you know i was confused about that as well when i first submitted my hack. this is my first PSX project and I had ripped the game myself using imgburn and it dumped it into one .bin and cue file and that's what i was working with. then when i finished version 1.0 and submitted it to romhacking.net, i had it scan my ROM / ISO Information and it showed unknown and it was a genesis game or something. then DonPatchi edited my game entry noting that "This is PSX patch nothing to do with genesis no-intro rom info."
at first i didnt know who or what Redump was but i understand now. The way PS1 games are structured is they have the data track for the first track, and the rest are CDDA redbook audio tracks. Most PS1 games only have 1 data track, but some PS1 games use Redbook CD audio which adds multiple tracks. these games you can put in your CD player and it'll play those tracks. The games that dont have CDDA audio uses Sony's proprietary XA format and that's including in the data track.
that's why with some backup games when you try to play it on a real playstation using swap methods, it won't have any music because it uses the donor disc which doesn't have multiple tracks, or it has a different TOC (table of contents).
And many people load up PS1 games incorrectly inside a emulator where they load up the first bin track in a emulator and it doesn't play any background music. that's because they're supposed to load the .cue file. Preferably i would like PS1 games to come in 1 bin file to avoid confusion. But it's Redump's decision to seperate the tracks individually for PS1 and Saturn games.
But yeah the first track is the data track, and the rest are CDDA audio tracks. So you can patch it on a .bin that merges all the tracks together, or patch it on the first track.
up until March of 2021, there's never been a way to fully play PS1 games with CDDA audio other than with a modchip, using a PSIO type device, or swapping with the original retail game. but earlier this year a user named Socram discovered a exploit that unlocks the drive by using Tony hawk or another compatible game. the exploit is callecd tonyhax. This basically unlocks the CD Drive where you can lift the lid open and when you insert a backup it'll play whereas with swapping methods u would need to have something pressed down on the sensor to have it think that the lid is closed. Lifting the lid open will refresh the toc that's why the music plays properly.
what a coincidence that right when i was working on my NBA Jam 21 project, i had encountered this issue with CDDA audio not playing, then shortly after the tonyhax and freepsxboot exploit dropped. Oh and let me just say that freepsxboot only requires a ps1 memory card and i think that is more suitable. For some reason I notice a graphical glitch when using tonyhax during the Coaching tips screen, and it appears that the player profile portraits have some sort of double exposure when the portrait is mirrored but it displays properly with freepsxboot
Got it, I think lol. Yeah I wish redump wouldn't do things that way, but it is what it is. Thanks for the info!