Audio quality

[RCube]

Hello,

 

First of all I'd like to apologize if this is the wrong section to post this in. I've considered posting this in the bug section first at but it's not really a bug. It possibly belongs in the feature section although I am not certain if this is already possible and it's just me not knowing how.

 

Here is my problem:

 

I am trying to extract the music from a specific game boy color demo. This demo can be downloaded here (note: It's not anything commercial or anything, it's legal):

Pouet page.

<div><iframe width="459" height="344" src="https://www.youtube.com/embed/tp0ZqXNwt ... ure=oembed" frameborder="0" allowfullscreen="true"></iframe></div>
 

At first I wanted to use visual boy advance to do this but I quickly found out visual boy advance was not capable of correctly rendering the linked demo. (aside from video glitches it slows down the playback (including the music) significantly. This issue occurs at the "skull part")

 

After trying multiple emulators (some rendered correctly, but either slowed down too much when capturing or didn't have a capture option at all) I found out about VBA-M and fortunately this did render the demo correctly.

 

The problem I'm having is that the audio quality is less than the original visual boy advance and I'm not sure how to improve it. I run with a 44kHz sample rate on both emulators (with both I mean VBA and VBA-M) and I disabled sound enhancement in VBA-M. I also used all 3 different output API's but they all deliver the same result. The sound in VBA-M sounds "muffy" compared to VBA.

 

What is causing this exactly and is this changable? I thought it might be a low pass filter as VBA sounds similar to VBA-M once I turn that on there but VBA-M doesn't seem to have options for that. I tried copying those sections of the config file to VBA-M's config file but that didn't do anything.

 

Any advice is welcome.

 

Rcube.

[Squall Leonhart]

The sound in VBA-M sounds "muffy" compared to VBA

 

this is expected

VBA-M does the audio correctly (barring GBA channel 3) while vba only did it right when interpolation was enabled.

[mudlord]

vba-m uses bandlimited synthesis, hence the difference in sound to normal VBA. As a result, its not changable.

[Squall Leonhart]

and fyi, bandlimited is true to form of the hardware itself

 

the only differences are caused by the speakers and sound card in use providing more or less bass/treble