The MPX-Player for Android

Operating Instructions STUDIO VERSION

Purpose of use

You can use the STUDIO version of 20Tracks to create or edit your own MPX files. For this you need WAV files with the voices of the individual musicians / instruments from your recording software.
Buy and install the STUDIO version in the Google Playstore on your smartphone or tablet. The STUDIO version also includes the PLAYER version. Also read its instructions.

System requirements

If the DEMO or PLAYER version runs smoothly on your smartphone, it will also be fast enough for the STUDIO version. It may take a little longer to complete a new song on poorly performing smartphones.

Creating the WAV files

The more carefully you prepare the export of the WAV files, the less work you will have to do afterwards in 20Tracks. First practice with 1 to 3 voices before venturing into larger projects.

Switch to the STUDIO

Now start the STUDIO version on your smartphone. Either open your own MPX song that you would like to edit or open the empty "NewSong" song to create a new MPX song from WAV files. Then select "CREATE SONG" in the menu. After a few seconds, a list of the voices that were found in the folder opens.

Text color of the voice:

If you click on a voice, a submenu opens:

Sort or switch off voices

If you click on a voice, a submenu opens.

Use the arrow keys to change the order of the voices in the list. Sort the voices according to your needs. A voice marked in red contains an error. You can deactivate it with the trash can symbol and slide it all the way down. As long as voices marked red are active in the list, you cannot finish a song.

Analyze and edit voices

If you click on a voice, a submenu opens.

With the pencil symbol you can edit a voice and explore the detected errors of the voice

The voice page consists of these elements:

Voice name

Here you can give the voice a different name.

Panorama position

Position the voice in the stereo field of the final song.


20Tracks compared the volume of all voices when they were loaded and preset the volume values ​​to match the volume ratios of your recording software. But you can readjust this here. Note that values ​​above + 0dB lead to clipping.

Track information

20Tracks checked the voices for technical problems when they were loaded. If a voice is marked red in the list, you can now determine the reason here. The corresponding line is red here too.

Serious problems (shown in red):
  • The file is not a valid WAV file
  • The bit rate is not allowed (only 16bit and 24bit are allowed)
  • The files have different Hertz frequencies (not allowed)
  • The file is longer or shorter than the other files (not allowed)
  • The WAV file is neither STEREO nor MONO (not allowed)
  • The recording of the file has been overloaded (Max-Peak = 0dB)

More harmless problems (shown in yellow):

  • - - -
  • The files have different bit rates
  • The Hertz frequency is unusual (better to use 22,050, 44,100 or 48,000)
  • The file is slightly longer or shorter than the other files
  • The file is STEREO
  • The recording of the file may have been overloaded (Max-Peak> -3dB)

You can only fix serious problems by reworking in the recording software and exporting this voice again. Or you can deactivate this voice so that it will not be included in the song.

If you have minor problems, you can decide for yourself whether you want to edit the voice in the recording software again or whether you accept the voice as it is. After you have read through the track information of the affected voice, this voice is shown in the voice list as "Everything OK" (white).

Fix track problems

On the Voices page you can set a solution for two problems.

Convert STEREO to MONO

A stereo track is converted to a MONO voice. However, you can decide in advance whether the STEREO TRACK should become two MONO voices with left and right signals. To do this, press the "Split" symbol on the voice page of this voice. You should only remain STEREO signals if there are special effects such as "chorus", rotor effects or the voice clearly moving in the stereo field.

Create common length

You can cut or lengthen a recording that is too short or too long to the exact length of the other voices. To do this, click on the "Cut" symbol on the voice page of this voice. You should be absolutely sure, however, that these were length errors at the end of the recording and not from the beginning of the recording. Otherwise the instruments in the final MPX song will not start at the same time.

Now return to the main page

Song title and additional information

If you click on the song title, the "info page" opens. There you can add further text information to the song:

Song title

This is how the title of the song is displayed (max 20 characters)


This is how the MPX file will be named (max 20 characters)

Composer, band, producer

You can also leave these lines unprocessed (max 20 characters)

additional info text

70 characters of text are freely available here

Now return to the main page

Further settings

in the top right corner you will find a tool symbol. Here you get to the rest of the settings of a song:

Studio ID

MPX songs are encrypted against unauthorized changes with a key. If the creator of an MPX file has given you permission to change its song, you can enter his key here. Only give your STUDIO ID to people whom you want to allow to change your songs.

Noise reduction

Here it is possible to remove background noises from the individual voices before merging them into an MPX song. Attention: Values ​​greater than -60dB can cut the voice itself.

Save as open song

Activate this entry only if you agree that any other user can open your song in his STUDIO version for editing.

Save the song with fade in / out

Adds a soft fade in at the beginning of the song and a soft fade out at the end. Use this option if you don't want to save the complete song.

Song length

Either the entire length of the song is created (check button COMPLETE) or only a part of the song. Enter here start point and length of the MPX-Song. The length must be at least 20 seconds and only a multiple of 2 is possible.

Save and create the song

If you have edited everything, checked and corrected the tracking problems, the button for saving should now be displayed in green on the main page. You can now create the song. This can take several seconds to minutes, depending on the performance of your smartphone.

At the end there is a new song in the list of your 20Track PLAYER. Test the result there and possibly return to the CREATE page for further post-processing. The settings you have made are retained there.

If you are satisfied with the result, open the 20Tracks folder on the smartphone from the PC. You will now find the final MPX file there, which you can now pass on to third parties. Copy this file to your computer, upload the file to a group or publish the file on a homepage.

Before you can start another project, always delete the old folder with the WAV files that is still in the 20Tracks directory. There can only ever be 1 folder in the 20Tracks directory.

Sharing the song

The MPX file is write-protected so that only you can make changes there. This means that third parties can listen to this MPX file but cannot open it with a STUDIO version of 20Tracks. There are several ways you can share the song:

Copy to another mobile phone

The requirement is that the other user has installed a PLAYER version of 20Tracks. Copy the MPX file into the 20tracks directory of another smartphone. There are several ways you can copy a file on another phone. It is only important that the other user moves the file into the 20Tracks directory at the end. There it will be found by the app and can be started.

Transfer the song to a group

This is the most convenient solution for everyone. The requirement is that you have purchased your own group at 20tracks.org. Then you can upload the song there directly from the STUDIO version and third parties can start it there directly with the PLAYER version. Only those who have been given the 8-digit group code are authorized.

Contact us if you are interested.

Transfer the song to your homepage

The requirement is that you have a homepage on which you can create a new directory for these songs. You can then upload your songs there as usual and third parties can download them there directly with the PLAYER version. Only those who have been given the exact URL of the directory are authorized.