News: 11 March 2016 - Forum Rules

Author Topic: Is it possible to remove or add sound effects in a SNES rom?  (Read 2575 times)

ValcristRoda

  • Jr. Member
  • **
  • Posts: 3
    • View Profile
Hello! First post here, so bear with me. I don't have any experience in romhacking first and foremost... but I'm curious if it's possible to remove a sound effect entirely or to replace one with another for SNES games. As much as I'd love to play Shin Megami Tensei 1 remake, it's really difficult for me to deal with the confirm sound effect every time I advance the dialogue. Most people don't have misophonia, but I do and.. well.. this game definitely triggers it hard.

Thanks for reading.

Jorpho

  • Hero Member
  • *****
  • Posts: 4949
  • The cat screams with the voice of a man.
    • View Profile
Re: Is it possible to remove or add sound effects in a SNES rom?
« Reply #1 on: July 22, 2020, 11:17:32 am »
Of course it's "possible". Many things are "possible".

Many SNES games use something called Bit Rate Reduction compression (BRR) for audio samples, and it's relatively easy to find BRR samples in a ROM and even replace them – provided the replacement data is the same size. But that would be for things like digitized speech. Something like the "confirm" sound effect is likely synthesized – meaning it's generated by code that is buried somewhere in the ROM and is indistinguishable from any other code.

May I suggest:
The Newbie Package of REQUIRED Material
 
ROMHacking.net FAQ: You ask, we answer!
ROMHacking.net Getting Started Section: Newbies Go HERE!
ROMHacking.net Documents Section!
How to ask questions the smart way.
On the Essence of ROM Hacking
Talk with experienced people in our IRC chat and ask specific questions there.
This signature is an illusion and is a trap devised by Satan. Go ahead dauntlessly! Make rapid progres!

FAST6191

  • Hero Member
  • *****
  • Posts: 3239
    • View Profile
Re: Is it possible to remove or add sound effects in a SNES rom?
« Reply #2 on: July 22, 2020, 11:18:13 am »
3 main approaches

1) You remove the trigger of the item in question.
2) You find a way to silence the effect. Many systems will have a software volume of some form (which most games for most of them I have ever seen will be left full volume or half on rare occasions) but looking at hardware here then anything will be software (and the SNES has its own audio processor setup so eh).
3) You break the sound somehow -- if it starts off as a microsecond of silence or whatever then you might be able to loop that back, or call it the end of the file immediately after that.

Most of those are "once you found it then it is easy" but the finding it part is potentially harder than you might care for in a first hack. For some later systems you will have an easier time but while this got ported a whole lot most of those will still be Japanese (and apparently the GBA version is a nightmare to hack).

1) After you press the button a whole chain of events will happen, one of those will be the sound. I don't know what we are suggesting for the SNES equivalent of https://tasvideos.github.io/fceux/web/help/fceux.html?TraceLogger.html these days but such a thing should do here if you can find an equivalent (should be one but I am not so familiar with the current SNES debuggers). The idea will be sit at the last point on the menu before the sound is called, start it logging and allow it to experience just sitting there doing not a lot (any background audio, animations... will happen over a few seconds), now say what happens next is what I care about, press the confirm button and then what new stuff happens to be sending data off to the sound chip or if the sound chip reaches out and touches something you have some idea of what is going on, you then either prevent the call from ever happening or change the call to jump to the end of its own little bit).

2) Volume does not appear to be a thing in the articles I just read on the SNES audio ( https://mechafatnick.co.uk/2016/08/19/the-mysterious-legacy-of-the-snes-soundchip/#player1?catid=0&trackid=0 https://megacatstudios.com/blogs/retro-development/creating-music-and-sound-for-snes-games-a-crash-course-in-snes-gss https://en.wikibooks.org/wiki/Super_NES_Programming/SPC700_reference https://en.wikibooks.org/wiki/Super_NES_Programming/Loading_SPC700_programs ) so you get to find what generates it and convert that to silence. Might be a nice little wave file you can replace with silence.

3) That will see you want to understand the loop/function that runs that you might have found in 1) and alter accordingly. Technically it still plays but without getting too philosophical if a sound effect makes no sound did it ever play? Answer is probably yes if you care about memory and CPU but if you mainly only care about not having your teeth set on edge then hey.

phonymike

  • Jr. Member
  • **
  • Posts: 58
    • View Profile
Re: Is it possible to remove or add sound effects in a SNES rom?
« Reply #3 on: July 23, 2020, 10:59:22 pm »
There's an old program called SNESSOR v2.1 which can rip and insert SNES sound samples. It's a DOS command line program (from over 22 years ago lol), it will not run under Windows so you'll need to run a DOS emulator first like DOSBox to run the program. It's not an easy task, but it's another option for you. SNESSOR 95 might run in Windows, but it can't insert sound samples.

Jorpho

  • Hero Member
  • *****
  • Posts: 4949
  • The cat screams with the voice of a man.
    • View Profile
Re: Is it possible to remove or add sound effects in a SNES rom?
« Reply #4 on: July 24, 2020, 11:32:05 am »
There's an old program called SNESSOR v2.1 which can rip and insert SNES sound samples.
That is for BRR samples, as discussed above.
This signature is an illusion and is a trap devised by Satan. Go ahead dauntlessly! Make rapid progres!

ValcristRoda

  • Jr. Member
  • **
  • Posts: 3
    • View Profile
Re: Is it possible to remove or add sound effects in a SNES rom?
« Reply #5 on: July 24, 2020, 04:56:38 pm »
Thanks for the information, everyone. I appreciate it.

peixemacaco

  • Jr. Member
  • **
  • Posts: 77
  • 70 65 69 78 65 6d 61 63 61 63 6f
    • View Profile
    • Old peixemacaco site found
Re: Is it possible to remove or add sound effects in a SNES rom?
« Reply #6 on: August 02, 2020, 12:24:26 pm »
There's an old program called SNESSOR v2.1 which can rip and insert SNES sound samples. It's a DOS command line program (from over 22 years ago lol), it will not run under Windows so you'll need to run a DOS emulator first like DOSBox to run the program. It's not an easy task, but it's another option for you. SNESSOR 95 might run in Windows, but it can't insert sound samples.

Yes, phonymike, I had used to change a sound in International Superstar Soccer with success...thought , I didn't continued... Must continue someday...

Me and T.A. Marcos (Fifa 2020) are changing Sega Genesis/Mega Drive sounds...

Success for you , ValcristRoda

Nelson
Super Monaco GP... It garnered an at-the-time unprecedented 10–10–9–9 rating from Electronic Gaming Monthly's Review and wasn`t a F Indy title.