File formats - Why we use what we use!

[Bobby Watson]

I am using version 3.9.9.0 of the codec and it will convert 24bit..
I seem to remember some time last year, that we had a situation in my studio where folks all of a sudden were having problems opening ape files. What happened, is one of us had installed a new version of MA, without knowing it was new. And, there was some incompatibility with the old version results....

If you have been using it for a long time I'd suggest you update, and pass the word...
BW@

[Letizia]

Mp3's will alter the audio  (it is not lossless).  I would like to dig into the issue of "dead space" and all a little more though.  I haven't seen the problem myself so I wonder if its due to a specific codec?  I use lame.exe (v3.93, command line version, http://lame.sourceforge.net/).  what is everyone else using?

interesting... you may be on to something. is your OS Windows? i've been using the codec that came with the multitrack software and it adds the 127ms or so. think i'll try the Lame codec.

fwiw, the space isn't noticeable unless you zoom way in, but being a drummer you'd likely hear it. course it'll only cause trouble if your sending out an mp3 for others to track to and subsequently loading their new tracks into your original project. if you're only adding tracks to someone else's bed, then it's not an issue.

would you mind converting a small wav to mp3 and then posting the mp3? here's the wav:

http://www.letiziamusic.com/audio/test18Mar2006letizia.WAV

[spacecube]

Hi  !
one question...maybe there's an answer somewhere in all threads but don't have the time to browse !

about this comment and uploaded files.
"Uncheck the attachments you no longer want attached"

Does this mean that the file I have uploaded is completely deleted from the server if I uncheck it when modifying my post ?
Or is there another way to delete an uploaded file.....
okay there's an option to delete but does'nt that mean that I delete the whole post if I click at that option ?

thanks
SpaceCube

[NickT]

Juhani,

about this comment and uploaded files.
"Uncheck the attachments you no longer want attached"

Does this mean that the file I have uploaded is completely deleted from the server if I uncheck it when modifying my post ?
Or is there another way to delete an uploaded file.....
okay there's an option to delete but does'nt that mean that I delete the whole post if I click at that option ?

That is correct...If you want to save the post but not the file...just un-attach the file..it will delete from the server and make room.

Nick

[spacecube]

Thank you Nick ! 

[NickT]

I can ape and un-ape to the same thing all the time...just tested.

If you select Wave

Bits as source
Feq as Source
Channels as source

It will uncompress to the original file. Now if someone aped to 16...it will open to 16. So you have to be careful as to what you ape to. 24 to 24...and so on.
Nick

PS...Learjeff told me about that!

[Sharpola]

+1   24/48 no prob..

Ray

[digitaldrummer]

would you mind converting a small wav to mp3 and then posting the mp3? here's the wav:

http://www.letiziamusic.com/audio/test18Mar2006letizia.WAV

tried to download it, but getting a 404 error--maybe you took the file down already?

Mike

[Letizia]

sorry bout that Mike. recently changed servers... file got overlooked in the shuffle.

it's there now

http://www.letiziamusic.com/audio/test18Mar2006letizia.WAV

thanks

[digitaldrummer]

Ok, here's a 192Kbps mp3 made with lame 3.93 (not the most current build but works for me).

Mike

[Letizia]

thanks Mike. turns out your conversion adds approximately 51ms of space to the beginning of the file. fwiw, it also adds around 25ms of space to the end of the file. btw, are you on a Windows pc?

i'd like to get one of the Mac guys to convert the same Wav file to mp3. any takers? Gerk?

http://www.letiziamusic.com/audio/test18Mar2006letizia.WAV

[Gerk]

Yep glad to try this out.  This has long been puzzling me too.  I can try a couple of different methods to MP3 it as well and we'll see what happens.

Mark

[Gerk]

Here it is encoded with a (slightly older) version of LAME on latest OSX.

Mark

[Gerk]

My tests show, for 2 different versions of LAME that they both did indeed add time to the file. 

WAV: 0:14:86 seconds
MP3: 0:14:94 seconds

So not the same amount of time added as with Mike's version of LAME.  I want to dig into this some as well. 

For the sake of information, I tried 2 different methods for making the MP3.  One was with a project called LameBrain (OSX LAME front end, very nice actually), using LAME version 3.95

The second I did from Digital Performer (my DAW software) using the LAME framework (osx system level addon).  It seems older ... doesn't include version information with it, but the header (lame.h) seems to be from Dec 2003.

Mark

[Gerk]

ok, just found the answers for this one.  This is apparently expected behaviour of ALL the MP3 encoders and decoders out there from what I've just read.  It also explains some of the timing differences between Mike's and my mp3 tests (older versions of LAME added more padding).

It's a bit technical, but check it all out here:

http://lame.sourceforge.net/tech-FAQ.txt

Sadly I don't think there would be any sort of easy fix to any of this.  This extra space is needed for several reasons (explained in that faq).  Also with different versions of LAME, and with different encoders/decoders the appended and prepended samples can't be properly predicted, so there's no real way of "fixing" something like this.  Also with different bitrates and encoding options the amount of padding required can change as well.

Now after all these explanations, it really makes me wonder if WMA doesn't also pad both ends of a file... it almost seems like for a compressed format it would be required.

Anyone wanna test this?   I can't really encode wma on OSX properly.

Mark