Okay, decided to write this tutorial cause it's easy to do :P
Well... not exactly...

The advantages of this method over others:

• You can use stereo sounds (even stereo click sounds :P)
  
• Use longer/shorter sounds than before
  
• No hexing required

Okay then:
Contents

1. Creating your sound
   
2. Converting to VAG
   
3. Replacing in the RCO
   
4. Installing

Tools required

• A sound editor such as Audacity, Goldwave or SoundForge
  
• MFAudio converter (52.9KB)
  
• RCO Editor v1.11 or higher
  
• FW 2.50 RCOs or FW 2.60 RCOs (using opening_plugin.rco and system_plugin.rco; note, in the package supplied, a file 0pening_plugin.rco is given, this is the 3.xx opening_plugin.rco)

1. Creating your sound
You'll need an audio source of some kind.  Let's say wee're making a custom coldboot sound and wee're using the first few seconds of the song as our bootsound.  Open your song in your audio editor and delete everything that you don't need.  Now save this part as a 16bit 44,100Hz WAV (PCM) file.
If you want stereo sound, save each channel as a 16bit 44,100Hz WAV (PCM) file.  To do this, in SoundForge (for other programs, you'll have to figure it out yourself) click your mouse in the top channel so that the cursor is only in the top half, then select all of it.  It should look something like this:

Now press Ctrl+A then Ctrl+E - you'll have a new file opened with just one channel - just save this as a WAV, then repeat with the other channel.

Note: for custom bootsounds, although you can use really long sounds, it's recommended to keep it down to about 4 seconds.  The PSP cuts off the sound after loading a certain part.  So if your PSP takes ages to load up, I guess you could use a longer sound, but just keep in mind that long sounds take up a lot of flash0 space...


2. Converting to VAG
Now that you have your WAV file(s):

1. Open up MFAudio.exe
   
2. Click Open and select your WAV file
   
3. In the Output audio file » File Format listbox, select VAG - Sony PSX Sound - Compressed ADPCM
   
4. Click the Save As button and select where to save the file
   
5. Finally click Process
   
6. If you're making a stereo bootsound/click sound repeat the above with your 2nd WAV file

3. Replacing in the RCO

1. Open up RCOEdit.exe
   
2. Open opening_plugin.rco or system_plugin_fg.rco (the former is for bootsounds, the latter is for XMB click sounds).  Note, you must use a FW2.50 or FW2.60 RCO
   
3. In the list, scroll down till you see some [VAG] entries
   
4. Select the file you wish to replace, then click Replace
   
5. A dialog will pop up - select whether you want to make a stereo sound or not
   
6. Now just add your VAG(s)
   
7. Click OK

4. Installing
WARNING: this step involves flashing - do not attempt this if you don't know how to recover and know what you're doing etc etc.  I am not responsible if you somehow manage to brick

NOTE: I strongly recommend you having custom firmware - it's possible to semi-brick by flashing RCOs.

Now, this procedure depends slightly on your version number:

For 3.03 OE-C or later users

1. Enter recovery menu - if you don't even know how to do that, shoot yourself
   
2. Go to Advanced » Enable flash0 USB (or whatever it's called)
   
3. Connect your USB cable to the PC if not done so already
   
4. Go into flash0:/vsh/resource and copy opening_plugin.rco and system_plugin.rco to somewhere on your HDD - this is your backup copy - don't loose them!
   
5. Copy your modified RCOs into flash0:/vsh/resource overwriting the previous ones
   
6. Exit recovery mode and enjoy

For 3.03 OE-B or older users

I suggest upgrading to 3.03 OE-C or later - this makes things easier, but if you insist on staying at the lower firmware, figure out how to use PSP Filer...

Note: using a FW2.50 or FW2.60 opening_plugin.rco (custom bootsound) will cause PSX not to work, however there is a work around.  More info can be found in Ruttus' guide: http://www.psp-hacks.com/forums/viewtopic.php?id=74269

(This post was last modified: 03/03/2007 07:35 PM by ZiNgA BuRgA.)