hearandknow

Archive for January, 2012|Monthly archive page

Tempo and beat detection with Ableton Live

In ableton, daw on January 17, 2012 at 01:19

Sometime it is difficult to detect the tempo and beats of an audio file. This is a short tutorial how to do this with Ableton Live.

First of all listen to the example. It’s the vocal Ghosts Of Lees sang by Kaer Trouz from ccmixter.org. In my opinion it’s not so easy to hear the beat in this piece of music.

Our great advantage is that western pop music is written in a 4/4 rhythm and the global tempo doesn’t vary. Otherwise this job is much more complex, but this did not happen in this case.

Let’s walk through the step I suggest.

  • Load the file into a clip slot for audio files. By the way the initial tempo of your song doesn’t matter, because you will change it later.
  • If you look at the sample display, you can will recognize some returning patterns. We are very fortunate that the length of each pattern is equal.

  • Enable the warping and set a warp marking at the end of the first pattern we had recognized.

  • Listen again to the first pattern and guess the number of beats. Maybe you like to clap or count to the music. In this case I think eight beats will work. In order to adjust the tempo move the warp marker to the marker for the ninth beat. If you take a look at the Segment BPM value, you will find the tempo calculated by Ableton Live. In that case it is 89.56 bpm.

  • Now we set Ableton’s tempo to this calculated tempo and remove the warp marker created by you. You may note that the display behind the deleted warp marker will update. This is why the rest of the audio gets the new tempo.
  • If you take a look at the sample display you can see that the transients fit very well to the beat.

    And here is the result with the metronome.

    That’s all. I shall not hide the fact that the second part of this example has an error. You have to manipulate the audio to fix this, but this is not our job today.

    I hope this quick tutorial will help you. Best regards.

    alexander

Create your own ambient & drone sounds

In audio effect, software on January 7, 2012 at 19:08

I few weeks ago I found a open source software called Paul Stretch. This application is build for extrem time stretching of music. Before I take a closer look, I will give you the download URL for many operating systems: Sourceforge.net/paulstretch/

The worst first, the GUI is not very nice, but there are very good smoothing algorithms implemented, so audio could by extremly time stretched without any unwanted artifacts. This tool helps you to create sound you know from drone or ambient music.

First of all here are some screenshots. As you can see there is the option to adjust many parameters.

Here are two examples I made. The first one is generated from a short vocal sample ..

.. and the second one is from a drum loop.

Many thanks to Nasca Octavian Paul!

Your Alexander