ogg / compressing files

[coxjamir]

Hello,

I do a lot of recording on audacity and put the files into itunes so i can therefore put them onto my ipod, etc. I am running out of space.

I need to know how I can record these things (they are generally 20-27 minutes long apiece) as smaller so they take up less space. I know that ogg records them smaller but I have no idea how to do this and I do not understand computer jargon (or however you spell it). Is there anyone that can explain this or anyone that can suggest how I can compress these files but still be able to use them on a regular basis?? I am using a Macintosh... OSX 10.4.11.

Thanks!

[waxcylinder]

Are you putting WAV files from Audacity onto your iPod? If so then you are likely to run into space problems on your iPod.

Most iPod users will either use MP3 (you can export to MP3 with Audacity using the additional LAME software) - or you can use iTunes to convery your WAVs to Apple's AAC format. In either case you can choose the compression rate - 128 is normally regarded as the minimum for music, 192 is better and 256 is hard for most people to distinguish from CD quality. The rate you choose will depend on your ears and the amount of space on your iPod an the amount of music you have.

As a rough guide a 192 MP3 is around 8-10 times smaller than the equivalent WAV file. Note that bitrate for bitrate AAC gives better audio quality than MP3. Also note that WAV will give you the best audio quality of all as it is uncompressed.

You may find this page from the Audacity Wiki useful: http://audacityteam.org/wiki/index.php? ... s_and_iPod

WC

[kozikowski]

There's some difference of opinion how to deal with iTunes. I'm in the camp that says you need to deliver the highest possible quality sound to iTunes (WAV) and set iTunes preferences to produce the result you want. You can also use Audacity/lame to produce a very nice MP3 compressed song during production and tell iTunes not to mess with it at all.

The worst possible thing you can do is compress half-way in Audacity (WAV > MP3) and then compress it again (MP3 > AAC) in iTunes. Most common audio compression is destructive and you can't do it more than once. Compression damage doesn't add up. It multiplies.

<<<I do a lot of recording on audacity>>>

Live recording? That's what I use it for. What some people consider "recording" is pulling free, highly compressed, damaged audio clips down from the internet. The sound quality will never get any better than the worst step in the process. Processing squashed, bubbling, compressed audio at 48000, 16 bit WAV will give you a perfect file of squashed, bubbling, compressed audio.

Of course, if you were a good, patriotic, red blooded American, you would go right out and but a much larger iPod with your credit card.

Koz

[waxcylinder]

Of course, if you were a good, patriotic, red blooded American, you would go right out and but a much larger iPod with your credit card.

Koz

Hey, it's just like Jaws: "We're gonna need a bigger iPod ...."

WC

[coxjamir]

I will probably end up just getting a bigger ipod, but what about the memory on my computer? is it possible to buy more memory? lol...

[kozikowski]

<<<what about the memory on my computer?>>>

A few words about that. There are two different kinds of memory in your computer; actual internal memory which comes on 4 inch long circuit boards like this...

http://ralphlosey.files.wordpress.com/2007/06/ram.jpg

...and the hard drive which is much larger but much slower which looks like this...

http://en.wikipedia.org/wiki/Image:Hdd.jpg

The strips with the gold pins represent the memory in your head you use to recognize someone on sight at a party. The hard drive represents you not remembering somebody's name and having to drive home to look it up in one of your 3000 books. Both work, one is a lot faster.

You can throw money at Apple Servicing or Mac Mall or somebody like that and have them do an upgrade. Most Macs are built to be upgraded. You can do it yourself but you need to pay attention to your AppleCare Agreement. Some modifications will violate your agreement and Apple will not honor your free service.


As above. Microsoft Windows WAV format is uncompressed and completely undamaged. The files are huge, but there is no harm to the sound by using this format. WAV format quality is chosen at the beginning of your project and the quality will stay the same from then on.

MPEG1, Layer III (MP3) is an audio compression format that will produce small sound files at the expense of sound quality. Most MP3 tools have a slider you can adjust. [Small FIles--Sound Like Garbage] on one end and [Big Files--Sound Perfect] on the other. You get to choose. Most people want [Small Files--Sound Perfect]. That's not one of the options.

Apple Advanced Audio Coding (AAC) is a step up from MP3 because you can get smaller files at MP3 quality, or an MP3 size file that sounds much better. AAC is supported by Apple and is usually buried inside ITunes. AAC is the default iPod format and that's what you get unless you change it. It's a good trade-off given that you're usually listening on ear buds and can't tell perfect quality anyway and AAC can give you a huge number of nice sounding songs in a limited space.

OGG-Vorbis is yet another audio compression format about which I know almost nothing. Google it. I'm pretty sure you can't import OGG files into iTunes, but that will be part of your research. I don't think an iPod supports OGG.

You can play other tricks, too. I believe iTunes supports mono--single channel sound--as opposed to stereo. If you can put up with mono, that will double the number of songs on your iPod.

Koz

[waxcylinder]

You should be able to consider buying an external disk that you can plug into your MAC - and use this disc for your iTunes library. (I have no real MAC knowledge - but in PC-land we can plug USB discs into our PCs - you may be able to use Firewire or USB). These discs are fairly cheap these days my 250Gb discs cost c. UK£60 (US$120) from Amazon. 250Gb is bigger than the biggest currently available iPod. the Classic at 160Gb.

BTW: do not be tempted to use such an external disc for your Audacity project work - it is unlikely to be anywhere near fast enough (should be fine for iTunes though).

WC

[kozikowski]

And the compulsive engineer will raise his hand and tell you that safety backups require that your valuable work be on two different memory systems. Internal Hard drive and External Hard Drive, Memory Stick and External Hard Drive, On-Line-Backup and Internal Hard Drive, etc.

You can prepare a hard drive so it has two different "partitions" and looks like two hard drives, but that doesn't count because if the spinning platters crash, both partitions go in the toilet.

If your computer doesn't start one morning, you need to be able to point to a separate hard drive on the shelf in the sitting room and claim it has your safety copies on it. If you send your Mac to Apple Support for servicing, the hard drive will come back perfectly working but empty. Making backups of Audacity Projects is rough.

I can record off-air HiDef television programs and let me tell you how much fun making backups of that is.

Koz

[waxcylinder]

And the compulsive engineer will raise his hand and tell you that safety backups require that your valuable work be on two different memory systems. Internal Hard drive and External Hard Drive, Memory Stick and External Hard Drive, On-Line-Backup and Internal Hard Drive, etc.

Koz

Agree wholeheatedly Koz (as a compulsive IT person). My stuff sits on the internal hard-drive and two copies on two separate USB discs - plus my son in London gets a copy on his drives occasionally (he thinks he's getting access to my music - but really he's my off-site backup ......)

WC

[steve]

FLAC is a "lossless" compression format that will approximately double the amount of music that you can store on a hard drive. "Lossless" means what it says - if you convert a FLAC file back into a WAV file, the result will be identical to the original (uncompressed) file. FLAC is probably not supported by iTunes. It gives a compression ratio of about 2:1