks together. I.e. if both transitions are seamless then fix the whole show together. If there is a fade out/fade in or some other obvious cut between each disc, then fix them per disc. If there is a cut at the end of disc 1, but discs 2 & 3 are seamless, fix disc one separately then fix discs 2 & 3 together. I hope this makes sense.

If you happen to know that there was a set break between, let's say, Gravedigger and Stay Or Leave, and the transition between discs 1 & 2 is seemless, then you would fix disc 1 AND the first two tracks of disc 2 all together.

Also, I do the same thing with encores. If the show has an encore I listen to the transition between the last song before the encore and the encore. If it is seamless then I fix the encore along with the tracks before it. But if it is not seamless, I fix it separately, which sometimes means just padding the end if it needs it and the encore is just one track.

One last thing I would say is it is better to err on the side of fixing the whole show at once than on fixing it it in parts, if you are unsure about what you are doing. If you fix it all at once the worst that can happen is that miniscule portions of one track will end up tacked on to the beginning or ending of an adjacent track. Although this is not technically perfect, it is essentially inaudible and is 'good enough' for most people (although maybe not for trading purposes). Whereas if you fix each disk separately but one or more discs were seamless, that seamlessness will be lost and if the tracks are ever burned to CD in a different layout than that proposed, a pop may well be audible between the tracks that were originally listed on separate discs. That's why you hear people say to fix the whole show at once. But being the anally retentive perfectionist that I am I never just run shntool over the entire show w/o considering set changes and encores.

psyde
2005-03-06, 02:15 PM
Thank you everyone for your comprehensive answers. Uhclem, I will probably have to reread your post again when I try fixing the files, but you were very clear in your explanation and I understood what you mean by "set" now. The examples were very helpful indeed.

Thanks!
Psyde

Five
2005-03-06, 06:17 PM
way to go uhclem you're absolutely right.

RainDawg
2005-03-07, 08:38 AM
uhclem is right, but just to add a simple rule of thumb...you shoud always fix groups of files that run together seamlessly as one cluster, with a fadeout or silence at the end. Therefore the last track will get padded with addtional silence and it won't be audible. On compilation sets where every tracks fades to silence, you really need to pad each track individually.

feralicious
2005-04-14, 06:43 PM
How do you fix an SBE if it's only on the last track? I don't happen to have any silence lying around to use as a dummy last track. Isn't there a command that will just pad the end of it so you don't have to have a second track for the fixing?

Five
2005-04-14, 07:08 PM
yeah, this is the command (courtesy of uhclem):

shntool pad -postpad -o flac [filename]

I haven't tried it yet.

The other way is to decompress to WAV, then recompress the single track to FLAC using FLAC frontend with "align on sector boundaries" enabled, then it will pad the track. Do a shntool len check when you're done to verify that everything is kosher.

feralicious
2005-04-14, 08:41 PM
:thumbsup

feralicious
2005-04-14, 08:52 PM
Aw geez... now in order to make shntool keep it in flac level 8 I have to find that post with that info on it, which now that I think about it I have no idea what level this was encoded at to begin with...

Is there a way to see at what level the flac encoding is was done? I think this came up before, but I have no idea what thread it was in... I'm going bonkers with this stuff. Bonkers I tell ya, BONKERS!!! :crazy:

pmonk
2005-04-14, 09:18 PM
Aw geez... now in order to make shntool keep it in flac level 8 I have to find that post with that info on it, which now that I think about it I have no idea what level this was encoded at to begin with...

Is there a way to see at what level the flac encoding is was done? I think this came up before, but I have no idea what thread it was in... I'm going bonkers with this stuff. Bonkers I tell ya, BONKERS!!! :crazy:

Here you go!

http://www.thetradersden.org/forums/showpost.php?p=106889&postcount=33

feralicious
2005-04-14, 10:04 PM
Here you go!

http://www.thetradersden.org/forums/showpost.php?p=106889&postcount=33Thanks hon!

Hm, I'm not convinced that post is in English! I may just go the flac > wav > flac w/sector boundaries aligned since it's just for the last track and it's okay to do it for that.

pmonk
2005-04-14, 11:04 PM
I agree - sometime simple is better!

pmonk
2005-04-27, 11:08 PM
I'm not trying to make this more confusing, but it's not as simple as just fixing each disc separately, or fixing the entire show all at once. You should look at it from the perspective of musical sets. By musical sets I mean sets of music as played by the band, and you should look at fixing each set regardless of whether a particular set spreads over more than one disc.

So the first thing you look at is whether the show you have was played as a single set or as multiple sets by the band. You are almost certainly not going to want to fix an entire disc as a disc if there was a set break in the middle of that disc. Instead you will probably want to fix all the files of the first set as a set.

Also load up the last song of a disk and the first song of the next disc together in your computer's audio player and listen to the transition. Is it seamless? If the audio between two discs is actually seemless then that's a good reason to fix those files together because you want to preserve the seamless transition. If you were to fix your files on a per disc basis, you would end up introducing silent padding that will ruin the transition. You won't hear this if you burn the tracks to their respective discs, but the reason that this is undesirable is that you can never tell in the future how someone else might burn the tracks to a disc. CDs are getting longer all the time, and what was a good layout for the old 74 min discs may suck on 80 min discs, and be even more useless if 90 min discs catch on. Don't introduce a problem into your files that you or someone else will regret later when longer discs become the norm.

Confused? Well let's look at the show in question:

Disc 1 63:52.80
01 Intro 05:31.78
02 Bartender 08:10.92
03 When the World Ends 05:27.93
04 Busted Stuff 04:45.04
05 Two Step 09:18.04
06 Everyday 06:20.89
07 Grace Is Gone 06:48.74
08 Grey Street 04:22.85
09 Best of What's Around 06:09.04
10 Tripping Billies 06:56.80

Disc 2 66:25.45
01 The Stone 07:52.88
02 Gravedigger 05:14.02
03 Stay or Leave 05:34.52
04 Warehouse 09:44.97
05 Where Are You Going 05:05.50
06 Tim Solo 07:23.31
07 The Maker 06:21.22
08 Crush 10:02.57
09 Don't Drink the Water 09:06.46

Disc 3 69:21.95
01 Exodus > 03:22:01
02 Cry Freedom 06:39.50
03 Lie In Our Graves 10:52.22
04 Pay For What You Get 05:53.58
05 Tim Solo 07:11.31
06 Jimi Thing > 06:11.40
07 What Will Become Of Me 02:44.12
08 #41 06:43.05
09 Ants Marching 07:59.50
10 Nancies Intro 03:38.18
11 Dancing Nancies 08:07.08

I can't tell from this if there was a set break. Maybe there was a set break at the end of disk 1, maybe not. So load up Tripping Billies and The Stone in your audio player, skip forward to near the very end of Tripping Billies and listen to the transition. If it's seamless, then make a note of that. Do the same with Don't Drink The Water and Exodus. If the transition there is seamless you will want to fix those tracks together. I.e. if both transitions are seamless then fix the whole show together. If there is a fade out/fade in or some other obvious cut between each disc, then fix them per disc. If there is a cut at the end of disc 1, but discs 2 & 3 are seamless, fix disc one separately then fix discs 2 & 3 together. I hope this makes sense.

If you happen to know that there was a set break between, let's say, Gravedigger and Stay Or Leave, and the transition between discs 1 & 2 is seemless, then you would fix disc 1 AND the first two tracks of disc 2 all together.

Also, I do the same thing with encores. If the show has an encore I listen to the transition between the last song before the encore and the encore. If it is seamless then I fix the encore along with the tracks before it. But if it is not seamless, I fix it separately, which sometimes means just padding the end if it needs it and the encore is just one track.

One last thing I would say is it is better to err on the side of fixing the whole show at once than on fixing it it in parts, if you are unsure about what you are doing. If you fix it all at once the worst that can happen is that miniscule portions of one track will end up tacked on to the beginning or ending of an adjacent track. Although this is not technically perfect, it is essentially inaudible and is 'good enough' for most people (although maybe not for trading purposes). Whereas if you fix each disk separately but one or more discs were seamless, that seamlessness will be lost and if the tracks are ever burned to CD in a different layout than that proposed, a pop may well be audible between the tracks that were originally listed on separate discs. That's why you hear people say to fix the whole show at once. But being the anally retentive perfectionist that I am I never just run shntool over the entire show w/o considering set changes and encores.


Could this be an example of this??

length expanded size cdr WAVE problems filename
13:18.00 140767244 --- -- ---xx 770222-d1t01.shn
1:39.00 17463644 --- -- ---xx 770222-d1t02.shn
18:07.00 191746844 --- -- ---xx 770222-d1t03.shn
3:07.00 32986844 --- -- ---xx 770222-d1t04.shn
18:06.53 191694224 -b- -- ---xx 770222-d1t05.shn
14:23.00 152233244 --- -- ---xx 770222-d2t01.shn
8:11.54 86739452 --- -- ---xx 770222-d2t02.shn
5:18.21 56144636 --- -- ---xx 770222-d2t03.shn
6:02.46 63965036 --- -- ---xx 770222-d2t04.shn
18:16.61 193477916 --- -- ---xx 770222-d2t05.shn
3:21.43 35557580 --- -- ---xx 770222-d2t06.shn
10:00.69 106003052 -b- -- ---xx 770222-d2t07.shn
119:52.47 1210.00 MB (totals for 12 files, 0.6150 overall compression ratio)


http://www.thetradersden.org/forums/showpost.php?p=121956&postcount=13

irishcrazy2005
2005-04-27, 11:41 PM
Are the files listed in the etree database? Etc.

Just out of curiosity, what should I be checking the etree database for? When I get a show with SBE's I just fix it, re-FLAC it, and make a note in the text file that the SBE's were fixed with shntool. Is there something else that I need to do?

-Phil

pmonk
2005-04-28, 09:12 AM
Just out of curiosity, what should I be checking the etree database for? When I get a show with SBE's I just fix it, re-FLAC it, and make a note in the text file that the SBE's were fixed with shntool. Is there something else that I need to do?

-Phil

I think he was pointing out that not all sbe's should be fixed (i.e. see above)!

Five
2005-04-28, 09:30 AM
Could this be an example of this??

length expanded size cdr WAVE problems filename
13:18.00 140767244 --- -- ---xx 770222-d1t01.shn
1:39.00 17463644 --- -- ---xx 770222-d1t02.shn
18:07.00 191746844 --- -- ---xx 770222-d1t03.shn
3:07.00 32986844 --- -- ---xx 770222-d1t04.shn
18:06.53 191694224 -b- -- ---xx 770222-d1t05.shn
14:23.00 152233244 --- -- ---xx 770222-d2t01.shn
8:11.54 86739452 --- -- ---xx 770222-d2t02.shn
5:18.21 56144636 --- -- ---xx 770222-d2t03.shn
6:02.46 63965036 --- -- ---xx 770222-d2t04.shn
18:16.61 193477916 --- -- ---xx 770222-d2t05.shn
3:21.43 35557580 --- -- ---xx 770222-d2t06.shn
10:00.69 106003052 -b- -- ---xx 770222-d2t07.shn
119:52.47 1210.00 MB (totals for 12 files, 0.6150 overall compression ratio)


http://www.thetradersden.org/forums/showpost.php?p=121956&postcount=13
Just thought I'd mention that a SBE on the end of each disc (as is shown here) doesn't casuse any problems when burning to audio cdr but is good form to fix anyways in case of some future resequencing or in the event longer audio cdrs are invented.

feralicious
2005-04-28, 10:12 AM
And what uhclem was pointing out in that novella ;) was that you should check the show's setlist for a show like the one pmonk just posted the lencheck for since you may or may not want to fix both discs together. It depends on the set breaks. If it's all one set you should fix it together so as not to have the last track of disc 1 padded. If it is fixed separately and gets padded since it's the last track and then later someone wants to put d2t01 at the end of d1 there would then be added silence and it woulldn't be seamless.