Need a DJ for your run?

Just a quick heads up on a running dj app for those who own Android phones.

It sounds very interesting. It can detect the BPM of songs on your phone, and then while you're working out it detects your SPM using the phone's accelerometers (the same way a pedometer app works). Then it plays the songs whose BPM match your current SPM.  I have an iPhone so can't test this, but I have been seriously thinking of getting an Android phone and if I do I'll definitely have a closer look. The reviews look quite mixed, either it works and people love it or it just doesn't work at all. Just one final thought, in a way its doing things the wrong way round, its matching music to the SPM when what I want use music to help me keep SPM in a target range. Still I am very interested and think anything that takes SPM this seriously is worth some attention!

Take Control of the BPM

Today's post is a long one, but I really hope that it is useful to you.  I am going to show you how to take a song and change it's BPM.  The first time you do this it will feel like a lot of work, but after you have installed the right tools and know how to do this, it only takes a minute or two to change the BPM of a song and you will be master of your running playlist. But you have to promise to still read my blog!

First off I am going to assume you have read my blog post, Intro to BMP, and already have MixMeister BPM Analyzer installed.

So lets say you have a song that you feel just makes you want to run, an anthem to your self expression through running, but it just isn't the right BPM. For me Galvanize by The Chemical Brother is this song and I was well inspired by this video featuring some italian Vibram FiveFingers wearers.

Using our half, or 90 BPM, works as good as 180, it is way to fast at 104 BPM. So in this post I am going to show you how to use a super and free tool called Audacity to slow down the BPM to 90.

Click here to go to Audacity's home page. Right in the middle of the page you should see the download links.

I clicked on the first link, since I have Windows, and I don't have the newest version of Audacity, the 2.0.0, which was released 13.03.2012. Once you've downloaded the file, double click on it to install Audacity. I then clicked yes to everything without reading anything, like any other normal software user. Just so you see the irony here I am a software developer who once spend several months designing an installer for our software...

The installer will automatically launch Audacity for you, so you should see a window like this.

Now grab the audio file containing the track you want to change. I have my music in mp3s, but Audacity can handle other formats, check here to see if you're covered.  So to load my file I go to the File menu and select Open, then browse to the folder containing my file.

Then go to the Effect menu and select Change Tempo.  This will open up the following dialog box.

In the Beats per minute: Textboxes type in the from and to BPM.  For me its 107 and 90. Audacity automatically fills in the percent change.

Then hit OK.  Finally you have to export the song into a new file. Go to the File menu and select Export... you will be prompted to choose a file name and location.  Don't choose the same file name and location or you'll write over the original. You will then have a chance to edit the meta data, I just click OK on this dialog.

If you choose to save it as an mp3 you will get this dialog.  Don't worry this only happens the first time.

Audacity, due to patent constrictions is not allowed to ship this dll (a software file that provides some functions), so you have to install it.  The Audacity wiki has a page, here, to explain how to do this. -  in fact you'll get taken to that page, to the right section even (they detect your OS), if you click on the Download button.  If you are a Windows user here's the essential info (copied from the Audacity wiki page)

1. Download an unzipped copy of the required lame_enc.dll here
    Left-click this link, do not right-click
2. Do not open this file, but save it to your computer. As you will be using this .dll file directly for encoding it is recommended to save it into your Audacity installation folder. This is normally at C:\Program Files\Audacity. For me it is C:\Program Files (x86)\Audacity.  

Just to be sure this worked I ran the new file through MixMeister BPM Analyzer.  And well it says my file is 87.48 BPM.  That's fine, in range, but I tried again, using Audacity, going for a target 92 and also 93 BPM. The 92 ended up at 89.42 and the 93 at 90.39.  I choose the 90.39 version, since it changed the original song by a lesser amount.  Don't ask me why this didn't work exactly, I think that the BPM detection isn't perfect.  It's always a good idea to double check the BPM using a tap for BPM tool.  I have done this for over a hundred songs and usual it works the first time, and its only occasionally that I have to tweak a song like this.  Anyway if you are curious to hear what the result sounds like here's a short sample.

One final thing to discuss is the ranges of BPM that can be changed. If I have a song that is 130 BPM or above I up it to 180.  Some songs sound too fast, but most, and pretty much everything over 150, sounds good.  Going down is harder, I usually put the limit at 100, but made an exception here at 104. Stuff less than 90, well I usually try taking songs over 70 to 90. You may notice that a lot of songs are in the 110 to 130 range, which is a great BPM to dance to, but usually don't sound good after tempo changes.  Still I was able to create a running playlist with almost all my favourite songs using Audacity.  I hope you can now too.

Intro to BPM

So for my first real post I am not going to even recommend a song I am going to tell you how to figure out the BPM of your music library. You probably have songs that are the right BPM that you love already. What you need to do is figure out the BPM of all your songs.

I did this using MixMeister BPM Analyzer, which you can download here. Don't forget to unselect the "Would you like to hear about..." check box, if you don't want to get spammed.

They have a Mac and PC version. I am assuming you Linux guys will know how to find a BPM analyzer all by yourselves.

Unzip the downloaded file and run the .exe file, which will install MixMeister on your machine and launch the programme. You can add your music by clicking on the first little folder icon on the top bar and choosing a folder to be searched for music. So add either just an album or your whole music folder.

MixMeister calculates the BPM and writes it to the files ID3 tags, which can be read by other music programmes like iTunes. Note : MixMeister works with mp3s. If you have your music in another format and want to convert it, you can use iTunes and follow the instructions on this page.

That was quite a bit of work, and depending on how much music you have probably took a while. So now have a look, do you have any 180BPM songs? The chances are you don't! A lot of music, maybe even most depending on your taste falls into the danceable 100-130BPM range. The good news is that songs with a BPM of 90 work just as well. 90 is half of 180, and in fact I can't figure out the difference in sound from 90 to 180BPM. So hopefully you do have a few songs at 90BPM, you can also try 89 or 91. It doesn't have to be super precise.

Happy Running!