ALAC & M4a, same thing?

[Twill]

Hi,

I have a quick file format question.

Having recently entered the iRealm, I was thinking about converting my FLAC library to ALAC so that it will play nicely with my Apple-side.

As far as I am aware, the file type for apple lossless is .ALAC. But I just did a trial conversion of 1 FLAC file to ALAC, and it shows up on my QNAP QMobile app as an M4a file. What's the difference between M4a and ALAC? Is ALAC a varient of M4a, or is my QMobile app getting confused?

I only ask because I'm looking for a streamer to stream from my NAS, like the Marantz MCR603 or Denon Ceol, and I'm trying to ensure file compatibility as far as possible.

Some devices list M4a as a compatible file format for network streaming, but I'm struggling to find one that lists ALAC.

Cheers. Again. One day I'll stop posting questions and start posting answers!

 

[Twill]

Slightly answered my own question with A quick Google.

M4a is a container format that carries both AAC and ALAC variations.

What's still not clear is whether a streaming unit claiming M4a format compatibility can play both the compressed & uncompressed variation, or just AAC.

Anyone know if the MCR603, for example, plays ALAC specifically?

I've asked Marantz and they just pointed me at the manual, which says M4a.

 

[Anonymous]

ALAC is a codec, which, as you say, must be wrapped up in a container, ie m4a. If a streamer or DAC supports m4a, the file will play as long as your DAC supports the sampling frequency and bit depth, ie 24 bit 96 khz etc etc. I can't find a Windows based converter that will change a high bit rate FLAC into an ALAC. iTunes of course will not play FLACS, and never will. FLACs are a thorn in Apple's side. I have found a converter though that will convert high bit rate FLACs to AIFF files which iTunes supports. Will only convert to a maximum 96 khz sampling rate though, so a 192 khz file will be halved in size. I'm not sure that any human ear will ever be able to hear a difference mind. The program is called 'AIFF MP3 Converter' and costs about £15.

Pete