I have some very important news to share with all of you regarding our project.
For those unaware, this project wouldn’t exist if it wasn’t for the incredible effort from a very talented developer at Deadfish Shitware which provided us, long time ago, with a custom made hardware VGM player which, thanks to the huge library from Project2612, enabled us to rip any games in the Mega Drive library.
What’s the big deal anyway?
I’ll try to keep it short: the VGM format is somewhat flawed because, either due to the format itself or the emulator used to log the VGMs (KEGA Fusion), the timing is off: that means different playback speed and, possibly, different pitch.
How did we manage to get around this issue? Thanks to the aforementioned custom VGM Player which has given us the possibility of playing back the VGMs at the correct speed and pitch.
The biggest issue which I’ve always been wondering about is: was the speed correction right?
At that time we didn’t have proper tools to check it so we had to do it with very limited tools and going by ear.
Today, thanks to MDFourier (link to our article) we’ve finally been able to measure the actual difference and the result is…
…we’ve been off by 0.0008ms (that is, millisecond) which, considering the length of a single frame on a Mega drive of 16,7ms equals to an error of 0,00479%.
Yes, we were absurdly close to perfection and I honestly dare anyone telling the difference.
Well, anyway, with that out of the way… the new VGM Player is now perfect down to each cycle. Yes, that 0,00479% difference is now 0. Null.
And wait, there’s more!
Thanks to MDFourier we’ve been studying where the source of all the noise in the Mega Drive is and, as we’ve always suspected, it comes from the VDP (Video Display Processor) and we’re now able to completely shut off the VDP during playback with an enormous advantage in noise floor.
See it for yourself:
What you’re seeing is the difference in noise floor between our old VGM Player and the new one: we have almost halved the noise and without the need of any hardware modification which means we’re still staying true to our own rules!
The obvious downside to this is… well, the screen is black during playback, of course. With the VDP completely off there’s no video output, obviously.
The new VGM Player is already available in our guidelines and all our contributors are strongly encouraged to update to the new one.
Also, the guidelines have seen some important updates and are now hopefully clearer and easier to follow.
And now, for some shoutouts:
First of all, we want to thank Artemio for his incredible work with MDFoufier: without this fantastic tool we wouldn’t have been able to confirm our hypothesis on noise source, get the correct playback speed down to each cycle and much, much more.
And then to FirebrandX who put a lot of effort in making a proper VGM rip of the MDFourier test. Without his work we wouldn’t have been able to properly test both the old VGM Player and the new one. This VGM is now included in the VGM Player download and, if you are a contributor, you’re welcome to send in your MDFourier recording and we’ll publish the results along with your recordings so that people will know how little the difference is between our contributor’s Mega Drive/recording chain and ours (spoilers: I’ve already done some tests and the differences are indeed very small).
Finally, to all the people working on the MDFourier project, both by actively developing it and testing it. Our project has made a huge leap forward thanks to them.
That wraps it up, hope everyone is alright out there and we’ll see you soon with another community release!