Can one resolution increase the resolution up higher? Is one type of video or sound file superior in quality? What are the Optimum file types?
You can’t change the resolution, either higher or lower. It’s an LCD screen, they only have one resolution.
I can’t say if there’s a “best” video filetype, as I don’t use my Fuze for videos. But generally (for both audio and video), the higher the bitrate, the better the image/sound quality. Probably the best supported audio filetype is FLAC, as it’s lossless. Other supported audio codecs sacrifice quality for smaller file size.
Optimum is different for everyone. For some people, nothing less than the full quality of the CD is optimum. Those people need FLAC, which is called lossless compression–everything in the original music is there. But those files are big.
For many people, mp3–which is called lossy compression, as are .wma, .ogg and Apple’s .aac or .m4a (not playable on Sansa)–sounds good enough, and they can’t tell the difference between an mp3 file and a FLAC file that’s twice the size or more. And if you use lossy compression, you can get more music on your unit.
Just to make things more interesting, there are lots of gradations within lossy compression. mp3 can go up to 320 kbps (kilobits per second–how much information per second is in the file) or down to 16 kpbs, possiby lower. Most people think high-fidelity music starts at around 192 kbps, and some people want 320 and nothing less. But Apple sold 128 kbps files (in its own .aac format, different from .mp3 but lossy) for many years on iTunes to happy consumers.
So do you want perfect fidelity? Do you want excellent but slightly lossy fidelity with twice as much music on your player? (320 kbps) Do you want very good fidelity with 1.5x as much music (192 kbps). Do you want passable fidelity (128 kbps) that doubles the amount you can fit on your player? Are you using the player for audiobooks, which need much less information to sound good since it’s only a lone voice (64kbps is fine for many users).
There are continuing arguments over which format (.mp3, .wma, .ogg) sounds best at which bitrate. Each one throws out different information in order to be smaller. But those controversies are way over my head. .mp3 has enough possibilities for me, and it has the advantage of playing on every mp3 player.
You could experiment. Get Media Coder.
In its settings, you can convert files every which way. Take a favorite song on a CD and convert it to FLAC. Then convert it to mp3 at various bitrates. Put them all on your unit (you’ll have to use different filenames) and play them back. That’s really the best way to decide what bargain you are going to make between file size and fidelity.