Syntrillium Backup Forums :: View topic - MP3 "save as" degradation? & System perf Q

howdydooit · Location: USA Posts: 3

I have some very large MP3 files 250+ MB that I want to break down into individual tracks (cuts).

Basically - they are radio audio of certain events, with commercials edited out. I want to break them down into multiple cuts so that they are more manageable.

They were recorded in MP3 format at 128k CBR mono as one continuous file, and then saved. At some point, I reopen them (while I go make some coffee!), and then I basically break them down using the cuing list and then rename each "chunk" to save it. When I do a "save as" of this smaller file, I get a warning that I am saving in a lossy format, and do I want to proceed?

Does this process take the pre-existing MP3 and try to compress it again? Am I losing any audio quality doing it this way? Or is this just a default message CE2000 gives me.

Secondly, regarding system performance, these big files take a long time to open and also a long time to save or do anything with. I know I need a faster system, but when I upgrade, what do I pay attention to most? CPU speed? Disc? RAM? Sound card? etc.

Currently, I have a Pentium III 500, 320MB RAM, 60 GB 7200 rpm HD (ATA), and a Turtle Beach Santa Cruz sound card. I realize there are some things that would be optimum, like SCSI vs ATA or SATA, but I'm not looking to split hairs, just speed things up. Where would I get the most bang for the buck? I'm talking about a new system, not upgrading this one.

I just took the offer to upgrade to CE Pro, but am currently using CE2k.

ozpeter · Location: Australia Posts: 3200

Cool Edit handles mp3 files by converting them to (essentially) wave format and that enables the full range of processing to be carried out. If you then resave to mp3 you are recompressing with consequent loss of quality. There is mp3-specific software Out There which can perform some tasks losslessly (including, probably, file splitting) but not the range of transformations that Cool Edit can undertake.

I'll leave the question about performance to the hardware specialists here apart from saying that your soundcard affects audio performance (input and output, where these pass though it) but not processing performance. The more CPU horsepower you have the faster effects processing will be, and the faster your disks the more tracks you will be able simultaneously to record. Unusually large amounts of memory will probably only help with running unusually demanding effects processing (all of that is of course pretty broad-brush comment).

- Ozpeter

MusicConductor · Location: USA Posts: 1524

I second that. Recompresion does induce losses. There are freeware mp3 utilities that will cut the stream between frames (this doesn't always make for the smoothest cuts) and not require recompression and its related losses. It sounds like you'd be better off with that.

My two cents on the system specs, and that's all this will be worth, is that it depends on the type of audio you're doing. A fast CPU would be the main asset to making mp3s. A fast HDD would help doing large files and especially help multitrack recording. Lots of RAM is great for big multitrack mixes, particularly when you're using realtime effects.

howdydooit · Location: USA Posts: 3

Thanks for the idea of the splitter - I downloaded Mega MP3 Splitter... it worked fine! It was a little cumbersome to set the breakpoints with precision because the applet can't be sized to full screen - but I accomplished my mission, and will be looking for other freeware to experiment with. There was plenty that turned up in my search.

One strange thing, though... I started out with a 236 MB file, but my split cuts only total 221 MB. Gonna check to see if maybe I missed one.

MusicConductor · Location: USA Posts: 1524

Thank you for getting back to us on this!

howdydooit · Location: USA Posts: 3

Aha - missed one track at 9 MB - so my 236 MB file is now 17 tracks totalling 230 MB. That doesn't sound like a recompression, or does it? Is there any theoretical reason why a file would diminish in size by 2.5% after splitting it up?