Hm.. so, to fade in/out music (or just change the global volume anyway), do you NEED that extra chip? Or can fading/volume also be done without that extra chip?

Another thing of interest:

Can this main chip also playback/loop OGG?

There's this issue about MP3 concerning loops. AFAIK MP3 can't loop without a small hickup, whereas OGG can. Naturally for games and demos, a seamless loop is quite important.

There is no OGG support mentioned in the document ( http://www.walrus.com/~raphael/mp3/MMC_version/vs1011b.pdf -> MP3 and WAV/PCM). Do MP3s contain keyframes? If yes, looping without hickups should be possible - but who knows...
After a quick look on the document again, I also couldn't find a "master volume" register, which you would need for fade in/out.

Hmmm.. to me it sounds somewhat silly to require a whole other chip just to change the volume, but alas.. I think changing volume is quite required for practical uses, it would mean that everyone's best served with the extra chip..

Wolf, you can use a external mixer for volume up and down, for example, simple volume controls on external speakers.... not? And I think you can do some controls by software...

You don't want external mixers/amps to control the volume..

If a game or demo wants its music to fade out, and other music to fade in, then you don't want to be forced to use an external mixer/amp for that. E.g. a text on screen: "press space and fade out please" and after that: "press space and quickly fade in please" ^_^

If it was only for EQ'ing or the spatial sound, then we wouldn't need this chip, but volume is so essential that we can't really be without it.. *unless* volume can be done with the first chip, then we don't really need the 2nd chip..

Ok, yes now I understand

Read that VS1011 document: it mentions a volume control register.

Ops, correct. I searched at the wrong place last time.

So, the first chip (e.g. the cheaper version of the card) can do volume? If so, there's little point in having the more expensive option, if you ask me..

If you have no I2C mixer you can still control volume.
But you need an external mixer to mix MSX sounds with the mp3 music.

Does the sound will be outputted to the (mono) TV?
Or does the cartridge have a line out connector?

There will be a jack or tulip output. (stereo)

so 2 speakers for this MP3 cart., 2 speakers for moonblaster, 2 speakers for the standard (and/or SCC) output. We could build a surround sound home theather studio with our MSX(!)

Quote:

There will be a jack or tulip output. (stereo)

So, clarify me, please, No monoaural output throught the pin on the computer?