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View Full Version : So I've Decided To Convert To Lossless...




Reeves
Mar 6, 2005, 08:56 AM
Is this a good idea? All my CDs are 128 AAC(174 so far). Can anyone estimate roughly how long this could take. Or how much HD space? Since 128 AAC is rougly 7.8 GB.



Blue Velvet
Mar 6, 2005, 09:08 AM
One of my favorite topics at the moment since I'm going through the whole process of re-ripping all my CDs (about 330).

I have done them in batches, letting them rip while I do other stuff on the Mac... have done about 200 so far over a couple of weeks doing a small stack of 10-15 each night and filing them in another bookshelf.

To me, the sound quality is worth the disk space.
2160 songs = 62gb (some songs are very long, 1hr in some cases)
Average CD is about 370-450mb.

However, if you have an iPod then you may find Lossless files put a strain on the battery (according to many threads here). My files get down-sampled to go on the Shuffle... a Shuffle-only feature at this stage.

howard
Mar 6, 2005, 09:08 AM
i would say roughly 40 gigs

WinterMute
Mar 6, 2005, 10:38 AM
There is absolutely no point in converting AAC or MP3 or indeed any compressed format to a lossless codec, you make no difference to the audio at all.

Lossless will only give you gains if you convert down from .aiff or .wav files running at 44.1Khz or above (where standard files are in the 30mb range).

If you are ripping standard Red-book CD's then lossless is excellent for preserving audio quality, but the price, as BV mentions, is a significant hit on battery performance and longeivity.

Do yourself a favour, don't bother.

MattG
Mar 6, 2005, 10:50 AM
Don't convert...there won't be any improvement. You'd have to re-rip.

A good question is how many CDs do you have total to rip? Maybe you should rip some of your favorite CDs in lossless, and rip the rest in some other AAC format? If you've got a LOT of CDs, that's going to take a *LOT* of space.

I've got almost 550 albums in iTunes...1000 songs that I've purchased from the ITMS, and the other 5300 songs on my computer are ripped from my own CDs at 320kbits. It takes up 56gb. I can't imagine how much space that would take up at lossless...To me it's a good compromise. The sound quality is fine, and I still have (some) space left on my computer!

Reeves
Mar 6, 2005, 11:21 AM
So should I just stay with 128 AAC?

Blue Velvet
Mar 6, 2005, 11:25 AM
So should I just stay with 128 AAC?

Unless you have the original audio CDs to rip to Lossless with...

Artful Dodger
Mar 6, 2005, 11:34 AM
Reeves
So should I just stay with 128 AAC?
I have mine set at 160 AAC but I don't keep most of the music that I have on cd on my Macs. I did notice the sound when a few were put up higher say at 192 AAC but thats just me ;) Does this really matter coming from an iPod? Or is the big diff. only from your home sound system?

combatcolin
Mar 6, 2005, 11:53 AM
And what happens when Apple release iTunes with AAC+?

Then i'll re import 5000+ songs at a lower bit rate and keep the sound quality, unless you have an expensive sound system and a good pair of ears its all a bit of a waste of HD space.

Yvan256
Mar 6, 2005, 12:15 PM
So should I just stay with 128 AAC?

If you cannot get a source of higher quality, stay with 128kbps AAC.

You can go from CD to lossless, or CD to MP3, or CD to AAC. But doing the opposite (MP3 to lossless, AAC to lossless) is useless and only wastes space.

Yvan256
Mar 6, 2005, 12:20 PM
And what happens when Apple release iTunes with AAC+?

Then i'll re import 5000+ songs at a lower bit rate and keep the sound quality, unless you have an expensive sound system and a good pair of ears its all a bit of a waste of HD space.

I already have difficulty telling the difference from AAC at 128kbps and 64kbps already for most songs. I suppose AAC+ will give me the following dilemma: keep my 3rd gen. 10GB iPod that now holds "20GB" or switch to a blue iPod mini that now holds "12GB" (which is still about "4GB more" than my needs).

The introduction of AAC+ would "double" the storage of all iPods and could lure 5-10GB iPod owners to switch to a brand new iPod mini. Especially if the competition keeps pushing 64kbps WMA in their marketing, Apple own't have much choice but to release AAC+.

I'd switch immediately if iTunes could re-encode to any given bitrate while transferring to any iPod (128kbps on PC, 64kbps on iPod). After all, AAC at 64kbps is still 44.1KHz, unlike MP3.

Blue Velvet
Mar 6, 2005, 12:24 PM
After all, AAC at 64kbps is still 44.1KHz, unlike MP3.

AAC at 64kbps sounds absolutely horrible. Even 128 is nasty...

Reeves
Mar 6, 2005, 12:42 PM
I do have all the CD's, but since your all talking about AAC+ I think I'll just hold off for that instead of uploading them all loseless and then 6 months or so later have to change it again.

Blue Velvet
Mar 6, 2005, 12:47 PM
I do have all the CD's, but since your all talking about AAC+ I think I'll just hold off for that instead of uploading them all loseless and then 6 months or so later have to change it again.

That's a big if... and when they're imported/ripped as Lossless then it's much easier to convert them to lossy formats like AAC/MP3 within iTunes. A couple of seconds to push the right buttons and sometime later they're all converted.

Besides, I have read more experienced posters say that AAC+ will not make that much difference for a CD file, only for streamed ones...

Why don't you just do your favorite 10-30 CDs as a test? If you're not impressed they're easy to convert to AAC...

Reeves
Mar 6, 2005, 12:53 PM
How do you convert lossless to AAC?

Blue Velvet
Mar 6, 2005, 01:09 PM
How do you convert lossless to AAC?

You set your iTunes importing preferences to the format you wish to convert to (AAC in this case, you choose the bit-rate).

Than you select the songs you wish to convert and then control-click on them which brings up a menu, one of the options will read 'convert selection to AAC'

Or you can choose the same option from the 'Advanced' menu at the top of the screen when in iTunes.

Reeves
Mar 6, 2005, 01:12 PM
OK, thanks for everyones help!

Reeves

blackpeter
Mar 6, 2005, 01:29 PM
While we're on this subject, I'm downloading live concerts from etree.org (relax, they're all LEGAL). Most of them are around 1GB per concert. Once I've converted the .shn files to .aiff, I would like to compress them. If I use the File>Import command and have Apple Lossless enabled, how much could I expect to trim a 1GB concert down to?

Thanks for any help!

Blue Velvet
Mar 6, 2005, 01:33 PM
If I use the File>Import command and have Apple Lossless enabled, how much could I expect to trim a 1GB concert down to?

Anywhere between 50-75% depending on the source material it seems.

Perhaps Wintermute or another audio genius will come and tell us what exactly determines these variable compression results.

Try a couple, see what happens...

blackpeter
Mar 6, 2005, 01:37 PM
Thanks Blue... So I can expect a 1GB file to go down to anywhere between 750-500MB?

Blue Velvet
Mar 6, 2005, 01:45 PM
Thanks Blue... So I can expect a 1GB file to go down to anywhere between 750-500MB?

Yes, it will possibly even fit onto a data CD for archiving.

Best thing is to experiment. You're not altering the original so it's worth satisfying your curiosity.

I have no regrets about going Lossless for the G4 -- since I buy all my CDs it's worth hearing them in the best quality and most convenient format.

Mind you, I'm also looking to buy 2 x 400gb internal HDs though (one for backup)

rasp
Mar 6, 2005, 02:58 PM
While we're on this subject, I'm downloading live concerts from etree.org (relax, they're all LEGAL). Most of them are around 1GB per concert. Once I've converted the .shn files to .aiff, I would like to compress them. If I use the File>Import command and have Apple Lossless enabled, how much could I expect to trim a 1GB concert down to?

Thanks for any help!

I'm guessing that apple loseless will be similar in size to shorten and flac, since those are also loseless formats.

And, this was a timely post on your part, I was just thinking about this site again and didn't remember the name.

Fredstar
Mar 6, 2005, 03:29 PM
I have started ripping my albums at AAC 256 because i reckon it sounds noticeably better than AAC 128, my question is when i play 256kbs on my 20gb ipod will it affect the battery life significantly?

WinterMute
Mar 6, 2005, 04:27 PM
Anywhere between 50-75% depending on the source material it seems.

Perhaps Wintermute or another audio genius will come and tell us what exactly determines these variable compression results.

Try a couple, see what happens...

I'll give it a go Blue, it has to do with the way the brain processes complex audio signals, we all suffer from a phenomena called "masking" which basically means we can't always hear quiet sounds as they are simply obscured by louder ones (or even HF sounds obscuring LF sounds)

Thats a simplification obvioulsy.

All compression codecs make decisions about what they think you can hear and prune the data-rate down to comply to that pattern, some better than others.

The lossless codecs work on the same principle (basically), so very complex musical arrangements can be "pruned" more heavily than sparse arrangements, so Motorhead will get reduced more than a solo guitar passage from Pat Metheny.

Give it a try, it seems to hold true across the musical styles.

WinterMute
Mar 6, 2005, 04:31 PM
I have started ripping my albums at AAC 256 because i reckon it sounds noticeably better than AAC 128, my question is when i play 256kbs on my 20gb ipod will it affect the battery life significantly?

Only very slightly I'd think, the probelm is when the filesizes get to the point where the disc is spinning up during a single song to load the next section into memory, sure 256 is twice the size of 128, so the disc (theoretically) is worked twice as hard, but id doesn't equate to a 50% increase in battery use, as the disc is only a part of the total load on the iPod's power system.

quackattack
Mar 6, 2005, 06:22 PM
Only very slightly I'd think, the probelm is when the filesizes get to the point where the disc is spinning up during a single song to load the next section into memory, sure 256 is twice the size of 128, so the disc (theoretically) is worked twice as hard, but id doesn't equate to a 50% increase in battery use, as the disc is only a part of the total load on the iPod's power system.

Yeah, it has to do with the buffer. iPod's have a 32mb buffer. Which mean with 128 or 256 it can fit a few songs into the buffer. With lossless they are often so big that the iPod cannot use it's buffer. Meaning it has to read straight from the hard disk. This kills batteries. While with 256 it will have to read from the disk slightly more often, you should not notice a big difference.

FrancisSawyer
Sep 20, 2005, 04:44 AM
"The lossless codecs work on the same principle (basically), so very complex musical arrangements can be "pruned" more heavily than sparse arrangements, so Motorhead will get reduced more than a solo guitar passage from Pat Metheny."

Incorrect. If that's how they worked, they wouldn't be lossless. Lossless means you can mathematically reconstruct the original file, bit for bit. These codecs don't throw away anything. I haven't studied their algorithms, but my guess is that they encode the slope of the waveform between each sample, instead of the sample values themselves.

The best you can hope for with lossless is usually about 50 percent compression.

The real question is why the hell Apple and others are still selling crappy 128 kbps music when we should be able to buy lossless. After all, it's still saddled with the same copy protection, so there's no excuse.

WinterMute
Sep 20, 2005, 05:45 AM
"The lossless codecs work on the same principle (basically), so very complex musical arrangements can be "pruned" more heavily than sparse arrangements, so Motorhead will get reduced more than a solo guitar passage from Pat Metheny."

Incorrect. If that's how they worked, they wouldn't be lossless. Lossless means you can mathematically reconstruct the original file, bit for bit. These codecs don't throw away anything. I haven't studied their algorithms, but my guess is that they encode the slope of the waveform between each sample, instead of the sample values themselves.

The best you can hope for with lossless is usually about 50 percent compression.

The real question is why the hell Apple and others are still selling crappy 128 kbps music when we should be able to buy lossless. After all, it's still saddled with the same copy protection, so there's no excuse.

Sorry, I was trying to make it a little less technical, when I say pruned, I don't mean stuff is thrown away, I mean the file-size gets smaller, and in fact it goes the other way in reality.

Truly lossless codecs are a thing of wonder, but only yield small reductions in filesize, and yes, the smallest you can expect is around 50%, many rock and dance tracks only reduce by a couple of hundred Kbps, hardly seems worth it.

Loge
Sep 20, 2005, 08:06 AM
The real question is why the hell Apple and others are still selling crappy 128 kbps music when we should be able to buy lossless. After all, it's still saddled with the same copy protection, so there's no excuse.

I would like to see this too, but the record companies would probably want to restrict the burn rights, since selling lossless would enable customers to burn an unprotected audio CD with the same quality as a purchased CD.

Loge
Sep 20, 2005, 08:10 AM
Yeah, it has to do with the buffer. iPod's have a 32mb buffer. Which mean with 128 or 256 it can fit a few songs into the buffer. With lossless they are often so big that the iPod cannot use it's buffer. Meaning it has to read straight from the hard disk. This kills batteries. While with 256 it will have to read from the disk slightly more often, you should not notice a big difference.

Can it not refill the buffer as the track plays? I have some very long tracks, which exceed 32MB, but I don't recall hearing the hard disk constantly spinning during playback (I could be wrong though). I thought that higher bitrate songs require more frequent disk access simply because 32MB represents less playback time. In practice I've used several different bit rates and not noticed any difference in battery life.