# Merging MP3 files into a long file?

**URL:** <https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229>\
**Category:** Factual Questions\
**Created:** [August 20, 2017, 11:33pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229 "2017-08-20T23:33:29Z")\
**Posts on this page:** 19\
**Page:** 1

<div class="post-metadata">

**Author:** ![drad\_dog](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@drad\_dog](https://boards.straightdope.com/u/drad_dog)\
**Post date:** [August 20, 2017, 11:33pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/1 "2017-08-20T23:33:29Z")

</div>

Is this a freeware, or pay thing? I’ve got audacity and it doesn’t look like you can do it there.

This is making one long file from the contents of a digital recorder.

---

<div class="post-metadata">

**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\
**Post date:** [August 20, 2017, 11:44pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/2 "2017-08-20T23:44:10Z")

</div>

I think Handbrake can do it. It’s free.

---

<div class="post-metadata">

**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\
**Post date:** [August 20, 2017, 11:46pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/3 "2017-08-20T23:46:37Z")

</div>

Definitely you can do that in Audacity.  
Import the individual files. They’ll show up in seperate tracks initially.  
Cut and paste the second, third, fourth, etc tracks to the end of the first, in the order you want them.  
Once you’ve cut from tracks, they’ll be empty, without audio, and you can delete them.  
Once all the audio is in the same track, use the export function to turn it back to a single MP3 file.

---

<div class="post-metadata">

**Author:** ![Number](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/number/32/242_2.png) [@Number](https://boards.straightdope.com/u/Number)\
**Post date:** [August 20, 2017, 11:49pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/4 "2017-08-20T23:49:37Z")

</div>

Somewhat surprisingly, you can use the built-in Windows copy command to concatenate mp3 files, e.g.  
**copy /b file1.mp3+file2.mp3 newfile.mp3**

---

<div class="post-metadata">

**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\
**Post date:** [August 20, 2017, 11:53pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/5 "2017-08-20T23:53:44Z")

</div>

> [@Number](#):
>
> Somewhat surprisingly, you can use the built-in Windows copy command to concatenate mp3 files, e.g.  
> **copy /b file1.mp3+file2.mp3 newfile.mp3**

Hmm… will that work if they’re different bitrates? 🙂 I suppose I could experiment.

---

<div class="post-metadata">

**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\
**Post date:** [August 20, 2017, 11:53pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/6 "2017-08-20T23:53:57Z")

</div>

To do it properly, read [this](http://lyncd.com/2011/03/lossless-combine-mp3s/) (uses mp3cat) or download [this](http://www.shchuka.com/software/mergemp3/) if you run Windows.

---

<div class="post-metadata">

**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\
**Post date:** [August 21, 2017, 12:05am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/7 "2017-08-21T00:05:11Z")

</div>

> [@chrisk](#):
>
> Hmm… will that work if they’re different bitrates? 🙂 I suppose I could experiment.

I tried with a VBR and 160 mps CBR mp3… surprisingly windows media player actually played both, although the progress bar only showed the first song.

And I still think Audacity is a good tool to “properly” do this with. 😉

---

<div class="post-metadata">

**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\
**Post date:** [August 21, 2017, 12:13am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/8 "2017-08-21T00:13:23Z")

</div>

You can do it in Audacity, [but:](http://wiki.audacityteam.org/wiki/MP3)

> [@](#):
>
> Every time you export from Audacity as an MP3 (or other lossy audio format), this encoding necessarily degrades some of the original quality of the audio. If you import an MP3 into Audacity, edit it then export it as an MP3, you are thus losing quality **twice** - once in the original MP3 encoding of the imported audio, then again when you export it from Audacity as MP3.

---

<div class="post-metadata">

**Author:** ![JKilez](https://avatars.discourse-cdn.com/v4/letter/j/e5b9ba/32.png) [@JKilez](https://boards.straightdope.com/u/JKilez)\
**Post date:** [August 21, 2017, 1:23am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/9 "2017-08-21T01:23:45Z")

</div>

> [@DPRK](#):
>
> You can do it in Audacity, [but:](http://wiki.audacityteam.org/wiki/MP3)

That is true, but in experiments I did many years ago I found that 99% of the audio degradation to high bitrate mp3 files is done with the first encode (where it first applies the steep low-pass filter). Subsequent re-encodes suffer very little degradation. It is not like audio tape, where every generation adds the same amount of noise.

---

<div class="post-metadata">

**Author:** ![drad\_dog](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@drad\_dog](https://boards.straightdope.com/u/drad_dog)\
**Post date:** [August 21, 2017, 2:11am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/10 "2017-08-21T02:11:37Z")

</div>

> [@chrisk](#):
>
> I tried with a VBR and 160 mps CBR mp3… surprisingly windows media player actually played both, although the progress bar only showed the first song.
> 
> And I still think Audacity is a good tool to “properly” do this with. 😉

What menu/command sequence would do that?

---

<div class="post-metadata">

**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\
**Post date:** [August 21, 2017, 2:26am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/11 "2017-08-21T02:26:30Z")

</div>

> [@drad\_dog](#):
>
> What menu/command sequence would do that?

For Audacity?  
[ol]  
[li]File \> Import \> Audio…[/li][li]Edit \> Cut[/li][li]Edit \> Paste[/li][li](Repeat 2 and 3 for each MP3 to merge beyond the second)[/li][li]File \> Export Audio…[/li][/ol]

---

<div class="post-metadata">

**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\
**Post date:** [August 21, 2017, 2:42am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/12 "2017-08-21T02:42:44Z")

</div>

If I remember correctly (and I may not be), you don’t have to cut and paste in Audacity. Just import all of the files, slide them along so that they are sequential one after the other, then select all and export as wav or mp3 or whatever you want your final destination file to be.

---

<div class="post-metadata">

**Author:** ![drad\_dog](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@drad\_dog](https://boards.straightdope.com/u/drad_dog)\
**Post date:** [August 21, 2017, 4:20am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/13 "2017-08-21T04:20:32Z")

</div>

> [@chrisk](#):
>
> For Audacity?  
> [ol]  
> [li]File \> Import \> Audio…[/li][li]Edit \> Cut[/li][li]Edit \> Paste[/li][li](Repeat 2 and 3 for each MP3 to merge beyond the second)[/li][li]File \> Export Audio…[/li][/ol]

You mean 2 keystrokes for each file? There’s 125 files.

---

<div class="post-metadata">

**Author:** ![TwoCarrotSnowman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/twocarrotsnowman/32/15879_2.png) [@TwoCarrotSnowman](https://boards.straightdope.com/u/TwoCarrotSnowman)\
**Post date:** [August 21, 2017, 7:42pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/14 "2017-08-21T19:42:55Z")

</div>

I haven’t used Audacity for a while, but I think it supports batch commands.

Failing that, if you don’t mind a learning curve, there’s an audio application called REAPER which has a free trial, and allows very sophisticated batch processing.

Sent from my SM-G935F using Tapatalk

---

<div class="post-metadata">

**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\
**Post date:** [August 21, 2017, 8:51pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/15 "2017-08-21T20:51:20Z")

</div>

If you use the Merge MP3 freeware I suggested, you can either select an entire folder full of mp3 files to merge, or click on “Add files” and bulk select files using the keyboard or mouse. Having hundreds or thousands of files on the list is no problem.

---

<div class="post-metadata">

**Author:** ![drad\_dog](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@drad\_dog](https://boards.straightdope.com/u/drad_dog)\
**Post date:** [August 22, 2017, 2:13am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/16 "2017-08-22T02:13:39Z")

</div>

> [@DPRK](#):
>
> If you use the Merge MP3 freeware I suggested, you can either select an entire folder full of mp3 files to merge, or click on “Add files” and bulk select files using the keyboard or mouse. Having hundreds or thousands of files on the list is no problem.

I tried Goldwave on it and it worked. I found it very hard to fathom audacity containing dozens of files and didn’t seem to read what I wanted to do.

---

<div class="post-metadata">

**Author:** ![erysichthon](https://avatars.discourse-cdn.com/v4/letter/e/d07c76/32.png) [@erysichthon](https://boards.straightdope.com/u/erysichthon)\
**Post date:** [August 22, 2017, 2:25am UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/17 "2017-08-22T02:25:41Z")

</div>

> [@DPRK](#):
>
> If you use the Merge MP3 freeware I suggested, you can either select an entire folder full of mp3 files to merge, or click on “Add files” and bulk select files using the keyboard or mouse. Having hundreds or thousands of files on the list is no problem.

I second Merge MP3. It will concatenate MP3 files with no quality loss.

Audacity is a great program, but I don’t recommend using it for this purpose because it will re-encode the file (resulting in loss of quality) when you save it.

---

<div class="post-metadata">

**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\
**Post date:** [August 22, 2017, 9:40pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/18 "2017-08-22T21:40:30Z")

</div>

I have an old version of Roxio Recordnow (9) where I can drag and drop additional files into an open project, then join the clips.

---

<div class="post-metadata">

**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\
**Post date:** [August 23, 2017, 9:07pm UTC](https://boards.straightdope.com/t/merging-mp3-files-into-a-long-file/794229/19 "2017-08-23T21:07:25Z")

</div>

> [@erysichthon](#):
>
> I second Merge MP3. It will concatenate MP3 files with no quality loss.
> 
> Audacity is a great program, but I don’t recommend using it for this purpose because it will re-encode the file (resulting in loss of quality) when you save it.

Audacity does have one difference: you can manually “smooth” over the junction between songs (i.e. eliminate either noise or silence that would indicate where the splice point is). I’ve gotten pretty good at doing so.
