Audacity Forum

Hi Everyone:

I am trying to put the content of several music CD's into one so that I would only carry one CD with me to the car and listen to all my songs (the quality of the MP3 is good enough for the car stereo). As a result, I have all my tracks in MP3 format. Some of them were actually purchased from online as MP3 and others were ripped from the actual CD album. Now, the problem that I have is that on the original CD, some of the songs are continuous without any gaps. So, the player switches seamlessly from one track to the next (for example Pink Floyd Dark side of the Moon). However, when I create my files using MP3, there is a small gap (about 0.5 seconds) between the tracks, and I do not get the seamless jump from one track to the next. I used Audacity, and I cleaned the file, by removing the extra 0.5 seconds of silence from the MP3 file. However, upon recreating the MP3 (from the cleaned and cut version), once again I get the 0.5 seconds (or so) in the file, and again the jump from one track to the next is not seamless. Once the files are created properly, I plan to burn them a CD using Nero 8 Express Essential (Disc at once) or any other suggested burner.

After doing lots of research online, I have not come up with any solution, and I was hoping someone here would be able to help. Two things that I have found are as follows:

1- Instead of using LAME decoder use Blade codec. Would this work and would I be able to use it with Audacity?

2- Create one long WAV file with all the tracks joined into a single file. Then convert the long WAV file into MP3. The problem here is that the WAV file is huge, so it has to be converted into MP3 (because of my initial intent explained earlier). Also, if I do this, is there anyway that I can tell my car stereo (by using CUE files, etc) where each track is so that I can skip or go back to different tracks?

3- Use MP3DirectCut to cut the silence (0.5 seconds) from the end and beginning of the tracks. The problem with this is that the Audio level is approximate and I am not sure if cutting the information is only cutting the silence and not the actual data.

Options 1 and 2 seem more logical if they work. I would appreciate all the detail help you can give me. Thanks you.

This problem is a limitation of the MP3 format.

Encoder/decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback.

http://en.wikipedia.org/wiki/MP3#Design_limitations

booboo_US wrote:1- Instead of using LAME decoder use Blade codec. Would this work and would I be able to use it with Audacity?

It is possible to use Blade encoder with Audacity, but it's fiddly to set up, the encoding quality probably not so good (Blade is quite old now) and it would not solve the problem. The problem is with MP3 format specification, not with LAME.

booboo_US wrote:2- Create one long WAV file with all the tracks joined into a single file. Then convert the long WAV file into MP3.

Yes that should work.

booboo_US wrote: if I do this, is there anyway that I can tell my car stereo (by using CUE files, etc) where each track is so that I can skip or go back to different tracks?

Probably not.

booboo_US wrote:3- Use MP3DirectCut to cut the silence (0.5 seconds) from the end and beginning of the tracks.

No, that won't work either. There will still be a bit of silence at the split.


Some MP3 players are able to compensate for the silence if they are playing tracks from a play list. If your car player has this feature you will need to:
1) Encode the MP3 with "gap information" embedded (
2) Add a play list to the CD
3) Enable "gapless MP3 playback" on the player
4) Play the playlist rather than playing the MP3s directly.
See here for more information: http://wiki.hydrogenaudio.org/index.php?title=Gapless


Another possible option is that if your player supports OGG files, the OGG format does not suffer from this limitation.

Failing that, I'd go with "2- Create one long file", at least for those tracks that need to be gapless.

Thank you Steve. I did use Blade encoder and that did not work. Also, I still have not played with MP3DirectCut, but I tend to agree with you that this option will not work either.

Since this afternoon, I have also used foobar 2000 to write a gapless CD. This did a much better option, and the tracks are almost seamless, except a click as the music goes from one track to the next. Most likely this is because of the silence in the MP3 files.

I can't believe that such a simple thing (at least to an end user) is so complex and does not have a good solution. I will try the OGG tomorrow, and will see if that works. As your other options of just keeping the long WAV file, that is not such a good alternative because Most of my CD is from a live show, and I like some songs more than others. So, sometimes I want to listen to all the songs, other times, I want to skip the ones that are not my favorite and more on. So this option takes away this flexibility.

Any other suggestions and solutions are greatly appreciated.

Thank you Steve. After trying everything that I could for two days, I came to the conclusion that even though the task seems relatively easy, the feature that I am looking at is not possible. I don't know how many CD's I have burned to test everything that I could think of and all the suggestions that I have received.

My car stereo only plays MP3 and regular CDA files. CDA is good and the tracks play continuously gapless, but each CD can only be 80 minutes. So compacting several CD's into one would not work. For a while I thought that Foobar has a trick to fit more than 80 minutes on a CD, but I was wrong.

On the other hand, MP3 is good in the sense that I can fit many albums on a single CD, but it is horrible for gapless music such as live music. As the song goes from one track to the next, the player has to read the new file, and there is a rather long pause. So there is no flow.

I am just amazed that with the technology that we have, this simple task cannot be done. Oh well! Finally, I have decided rather than burn CD's, to put all the files on my iphone and go in that direction by hooking it up to my car's stereo. Of course, I have not tried this yet, but from what I read on the web, itunes should produce gapless music. So, hopefully this will work. I would like to thank you for all your help and suggestions. I guess I will close this thread

Thank you for your thorough and concise summary booboo_US, I think that you have summed up the issues very well.
I'll lock this topic now and mark it as "closed" as I think that your summary can be a useful reference the next time this issue comes up.

Just to add a couple of points before closing.

Although technology has moved on rapidly, the MP3 format is old. The benefit of its age is that it is very widely supported by both software and hardware players. Unfortunately it is not open source and is bound by multiple patents in many countries which has stifled development (and is the reason that Audacity does not include MP3 export as standard).

Ogg Vorbis is a more modern format and does not suffer from the problem of adding silence to the beginning of the track. The sound quality of Ogg is as good if not better than MP3 and it is free of patent restrictions. Sadly it is not so widely supported as MP3.

Standard audio CDs have a gap between tracks, typically 2 seconds, and use uncompressed PCM audio data. Gapless audio CDs are possible if (a) the CD burning software supports it, (b) the CD burning hardware (drive) supports DAO (disk at once) mode.

MP3 CDs are not standard audio CDs and will not play in many standard CD players. Some CD players (and most computers) support playing MP3 disks. An MP3 disk is just a data CD with MP3s on it.

Some MP3 players are able to play MP3s and compensate for the gaps so as to provide gapless playback. This is primarily an issue for the player as the MP3 format itself does not allow for gapless playback. How to achieve gapless playback may not be straightforward, it depends on the player.

MP3 is a lossy compression format. The sound quality is never quite as good as the uncompressed original, though it may be extremely close if high bit rates are used. Each time that a track is compressed to MP3, some of the audio information is irretrievably lost, causing a loss of quality. The same is true of other lossy compression formats, including Ogg, WMA, AC3 ....