About 2:02 sec gap on SCD Game

[pnkiller78]

Hi, in this game
AH3 Thunderstrike (U) for SegaCD, recently dumped by hudgens I noticed that there are two tracks at the end that has 2:02 seconds pregaps, I checked the contents at the beginning specific tracks, and there's there data, the first two sectors has data that appears to be the end of the previous tracks.

I know that hudgens wrote in this thread that he checked the subchannel data for those tracks and apparently that it's the pause for the tracks, but I was wondering why the disk has think kind of behaviour if, at least for me, it is obvious that the first 2 sectors of those tracks (10, 12) belong in fact to the end of tracks 9 and 11 respectively.

What you guys think?

[huygens]

You're right! I didn't notice that. I did check the subcode and it indicates 2.02. However it seems to me the main channel data should take precedence.
Here the hash info for tracks 9-11 with 2.00 gaps. I think a mention of the bad gap data should go in the notes section for anyone dumping the disc in future.

Code: Select all

rom ( name "Track 09.bin" size 25081728 crc 5628c115 md5 94dfc125229751d6aaa9ddcfe568e0a4 sha1 c33746fefac948422c1e09b078197f926126db1f )
    rom ( name "Track 10.bin" size 44243472 crc 9d3182e4 md5 1f3dde9fd843b3c0cd3c852a365db331 sha1 4e09abb19a84d538679e511707af1ec803a66ab4 )
    rom ( name "Track 11.bin" size 52945872 crc e518bd5e md5 097ed5cb6a2e3683370aa38a50a33c73 sha1 5fa4d66e21bcaccf8289e586be1ef643fc57df2d )
    rom ( name "Track 12.bin" size 1902768 crc 61aa9edc md5 47fa258e0d27c876d83bb5e07cc039ce sha1 7dd140fd6165c3c9ec67013baad05e2c88b2f1fa )

[asapy]

The one on TOSEC has the completely same pregap.
I think the 2.02 pregap is right, imho.

Even if the first 2 sectors seem like the last 2 sectors of next tracks, I think, EAC value is ok.
Or, we need to recheck and redump all weird pregap games with hand.

[F1ReB4LL]

You can try to rip it with the CloneCD and pass the .sub to Dremora, he likes to analyze such cases ^_^

[pnkiller78]

The one on TOSEC has the completely same pregap.
I think the 2.02 pregap is right, imho.

I think that is because they must use EAC to dump the audio, too.

Or, we need to recheck and redump all weird pregap games with hand.

Those gaps are totally weird...

There's a lot of dump that has this same problem. Huygens, have you tried to dump the disc with PerfectRip???

[Jackal]

Something tells me that Final Fight dump has all wrong gaps unless of course the subchannels are like that

[huygens]

I don't think it's an issue with EAC. The subchannel check I did was on a .sub file extracted with clonecd. The "actual" (specified in the subchannel data) gap is 2.02. However the audio data suggests the gap should be 2.00. The question is wether to correct a mastering error or keep the data formatted the same as on the original media. It seems more in keeping with the project to keep the format consistant with the original media.


I was wondering about Final Fight myself.

[pnkiller78]

The subchannel check I did was on a .sub file extracted with clonecd. The "actual" (specified in the subchannel data) gap is 2.02. However the audio data suggests the gap should be 2.00. The question is wether to correct a mastering error or keep the data formatted the same as on the original media.

I think huygens is right, that this is a matter of what the project is trying to pursue, authenticity according the original media, or info based on what the data should be according to mastering standards.
I feel like the spirit of the project is the original media thing, but also feel a little bit uncomfortable about dumps that doesn't seem to be right, just my two cents.

What the administrators think about it?

[Rocknroms]

About this problem, I recovered quite all audio tracks for both (U) and (J) from (E) tosec dump of Shining Force CD using EAC+DaemonT+offset correction+etc.
Japan audio tracks are ok, but USA ones have data at the beginning of every track (03-35). The ammount of data is near 1sector/2352bytes that is the difference in pregap -> USA 2.00 - JAPAN 1.74. Probably also the difference of the 2 offsets (+1971).
Japan tracks end with only some bytes of silence 0x00 so this difference in pregap-offset moves data to next track.
Listening to USA audio tracks you don't hear any distorsion at the start.

If offset+pregap of USA version are right, there's nothing to do, they were mastered this way.

[gigadeath]

Something tells me that Final Fight dump has all wrong gaps unless of course the subchannels are like that

Those are the gaps returned by EAC and PerfectRip, in Tosec they're like that too. They're just about as wrong as the tracks we're discussing in this thread, in other words they're surely wrong, but only because they come from bad mastering, all of them should be 2.00.