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View Full Version : AAC vs. .WAV for IPod's


ed hochuli
2005-04-01, 06:45 PM
When "import"ing music to an IPod, which is the best quality??....a couple songs skip when i use mp4 (aac), but with .wav, nothing skipped...but to me they both sound pretty similar....any help would be much appreciated! thanx!
-peace
ryan

irishcrazy2005
2005-04-01, 07:04 PM
When "import"ing music to an IPod, which is the best quality??....a couple songs skip when i use mp4 (aac), but with .wav, nothing skipped...but to me they both sound pretty similar....any help would be much appreciated! thanx!
-peace
ryan

Well, it all depends on what your ear can hear and what sounds good to you. Inherently, wav is better than aac because aac is a lossy compression (like mp3). If you can't hear much of a difference, than I suggest that you use either mp3 or aac for your iPod because the files are MUCH smaller. Wav is a completely uncompressed file format. Another option for the iPod specifically is the apple lossless format (alac I believe). This is similar to SHN or FLAC (although not as good from what I hear). Either way, go with what is smallest in filesize and still sounds good to you.

-Phil

Disclaimer: This is for your iPod and personal use only, never trade lossy files!!!

ed hochuli
2005-04-01, 07:31 PM
Thanx phil!, that cleared up a few questions i was dealing with.....Real quick, so would u say the skipping is caused by the smaller file size??...(only 2 songs skipped out of 12 using mp4, but none with .wav.)....thanx again!
-peace
ryan

uhclem
2005-04-01, 08:11 PM
In what part of the song did the skip occur?

ed hochuli
2005-04-01, 11:11 PM
it skips in the beginning of the song....the last two songs of the cd....(it's a live show (.wav's converted from flac's))....thanx!

rherron
2005-04-02, 10:22 AM
I have had an iPod since the first model came out. Filled the first one and I recently bought the newest one (20 G) and have 3000 songs on it. I have never had a song skip on either iPod. The skipping has nothing to do with the format you chose. Something went wrong when you encoded it. Couldn't say what for sure.

I encode to AAC for the reason irishcrazy2005 mentioned -- size.

Rob

uhclem
2005-04-02, 12:52 PM
I agree that the skipping has nothing to do with the file size, or format per se.

Since this problem appears at the start of tracks, it might be a gap issue with AAC rather than a 'skip'. AAC files are, AFAIK, not capable of gapless playback unless they are put into an mp4 (aka .m4a) container during encoding.

I don't have an ipod but if I didn't I wouldn't use lossless files with it. The best thing to do would be to learn how to encode gapless AAC files inside an mp4 container.

DoIFeelLucky
2005-04-02, 01:57 PM
It doesn't matter if the AAC files are gapless; I don't think the iPod is capable of true gapless playback. Maybe it can crossfade, but that's not good enough.

And I dunno... it seems more likely that the skipping is a result of an error in the ripping process, and not an encoder problem. iTunes isn't as reliable a ripping program as EAC.

If you insist in ripping using iTunes for your iPod, I recommend using their AAC encoder. iTunes' MP3 encoder isn't really that great, but their AAC encoder is apparently the best (http://www.rjamorim.com/test/aac128v2/results.html) one there is for that format (as of 2004).

Just to note, iTunes Encode (http://otto.homedns.org:8888/iTunes/iTunesEncode46.zip) lets you use the iTunes AAC Encoder when ripping in EAC. I have not tried it yet, but I've heard good things. (iTunes Encode thread (http://www.hydrogenaudio.org/forums/index.php?showtopic=29821) at Hydrogenaudio)

uhclem
2005-04-03, 03:34 PM
It doesn't matter if the AAC files are gapless; I don't think the iPod is capable of true gapless playback. Maybe it can crossfade, but that's not good enough.

And I dunno... it seems more likely that the skipping is a result of an error in the ripping process, and not an encoder problem. iTunes isn't as reliable a ripping program as EAC.If the IPOD isn't capable of gapless playback then that could be the problem. (I wouldn't pay that kind of money for a player that can't play gaplessly.)

I can't tell for sure whether our friend is having true 'skips' or gap problems from what he describes. I agree that if he's sure it's a skip then he needs to rerip and rencode.

DoIFeelLucky
2005-04-03, 05:00 PM
If the IPOD isn't capable of gapless playback then that could be the problem. (I wouldn't pay that kind of money for a player that can't play gaplessly.)
I don't know of any portable that does gapless playback. It would be nice if a company made one, but sadly I don't foresee it happening any time soon.

wazoo2u
2005-04-03, 05:22 PM
I don't know of any portable that does gapless playback. It would be nice if a company made one, but sadly I don't foresee it happening any time soon.

Rio KARMA.

Plays FLAC and OGG too... only problem is limited (20gig) capacity.

willndmb
2005-04-04, 01:13 PM
iPod will always skip with aac and mp3
so if you don't want that then you need to do wav or aiff
but they will take but a lot more space

DoIFeelLucky
2005-04-04, 02:21 PM
I don't know of any portable that does gapless playback. It would be nice if a company made one, but sadly I don't foresee it happening any time soon.
Rio KARMA.

Plays FLAC and OGG too... only problem is limited (20gig) capacity.
I checked out the specs on Rio's website, and I found no mention of gapless playback - just a crossfader.

Back on topic... I wonder what the iPod's behaviour is with Apple Lossless. It's an inherently gapless format, unlike MP3 or AAC. Does anyone know about this?

rherron
2005-04-04, 06:08 PM
iPod will always skip with aac and mp3
so if you don't want that then you need to do wav or aiff
but they will take but a lot more space

Positively untrue. I have 2 different iPods with over 5000 songs between the 2, all in either AAC or MP3 (mostly MP3 on the old iPod, and a mix of MP3 and AAC on the new one). I listen to my iPod, on shuffle, in my car everyday (30 minutes each way to/from work). My best friend also has 2 iPods. He also encodes to AAC or MP3 and has not encountered this problem. I have just never heard one of them skip. Either has he. We have both had iPods for 3 years. Skipping is just not an issue. Something went wrong when he encoded to AAC. I suggest re-encoding.

Rob

RainDawg
2005-04-05, 12:37 AM
The iPod DOES skip, between songs. Listen to some music that is continuous (live a live set with aud noise) and you'll clearly hear a little click between the tracks. They have been informed of it, and by not fixing it for the past 2 years since I first heard people complain about it, Apple has proven they care more about flair than functionality.

The Karma DOES play gaplessly with both FLAC and OGG, and this feature is listed in one of the firmware revisions (forget which one). The first 1-2 firmware releases didn't do this perfectly for all files, but it has since been solved and works as it should. As far as I know, the Karma is the only portable that does this.

rherron
2005-04-05, 05:13 PM
I think I misunderstood. You are correct -- iPod cannot play back, say, a live show without gaps between the tracks. However, the tracks themselves do not skip, regardless of the format. I thought the implication was that unless one encodes to WAV, the tracks will skip. That is not true. Conversely, even if one encodes to WAV there will still be gaps (split second pauses) between tracks, so no live recording will sound seemless as it does on a CD or on a Karma.

Rob

geniusanyway
2005-04-05, 07:58 PM
Conversely, even if one encodes to WAV there will still be gaps (split second pauses) between tracks, so no live recording will sound seemless as it does on a CD or on a Karma.

This is not true. The skipping in between mp3 or aac tracks has nothing to do with the player and everything to do with the file formats themselves. The beginning of every mp3 or aac file is where the info for that file is stored (this is why when you download some mp3s and play them in itunes or winamp, certain information is automaticly displayed. This is what causes the gap no atter where you play them - ipod, rio or a burned cd. Not so with wav. Wav files will play seamlessly on an ipod, rio, etc.

wazoo2u
2005-04-05, 10:04 PM
Conversely, even if one encodes to WAV there will still be gaps (split second pauses) between tracks, so no live recording will sound seemless as it does on a CD or on a Karma.

This is not true. The skipping in between mp3 or aac tracks has nothing to do with the player and everything to do with the file formats themselves. The beginning of every mp3 or aac file is where the info for that file is stored (this is why when you download some mp3s and play them in itunes or winamp, certain information is automaticly displayed. This is what causes the gap no atter where you play them - ipod, rio or a burned cd. Not so with wav. Wav files will play seamlessly on an ipod, rio, etc.

I don't believe this to be correct.

There are gapless output plugins for WinAmp or Foobar that handle all the file formats. Assuming that your WAV files don't have sector boundary errors prior to encode, you'll have gapless playback regardless of the headers. What we're talking about here is the ability of other HARDWARE (iPod, Karma) to handle gapless playback, and THAT issue is a function of the FIRMWARE coding.

The point made above is that the iPod can't play back ANY file format without a gap.

This is a VERY, VERY complicated issue, and if you're interested, there's been a bunch of dicussion about it in the NeurosAudio forums www.neurosaudio.com (http://www.neurosaudio.com/) . Rio Karma supports gapless playback for FLAC playback, but I'm pretty sure that it offers gapless playback of ALL it's supported file formats.

feralicious
2005-04-05, 11:28 PM
I want a Neuros. :(

willndmb
2005-04-12, 01:31 PM
I think I misunderstood. You are correct -- iPod cannot play back, say, a live show without gaps between the tracks. However, the tracks themselves do not skip, regardless of the format. I thought the implication was that unless one encodes to WAV, the tracks will skip. That is not true. Conversely, even if one encodes to WAV there will still be gaps (split second pauses) between tracks, so no live recording will sound seemless as it does on a CD or on a Karma.

Rob
right
i was saying it "skips" between tracks
the songs do not skip but they play TAO in aac or mp3

BassmanRon
2005-04-12, 04:32 PM
I am not sure exactly how you're defining "skip." If you mean a brief but annoying pause while a song is playing, it could represent the iPod spinning up the hard drive and accessing more data from it to keep the music playing.

A friend of mine had to stop using his original 5Gb iPod to play back drum or bass tracks for live gigs because of that pause. Research on Apple's support boards found many users all reporting the same hiccup at something like 3:37 into a song. However, the rest of the circumstances and solutions varied greatly.

One solution was switching from big AIFF files to the much smaller MP3 or AAC files, which seems logical if the iPod is moving music data from the hard disk into RAM for playback. Exactly when the RAM gets flushed and reloaded from the drive, I'm not sure. (Between songs or at 3:37, whichever comes first?)

Switching to smaller lossy files wasn't an option in his case, once he heard how much better AIFF sounded. He ended up getting a minidisk player, which worked well except it was more clumsy to control on stage. (The iPod was velcro'd to the side of his standup bass.)

There were also people on the Apple board insisting they had identical circumstances and never, ever heard any sort of pause, hiccup, skip or whatever you want to call it.

DoIFeelLucky
2005-04-12, 05:59 PM
Switching to smaller lossy files wasn't an option in his case, once he heard how much better AIFF sounded. He ended up getting a minidisk player, which worked well except it was more clumsy to control on stage.
That doesn't make any sense at all. MiniDisk players use Sony's proprietary ATRAC lossy audio codec to store everything. It doesn't matter what your source is, it's encoded to ATRAC when it is stored on MiniDisc. And forget what you may have heard from Sony's marketing spin doctors, ATRAC is one of the worst lossy codecs in existence (http://rjamorim.com/test/multiformat128/results.html). So really, he did switch to a lossy format (and a poor one at that).

Your friend would have saved space and ended up with better-sounding lossy files had he stuck with the iPod and used LAME to encode his MP3s using one of the "--alt-preset" or "-V" switches.

BassmanRon
2005-04-12, 11:25 PM
That doesn't make any sense at all. MiniDisk players use Sony's proprietary ATRAC lossy audio codec to store everything. <snip> ... one of the worst lossy codecs in existence

If "minidisk" can only mean a proprietary Sony thing, then I used the wrong term. He had some sort of small unit that used CDs and allowed him to stick with AIFF files.

willndmb
2005-04-14, 12:22 PM
If "minidisk" can only mean a proprietary Sony thing, then I used the wrong term. He had some sort of small unit that used CDs and allowed him to stick with AIFF files.
a discman??

at any rate i never heard of this prob with the old iPods
the only time i have heard of any "skip" is between tracks, ie playing TAO

BassmanRon
2005-04-14, 12:52 PM
i never heard of this prob with the old iPods
the only time i have heard of any "skip" is between tracks, ie playing TAO

A lot of problems exist that you never heard of. That doesn't mean I'm making things up. I researched the problem over a year ago, when my friend asked my help in solving it.

Just now, it took me about 25 seconds on Apple's support forum to find a post from April 12 referring to the same phenomenon: "i found with my ipod is that on some songs the music skips once or twice (momentarily stops playing and continues on like nothing happened). can't find any info on what thats because of, if you had any ideas let me know."

That's what made his iPod unsuitable for drum tracks, too.