Ok, today I was playing Sonic Spinball on my old Mega Drive, and noticed something odd at the start of The Machine level. On my Mega Drive 1, when Sonic jumps up into the launcher (very start of level), the noise keeps getting 'stuck' and is not a smooth slide tone like it should be. I tried the same cartridge on the Mega Drive 2, and the tone is smooth, as it is on the Wii Virtual Console version.
Why is this? Some sort of early YM2612 or 68000 bug that's been corrected on the MD2?
Project:The Final Zone, various hacking projects, Rockman World
It might be you're MD. Because my Model 1 slows down with games that use the GEMS Sound driver, to the point that sometimes they might freeze. (Which I have no clue why it does...) In your case though, it only affects the music.
Attachments appear to be disabled here, so I'm going to have to put the sound files on my server:
I tried several times and the audio lag on the slide tone was different every time; it's random. The MD2 has inferior sound quality, but the audio doesn't lag like it does on the MD1! What do you think?
Project:helping a local rock band; still a big Sonic & video game fan
I can't tell you why that is happening, but I can tell you I have heard that happen that way before. I don't even know which system I was playing it on when it happened. I think it might have even happened in the youtube video I posted of a playthrough a couple years ago.
I've had this many a time. I've only ever had a MD1 so I can't personally compare, I just always put it down to being one of the quirks of the game or console. It seemed to me at the time as if, especially in Spinball on The Machine level, that there were possibly just too many sounds going on at once to process and the console was just lagging. I'd often get the same thing with the teleporter sounds, they'd glitch now and again. It just adds to the character for me
The discrete YM2612 has a much more limited resolution for calculating the envelope than the versions built into the ASIC, and this results in envelopes with slow attack/decay to stay around for much longer (if not forever), depending on the volume at which the channel is playing. Didn't check the sound (the players aren't working for me...) so I can't tell if it's that, but there is an envelope-related bug.
That's for volume though, note slides should work just fine...
My guess is that something's stalling the Z80 since the entire song stops during the slide, not just that sound effect... but at that point data should already have been loaded so could it be the 68000 or a bug in GEMS?... Are we all playing with the same ROM?
This post has been edited by Andlabs: 23 May 2012 - 02:27 PM