Mixed In Key Review - Part 1

Mixed in Key - Pete Tong

Pete Tong endorses Mixed in Key; as a DJ tool it is definitely worth at least considering it for improving your sets.

Mixing in key is something that lots of DJs vaguely know they ought to have a go at. Top DJs mention mixing in key, and many commercial mix CDs use key mixing. In some scenes, like trance, where the melodic content of music is really important, mixing in key is quite widely accepted; and for all DJs, it can make your mixes smoother and more professional-sounding.

Nonetheless, for most mixing in key with software like Mixed in Key remains somewhere between a mystery and an ideal. While some DJs come from a musical background, many don't, and for those, any tool that can help them do it must be worth investigating.

This is more than just a review of Mixed in Key (US$58, and now up to Mixed in Key 5.5); it explains the topic first, introduces the software and finally, in the Mixed in Key Review - Part 2, shows what happened when I tried to DJ a whole night at a real gig, only mixing in key.

Should DJs bother about mixing in key at all?
I have mixed thoughts about this technique, which I first wrote about in Should Digital DJs Be Bothered About Mixing in Key?. In that article I also stated that I hadn't actually tried it other than by trial and error, and that I would one day try key mixing software and report back.

Well, thanks to a productive chat with the Mixed in Key people, I now have a review copy of that company's software (you can pay for a Mixed in Key download via their website); software that aims to bring this technique from an ideal to something practical that DJs can actually use in their sets.

So, with the software loaded onto my Macbook Pro, I am ready to put it through its paces. As I write, I am also preparing for a gig this evening, where I intend to actually use the software to only mix in key. So in Part 2 of this review, I'll bring you my thoughts and experiences after a real gig using it, and answer my previous question from the first article as to whether DJs should be bothering with this stuff at all.

Still not sure what mixing in key is all about? No problem! Let's review some basics:

What is a musical key?
All music is in a key. If you hum a tune, you choose which note to start on. It's the same tune whether you hum/sing it high or low. By starting on a different note, you're singing the song in a different key. (Many singers have a preferred "key" that they like to sing in, even though they may not consciously know it.)

Another example: Even seen a guitar player with a capo on his guitar? (That is the thing across all six strings that makes the whole guitar sound higher even though the player is playing it exactly the same as normal.) That's a way of changing the key of a song too.

Have you got a "key lock" button on your DJing software or DJ controller? (That is the button that when pressed, means when you speed up or slow down the song, it doesn't get and higher or lower in pitch.) If that button is switched off, the key changes as you alter the pitch.

Are you beginning to see what "key" means in music now? Really, it's nothing complicated. (Although when you get into it there are of course formulas, musical scales and relationships, that prove that music and maths are definitely linked!)

Making all of this accessible to DJs
The challenge has been to find a way to use musical key information productively as a DJ. Previously, to do so you had to have some kind of musical theory training to understand how keys and scales fit together. It is hard for the majority of non-musically trained DJs to get their heads around all of this, and that's where Mixed in Key enters the game.

Mixed in Key is a piece of software that processes your music, adding a tag for you to access information about the key that music is recorded in. It then offers you a relatively easy way of using that information to mix tunes together in your DJ sets either of the same or related keys, which will make your mixes sound better. In shot, it tells you what will mix into what, key-wise.

Mixed in Key review - opening screen

Mixed in Key is a simple enough program to use, with only a few screens and options.

Why is mixing in key important?
If you just throw any tunes together, the keys will more than likely clash. Think of a bad choir! The reason is that not just any old notes go well together. But if one song is in the same key as the next, or if it is in a related key, the tunes will mix just fine. That means that as a DJ, you can do more adventurous mixing:

  • You no longer have to wait until one song is just the drum part before bringing in a musical part of another song
  • You can drop acapellas over instrumental background tracks
  • You can switch between songs of different keys knowing things will sound OK, as you'll be able to know when the keys are related
  • You know when you can't mix two songs together musically so you can adjust the type of miix you are going to do accordingly
  • You can use advanced techniques, like moving "up" on every mix, to build tension (a trance DJ favourite)

It's something I've, as I say, only done through trial and error in the past (when I find two tunes that are in key with each other I add "mixes in key with..." information to my comment tags to remind me), but with Mixed In Key, it is now claimed to be possible to do it systematically. Let's look:

Installing the software
The software is paid for and downloaded online from the Mixed in Key website.

Installation is straightforward, and once you open and add your registration key, you're shown a simple window that you can add songs to for analysis.

Mixed in Key Demo - processed

Once your songs are processed, the software tells you - but as long as you set the preferences correctly, it has also added the information to your ID3 tags for viewing in your DJ software.

Preparing to analyse your files
You're going to have to think about where you ask Mixed in Key to save the key information it finds; if you're really old school and you still sort and review your songs by filename information, it can write it to the filenames, but if not, you can choose to have it written into the custom "Initial key" ID3 tag (for Traktor users) or added to the Comment tag (a pretty universal method, and as it can add it at the beginning of that tag, you can then sort by that field in your DJ software to easily get songs in the same or similar keys together). The basic premise here is to get the software to display the key information in your DJ software; otherwise, there's not much point having it.

You're also probably going to do some housekeeping with your ID3 tags, checking they're modern ID3 2.3 - some older MP3s might have ID3 tags in an earlier format. iTunes can convert all your ID3 tags to 2.3 for you, but beware - it will take its time. I have a current set list, so for this experiment I've told iTunes to convert my ID3 tags to 2.3 only for that list, just to be sure. (You right-click on any selected bunch of files and select "Convert ID3 tags".)

Analysing your music
When you're ready, you can either add files or folders, or just drag your playlists from iTunes to the Mixed in Key window (that's what I did - dragged my current set). The software then takes a few seconds to process each tune, working out the key information in a special system (more later). This means that it will take a long time for a large collection, of course.

It's also worth taking note that the software apparently "accesses complex algorithms" online, so you need to be connected to the internet for it to work. Whether this is strictly true or whether they use this to stop piracy I'm not sure - anyway, that's the way it is. No biggie unless you want to analyse tunes on the fly while you're at a gig and have no wireless - I guess this may irk a few people, but I'm happy enough with it.

Look at the screenshot of the Mixed in Key software above. Notice the column with lots of "Key" values in it? That's your key information. (You'll also notice that some of the songs are hyperlinks. That's for another piece of music processing software called Platinum Notes, from the Mixed in Key people. I'll cover that at a later date.)

So, now we have the key information accessible to our DJing program. How do we make use of it?

The Camelot System
Here's the theory: these numbers and letters are part of the Camelot notation, most famously represented with the Camelot wheel. See the key names (D major, F minor etc.) below? They're the traditional names for musical keys. The adjacent numbers and letter represent the Camelot wheel's version of them.

You don't actually need to have a copy of this wheel, though, because the premise is really easy: when mixing two tunes, you can go up or down a number while keeping the letter the same, or go from A to B (or back) while keeping the number the same.

mixed in key review - camelot wheel

The Camelot wheel matches traditional key notation with its own special version for DJs.

What the letters and numbers mean
Bear with this theory for a second, as once you get to grips with it you'll understand what you're actualy doing when you're mixing in key with this notation a little better.

Do you know the difference between a major and a minor key? If not, suffice to say one sounds "happy" and the other moodier. (Once you've analysed your songs, you can listen to them and hear the difference I'm talking about.) In the Camelot notation, the keys with "A" at the end of their key are in major keys, and those with "B" are in minor keys.

There are 12 notes in a Western musical scale, and so 12 possible keys, each with a major and a minor variant. Hence the 12 numbers.

The reason you can go from 11A to 12A or 5B to 4B (for instance), is that for every key, there are two related keys you can mix well into, and the Camelot wheel is set up so that those keys are one number more or one number less than the current key. That's why when DJing, if you want your mixes to sound great, you simply do as suggested - go from A to B or back again, or up or down a number - or, of course, stay on exactly the same number/letter combination.

See now how this could be a great way of making your DJ sets sound better without really knowing too much about the science behind it all?

mixed in key review - dubfire

Dubfire uses this software, and like many DJ/producers, he says the reason is that he doesn't have to use a keyboard to determine the key of a track any more.

Remember the tempo!
One crucial thing to remember is that the tracks are in the keys that Mixed in Key says they're in only when at 0 pitch. So if you speed up or slow down tracks (for instance to beatmatch - fairly normal, no?) the key will change.

There are two ways to deal with this: Firstly, engage key lock on your software (often works fine if you're only pitching up or down a little, but otherwise can sound ropey), or mix in key but make your mixes quick cuts from one track to the next and don't beatmatch, relying on the similar key to make your transition sound smooth.

Trial and error will help you here, but I think the bottom line is that this is a tool, not a way of mixing, and you'll use it where it makes sense with either of these methods. Of course if songs are very close in BPM anyway, you may choose to put up with a slight deviation in key. I'm sure you'll quickly learn at what point it starts to sound bad. I'm going to find out tonight!

How does it actually all work out at a gig?
So - that's the theory. I've marked up my tracks, imported everything into my DJ software (I'm using Serato ITCH this evening), and I'm ready to head off to the gig.

My thoughts at this stage?

  • I'm going to play a lot of old music as well as new tonight, so I've got enough stuff in similar keys to really test this out
  • I'm worried that keylocking will make my music sound rubbish sometimes
  • I've not actually practised at all - I'm going to experiment live. That's just me, though - I like to add a bit of risk sometimes!

• In part 2, I'm going to report my actual experiences of trying to play a whole DJ set mixing only in key: Go to Mixed In Key Review part 2.

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  1. Great post, with epic timing on it as I have just finished putting together a mix where I use the key clock of mixing between an hour of any given key. I plan on mixing it down this week so I will post a link so some kats can check it out... I think it can definitely add some spice and professionalism to your mixing but in the same breathe sometimes you gotta just mix what you feel is the best... Overall I'd say its a great tool

    • Phil Morse says:

      Am just writing up my experiences actually trying to DJ with the key codes Mixed in Key generated for me... was certainly an experience doing it for the very first time in a busy venue! Will be great to hear your mix when it's ready.

  2. I've used harmonic mixing in my sets for couple of years now. After picking up the concept, I've been figuring out the key of the tracks by hand (like Dubfire used to). I'm still doing it the hard way, but buying the software isn't too far fetch idea.

    The biggest impact of harmonic mixing to my DJing was that now I can play tighter transitions. I'm not playing acapella's or borrowing loops from the next track, but now I can drop the next track in when ever I feel like it.

    The best effect is when both tracks, A and B are dropping to the breakdown at the same time. Always a jaw dropping transition!

  3. "I’ve not actually practised at all – I’m going to experiment live. That’s just me, though – I like to add a bit of risk sometimes!"

    Haha, sweet! Can't wait to hear how it went.

  4. Ive been mixing in key pretty much since I picked up mixing. Its the best & easiest way of finding mixes with new tunes and can really give you a head start.

    acapellas are a different beast though. Im most music the vocals are not in the same key as the melody, they are in a complementary key. So using the camelot wheel goes out the door. I found myself mixing 12A's with 4B acapellas, random.

    A good, FREE alternative to mixed in key is rapid evolution. I use it exclusively. Its not the most user friendly, but gets the job done on a tight budget.

  5. To Howitzer: great tip about Rapid Evolution.

    While acappellas doesn't of course HAVE to be in the same key as the music, generally vocals are. A voice is just another instrument, and unless it's in a particular key or a related one, it's going to sound a little weird. (That's not to say it won't sound good, of course.) :)

  6. I've been using Mixed in Key for years now and I love it. I even developed something I call "dj notation" that helps in timestamping buildups and breakdowns so that I know when to mix that next track. Detailed info here: http://www.djnotation.org/Harmonic-mixing

    Thanks for reminding me that harmonic mixing is not as widespread as I thought.

  7. Hi Phil,

    OK, I'm an amateur Dj from Panama City, Panama.
    I just got the Numark NS7, I found your website wich is pretty cool, great tips.
    My Favorite Genre to mix is Hip Hop and Reggae, I wonder if Mixed in Key software will help to make more accurate my mixes. I think sometimes I take to much time finding the next track, the right one...


    • Phil Morse says:

      No, it will improve mixes that are already good, but mixing in key is not the most important thing about music selection... I'd work on the way you sort out your music first and practise more so you are more likely to know what you want to play next when you're playing live... mixed in key is the icing on the cake.

  8. Hi all,
    I'm an amateur dj too. I'm from vietnam. Ho Chi Minh City.

    I'm really to learn more and more.
    I dont know how to used the Mixed in key. Can you help me pls.
    Many many thanks. send my email.

  9. Great write up!! Mixing in key is great knowlage to have. Ive been doing it since I started out in 1982 without ever really realising it. I learnt piano & guitar & theory of music since I was a kid so I suppose it just "sounded right" when it came together! Mind you I've taught quite a few DJs over the years and the ones with musical background seem to get a grasp on this a lot faster and easier those that have no musical training.

  10. hai am using virtual dj software.i have one dought about mixed in key .ican use camelot key in virtual dj software?because harmonic mixing very tough for me.

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