I can't made up my mind between the 4 principals (I think) audio format : MPC MP3 AAC or OGG.

My probleme is that I want a lot of caracteristics :

- Good audio quality ( I think it's not really a problem, even for MP3@192kbps) ;
- gapless (of audio format AND of players) ;
- implementation of Replaygain or equivalent (id. : of audio format AND of players) ;
- compatibilities with hardware players ;
- compatibilities with majors audio software (Nero and so on).

Basically, I want to rip my CD with EAC and a good codec to obtain a "clone" : good audio quality, gapless and so on.

I would like to play it in a DVD platine like MP3 CDs, and last but not least, I want to be sure that I will always ba able to play it in five or ten years.

I used to encode with MPC wich was nearly perfect , but now I'm afraid by lack of compatibilities and by the fact their is no more devellopment (because there is only ONE man working on it).

If can help me in order to choise...

I can't see any format matching all of your requirements, but MP3 seems (at least to me) to the format that matches the most of them. Maybe you need to figure out what is the most important for you and make a choice based on that. Maybe also you would like to consider ripping to a lossless format for archiving. Then you convert to whatever lossy format that suits you best for the time being. Thereby you need not to re-rip if you want to switch format in the future.

maybe you're right, maybe lossless is the best solutuion.
It's apity because a good encoded lossy sample is transparent to me at, say, 192 kbs. Lossless are about 800 kbps (more or less I think)

My HD will be full tomorrow at these bitrates !

MP3 is an attractive solution but : it's not really gapless, quality is not as good as newer codecs and will it be alive in 10 years ?

Not sure what you mean with "not really gapless". MP3 stores the correct lenght in a tag in the file, and the player must be aware of that to work well (and also be smart about not resetting things). All codecs (including vorbis) work that way...

Not really gapless because MP3 has to be encoded with a multiple of a precise number of frame (1152 I think). So MP3 tags store the number of frame to "cut" at the begining and at the end of the file. Theorically this is true gapless, but I assume that a lot of softaware players (almost all except winamp ?) and almost all hardware players (like DVD based players) doesn't read these tags. I would be happy to be wrong but I think that gapless playback of MP3 is only possible on foobar.
So no real gapless for MP3.

I don't know the exact situation for AAC but for exemple iTunes AAC is not gapless (I think) and the iPod is not a gapless player.

MPC and OGG are truelly gapless, on software players, but i don't know situation about HW players. And there is not a lot HW players for OGGs and not at all for MPC .

Same goes for any transform based codec (MP3/AAC/WMA/MPC/OGG/AC3/...) - they are all working on "frame-by-frame" basis.

Difference is that in standards like MP3 or AAC - "gapless" tags are not really part of the ISO specification of the standard (I always wondered why they didn't think about this, at least in the MP4 container) - and, some other formats - that are not international standards, like Vorbis - have this tag in their original specs.

So, basically - since all Ogg/Vorbis players are based on the reference Vorbis decoder (floating point or Tremor) one would expect that they decode file with exact number of samples.

With AAC/MP3 - one have to take care that his decoder reads correct tags - which is sometimes not the case, especially when it comes to DSP/Hardware decoders written by third parties.

We at Ahead will support any licensee of the Nero Digital Audio (AAC) decoder with what is needed for gapless in the decoder (FAAD2) - however, implementator of a device must ensure that there is no additional delay between file playback, etc..

That the point !
Why gapless tags are not part of the specification of AAC ?
We can apologize MP3, it is so old...

All the problem of compatibilities will obliged us to use, again and again, MP3 else than others newer and better.

Winamp's in_mp3 does not read these tags.
People have reported that gapless playback is supported with recent versions of in_mpg123, but I can't confirm this.
I don't know of any hardware player, which supports gapless playback for any format.

My wild guess - nobody (inside commitee) asked for it

One problem is, gapless signalling is not really a responsibility of AAC stream, but MP4 container instead - probably the industry demand for gapless playback is very low in general.

I might see what could be done on the next MPEG meeting in Seattle.

The Rio Karma supports gapless playback perfectly with all its supported formats (including vorbis, flac, wav and even mp3 if they include the appropriate lame tags). The only problem I've heard of (and never experienced myself) is occasional gaps between very high bitrate vorbis files (higher than -q 7). It also supports WMA, but I can't verify that it can play them gaplessly.

I should also mention that this player is awesome.

While it is not really worth mentioning compared to the other formats here, ATRAC is also truly gapless, including when played on a minidisc or an ATRAC CD player, and has been for many years. It's one of the few things Sony got right.

Den.

Which one? I briefly owned a D-NE710 and it was far from gapless in ATRAC mode: it inserted 3-4 seconds of silence between MP3 or ATRAC3/ATRAC3plus tracks (which partially contributed to my having sold it). Granted, the very latest models may have changed; mine was bought about this time last year.

MD players have always been gapless, as are Sony's memory stick players.

I don't speak from experience, but I have been told by an owner that his DNE300 is gapless, but only ATRACplus (not MP3) and only if a certain mode is switched on, which spins up the CD and loads the next track on the play list while the previous one is still playing.

The manual for the same device also states the same, but I must stress I don't speak from personal experience where clearly you do.

I'm actually glad you raised it, as I have vaguely toyed with buying one of the lower end Sony DNE series as a cheap second player for native mp3s, but have decided to leave it for now.

Later,

Den.