I'm looking at ways to free up some space on my laptop. Obviously music accounts for the majority of the data. 90% of it is MP3. Is space savings a benefit of mp4? Most of the crap I can find on MP4 is just how to convert from MP3. All I've found regarding benefits is that the container can be used for video and audio as well as it boasts a slightly better streaming capability.

erm... MP4 is simply an encapsuation iirc.... MP3 audio with whatever video codec you choose....

if you're looking to lighten the load and still keep the MP3s.... knock the bitrate down a bit.

yeah, just changing to mp4 seems to generally increase file size. I ended up just lowering all the bit rates.

final result... Mp3 is smaller than MP4 :)

...buy a bigger HDD.

buying a bigger hard drive isn't always the best solution. I'm more after speed than space.

convert them to wma's.

if its speed your after look into SATA.

yes, mp4 is a packet file that includes Video and audio data - Video can either be AVC or one other type of compression that I can't recall, and audio can either be mp3 compressed or wav (uncompressed), so at the very least you're adding on the side of the header that tells the mp4 player what type of audio and video is being used. Mp4 is a video with audio format, where mp3 is an audio only format.

buying a bigger hard drive isn't always the best solution. I'm more after speed than space.

Then buy a new 500 GB 7200 RPM SATA drive. The only thing faster in a personal computer is 10,000 RPM SCSI, and then you've got a cap of 160GB, and much much more expensive. It'd be cheaper on you to pick up a $20 SATA card, and a pair of 500 GB harddrives and run a RAID setup.

Honestly though, given the bitrate of data needed for mp3 encoded audio files anyway, you could add a spare 40gb junk harddrive just for video and mp3 files. You can stream HDV M2t files over a network connection pulling from a 5400 rpm drive in a fileserver - if you're having problems with mp3 playback, harddrive speed isn't the bottleneck.