Tom L

90% of my iTunes songs are mpeg-4 ALAC (iTunes v7.4.3.1) format. A few are mpeg-3 (mpeg1 layer III).

The meg-3 songs play fine. The mpeg-4 songs display on the MMI – song is damaged. And the following song names become grayed out.

I thought the MMI would read mpeg-4 files. Is it the ALAC format that is the problem? Or something else that I don’t notice.

I have read dozens (maybe a hundred) of threads trying to figure out how to get the songs from iTunes to a SD card to MMI in a good format. Clearly I am not technologically advanced enough to figure this stuff out!

As suggested here, I downloaded the program Mp3tag, but all I’ve been able to figure out what to do with it is to add the album art to the song file tag.

Can anyone help me figure out if I have a formatting problem and how to correct it? Hopefully there is a way to bulk change song tags.

Thank you for your help. This has been a several week project so far.

robodoc

Yes, this can be confusing and I struggled with this exact question when I first got my Q5. Not sure if you saw my thread here, but there is a discussion about this problem. I believe that the ALAC format refers to the Apple Lossless format and it is not supported by the MMI. You will need to convert those files to AAC. What's confusing is that both ALAC and AAC generate files with the same extension--both are mpeg4 type files, but they are not identical. On page 2 of the thread above (second to last post) I mention a great program that I now use to convert the files, but it is for the Mac. Not sure what you use, but if it is a Windows machine, I think that you can use a program that was also mentioned in that thread called dBpoweramp.

I now keep two types of files on my hard drive: the ALAC version, since they are of higher fidelity (better for playing on home theater) and in another folder, I keep the AAC versions for transfer to an SD card for the Q5. As an aside, I've uploaded the contents of the SD card to the Jukebox, but it seems to completely change the directory structure. There are likely some advantages to the Jukebox, but at least for now I prefer just accessing songs via the SD card. As an example, I can put all Jazz albums in a Jazz folder on the SD card, but that doesn't seem to port over to the Jukebox.

snagitseven

Audi doesn't directly support digital lossless files.The only way to play Apple lossless files is with an iPod/iPhone connected to either an Apple 30 pin or composite AMI cable. Since the MMI uses the analog output via these AMI cables from the iDevice's DAC, it doesn't matter what file format is used in the device. Otherwise, as robodoc pointed out, the lossless files cannot be read from any of the other sources including an SD card, Jukebox or USB/AMI cable, all of which are digitally processed with the car's own DAC.

Tom L

Thanks, Robodoc. Your earlier thread is very helpful. There is a link to an iTunes help page that talks about bulk re-coding with iTunes. I use Windows 7, would the Dbpoweramp program be better. I will give them a look tomorrow.

For use with the MMI what is the best format to change to; considering file size and sound quality? I have it set for MP3 at 192 kbps. Would ACC at 256 be better or what would you suggest?

Have you had any luck with expanding your folder setup on your SD card? Can you use playlists or are you just using: artist-album-song.

GregH

For MP3 at least, set 320kbs for the quality, not 192. This will require re- ripping your CD's from scratch. File size will be larger but audio quality will be a lot better. I believe AAC at 256 is comparable with MP3 at 320. In a moving car, questionable whether even an audiophile is going to know without guessing which format is in use at these bit rates.

TonySCV

It's most definitely noticeable to a human ear in music that contains a lot of "information" (e.g. electronica/dance/trance) where even 320kbps MP3's music information loss is very noticeable vs. a lossless codec.

FWIW, as snagitseven alluded to, the Audi MMI iPod/iPhone interface does a bit of unnecessary conversion to the music before it even gets to your ears, as the MMI won't pass digital output directly from an iPod. It uses the iPod's DAC (which is pretty decent, but still a step that shouldn't be necessary) to convert digital music to analog, passes it to the vehicle where it's converted back to digital and then converted back to analog again for the speakers. Not the most efficient way to go (and generally one of the reasons I'm hesitant to spring the big bucks for the B&O Advanced sound system in the A6, A7, A8, etc. as it seems a little silly to spend $5,000+ on a set of high end speakers that are hooked to an iPod via what amounts to a glorified analog iPod headphone jack listening to twice-DAC-converted audio. Lossless or otherwise.).

The SD card interface does support direct digital to the car (only one DAC conversion vs. 2), but it doesn't support lossless (again, an unnecessary annoyance Audi needs to address).

I have read murmurings online that the new generation MMI debuting in the A3 (in the US) has lossless support on at least the SD interface, but I haven't seen any credible confirmation of that.

snagitseven

Tony, the B&O, using the digital transport MOST system on all Audis these days, will allow full digital signal transfer from the SD card or Jukebox to the amps' outputs, avoiding the double DAC process, as you wrote, using the analog output AMI. As this is the Q5 forum, I don't want to get into a long discussion of the benefits of the pricy, C7 B&O (more than enough threads on the subject in the C7 forums) but I'll say that after extensive listening tests, I hear a significant difference with my C7 B&O in dynamic range and frequency response using MP3 320 or AAC 256 vs any format through the AMI despite car/road noise. I also had the much less expensive, great value B&O in my B8 A4 and found similar differences (the C7 B&O does trump the B8 B&O; no surprise for the price difference). In any case, I agree that keeping the signal in the digital domain as much as possible through the use of SD card/Jukebox with high bit MP3/AAC file formats will yield a better result than the analog processed AMI, even using Apple lossless files on an iDevice.

Tom L

Snagitseven, should I still record CD's into iTunes with Mpeg-4 ALAC (where file size doesn't matter)and then convert songs to Mpeg-4 ACC 256 for use on the SD card - or is it high enough quality to record CD's into iTunes at the ACC 256 level or Mpeg3 320. Thanks.

robodoc

I think it depends on what you want to use your iTunes for. If it will be only used for an ipod type device or the Q5, then I'm guessing you might not hear the difference between the ALAC and AAC (of course you can just do the experiment). If you plan to ever listen to music on a home sound system using iTunes, it might make sense to continue using ALAC and then convert to something "lossy" like MPEG-4. Also, it sounds like you have already burned lots of CDs using ALAC so doesn't make much sense to redo that.

In answer to your other questions:

FYI-there is a good brief discussion of ALAC in Wikepedia.

Not to hijack the thread, but if someone could comment on the way the Jukebox arranges songs that are uploaded from the SD, that would probably be helpful to several of us. And related: what is the advantage of using the Jukebox over the SD card?

newmoon

I would keep your 'master' library of music on your computer in ALAC or any lossless format, and make an additional copy in AAC 256 kbps for your Audi MMI.

That way, when you inevitably get a new car/iPhone/etc, and it supports some fancy new codec like Mpeg 5 or whatever that promises better sound quality and/or smaller file sizes, you can just make a copy in that format from your master lossless library.

It is a big no no to transcode from one lossy format to another, so if you had your master library in AAC or mp3, then you're stuck in that format. But you can transcode between lossless formats like ALAC, FLAC, Monkey's Audio, WavPack or WMA Lossless as many times as you want, so don't worry if a better lossless format comes along. Even the underlying CD format that they are based on--16 bit, 44.1 kHz, stereo, PCM--has been the mainstream delivery format since the 80s.