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LuxKiller65
04-18-2005, 12:21 PM
Hello everybody, I discovered dBpowerAMP Music Converter some years ago and I'm currently using Release 10.1 ('cause it's the last free version).
I've just begun to read stuff on the Net about converting files to Mp3 and about Lame, and I have few questions on the theme.

/1/ What happens if I convert a joint stereo Mp3 file to a stereo Mp3 file? Will I have true stereo again or is it just like converting from 128 Kbps to 192 Kbps, where I still have 128 Kbps quality sound? And what do I get from stereo to joint stereo?

/2/ What happens when converting a VBR file to a CBR file? Will this make any sense? How do I see if an Mp3 file is CBR or VBR or even ABR? What's the best setting?

If Spoon is right when he says on the guide that "You can't get something from nothing", then going from the "lower" quality setting to the "higher" quality setting is no-brainer, right? But then again, what is the high and the low setting? Joint stereo worse than stereo? CBR better than VBR?

What if I want to go from a 128 Kbps Xing Mp3 file to the exact Mp3 file but encoding using Lame? Useful?

I know it's a lot of questions, but they have been flying in my head through all these years and I'd like not to mess up my files; would be better to know how to cleverly convert and handle original Mp3 files (those gotten from CDs or downloaded from the Net).

Have a nice day dMC community!

neilthecellist
04-18-2005, 03:15 PM
1. No, you will retain 128 kbps sound. Also, converting joint stereo to stereo will do nothing, you'll still have joint stereo sound.

Put it this way ~ If you have say, a lossless file, which is WAV, let's call that a nice green leaf.
When you make something lossy, like mp3, the leaf turns a little yellow. More compression and it becomes a dry brown leaf. Can you turn it back to a green leaf? no.

2. Yes, convert a VBR file to CBR for more OK results.

alrakis
04-18-2005, 03:41 PM
2. Yes, convert a VBR file to CBR for more OK results.

Why? Cannot read VBR? Streaming?
If not one of these, it's totally non sense.

LtData
04-18-2005, 04:03 PM
Actually, converting a song from VBR to CBR is most likely NOT a good idea. Whenever you transcode a song, even if its the same bitrate, you lose quality. Also, converting a joint stereo song to a plain stereo song doesn't make sense to me. Joint stereo gets you the same quality (except at really low bitrates) in a smaller file. I'd say leave your joint stereo and VBR files how they are, unless you have a player that won't play these songs as-is.

neilthecellist
04-18-2005, 08:15 PM
unless you have a player that won't play these songs as-is.
Actually, that's exactly why I said to convert from vbr to cbr. Unless you use Winamp or dAP, you will run into track duration problems with a VBR mp3 file. Trust me, from experience, I know.

LtData
04-18-2005, 08:23 PM
I said a player that won't play it. I think you can forgive a little duration miscalculation unless your burning a CD, then its a little more unforgivable.

neilthecellist
04-18-2005, 08:26 PM
I think you can forgive a little duration miscalculation
A little? Lemme show you a stupid screenshot. brb

neilthecellist
04-18-2005, 08:33 PM
eh....never mind there's no screenshot I can provide. Seems like WMP 10 is ABLE to tell the correct duration of VBR mp3 files.

alrakis
04-18-2005, 08:45 PM
Actually, that's exactly why I said to convert from vbr to cbr. Unless you use Winamp or dAP, you will run into track duration problems with a VBR mp3 file. Trust me, from experience, I know.

I really don't know what a kind of mp3 or player you have Neil...
All my mp3 are VBR: never a problem on xmms, mplayer, kplayer, media player 9, bsplayer, foobar and obviously, as you said, winamp.
By the way I think that suggesting to someone asking you about quality to convert VBR->CBR is a very very bad thing, expecially not explaining the reason (in this case that you've experienced duration problem).

neilthecellist
04-18-2005, 08:48 PM
I don't have an mp3 player. I just have Winamp, and occasionally XMMS on Knoppix Linux when I feel like sticking a boot cd in my computer.....

I don't understand....I SWORE I had problems before with a few VBR files I once created...and now when I went back to play those files with WMP, it shows the correct duration....I'm so confused.

Razgo
04-19-2005, 06:37 AM
2 interesting answers http://www.hydrogenaudio.org/forums/index.php?showtopic=30637&hl=

and http://www.audiograbber.com-us.net/boards/ubb/Forum1/HTML/001538.html

transcoding will always result in loss of quality. whether it makes sense or not depends on why you want to do it in the first place.

LuxKiller65
04-19-2005, 11:26 AM
I see.

But how do I see if an Mp3 file is CBR, VBR or ABR? dMC info tips doesn't show it.

So what's the best setting for using with dMC with Lame? Alt preset standard (for "normal" files, not huge with maxi quality)???

alrakis
04-19-2005, 11:43 AM
It depends on your player: i.e. in winamp you can double-click on the displayed file name or in the menu you can select "view file info".
Also normally in a VBR file you see the displayed bitrate going up and down dynamically, playing the file.
Actually I don't know if there is a way to distinguish ABR from VBR, they in fact are both VBR using different algorithms.
Regarding best setting it's a sort of personal taste and it depends on many factors (music type, where you're goin to listen to, your ears sensitivity).
Generally alt-preset standard is a very good choice, cause it's highly optimized by developers.

alrakis
04-19-2005, 12:46 PM
But how do I see if an Mp3 file is CBR, VBR or ABR? dMC info tips doesn't show it.

??? Are you sure ???
I use dMC 10.1 and it's all there! (except VBR/ABR ok...)
With VBR files it says clearly "Variable Bit Rate Mp3" and the actual average bitrate...
With CBR files it says the actual bitrate...

neilthecellist
04-19-2005, 01:17 PM
same here....and I'm on the registered latest beta for version 11...

and to get file info in Winamp, press alt-3

LuxKiller65
04-19-2005, 01:28 PM
You're all right, I didn't pay attention to that. Thanks!

:D

So it's not worth it if I want to encode a Xing Mp3 file using Lame just because I believe Lame is the prophet of Mp3, right? I would just be getting a worse Mp3 file, right?

New Pope! New Pope! Benedetto XVI, segui le orme del tuo grande predecessore!

LtData
04-19-2005, 01:39 PM
Right. Leave your Xing mp3 files be and just use LAME for your new mp3 files.

LuxKiller65
04-20-2005, 11:20 AM
Ok thanks.
So no way I can encode from Mp3 to Mp3 without losing quality?

neilthecellist
04-20-2005, 11:36 AM
nope.

LuxKiller65
04-20-2005, 12:51 PM
Sad enough. I used to do this every time in the past, with all Mp3 I donwloaded!

But luckily enough it's okay for me to donwload everything again (and again).

:D