Review: Mixed In Key 5

Review Summary:

Mixing in key has gone from being a novel add-on to pretty much essential in my own DJing - I always consider the musical key for every mix, even if I choose then not to act on it. Mixed in Key is simple and well explained, and while there will always be arguments as to whose software is the most accurate, it's certainly good enough.

Mixed In Key 5
  • Mixed In Key 5
  • Rating: 4
  • From: Mixed in Key
  • Price: $58 ($29.99 to upgrade from previous versions)
  • Reviewed by:
  • On September 30, 2011
  • Last modified:August 18, 2014
Mixed in Key 5 comes with a tutorial to make introducing this technique into your digital DJing as simple as possible.

Mixed in Key 5 comes with a tutorial to make introducing this technique into your digital DJing as simple as possible.

Review: Mixed In Key 5

Mixed In Key 5 (US$58) is the latest version of the market-leading key mixing program, which allows DJs to exploit this advanced and highly musical technique in the planning and playing of their DJ sets. Claiming such big names as David Guetta and Pete Tong as regular users, it is the most heavily marketed of the key detection systems currently available to DJs.

Adding a music player, key search engine, multi-key detection, better file compatibility (M4A and MP4 are added), and a claimed improvement in accuracy, Mixed In Key 5 also appears to be the most complete version of the software to date. Let's put it through its paces.

An introduction to mixing in key

Mixing in key or "harmonic mixing" is one of the great musical leaps that digital DJing has put in the hands of just about anyone. Anyone, that is, who's not tone deaf and who is prepared to put in just a bit of work to understand what it's all about. This technique can make any DJ set sound many times better, helping it to flow, suggesting excellent musical pairing the DJ might not otherwise have thought of, and making impromptu "mash-ups" a cinch.

Once the realm of musicians-cum-DJs and a small number of other DJs who took the considerable time necessary to work out how to do it manually, now - thanks to products like Mixed In Key 5 - it is possible for all DJs to explore these techniques.

How it works

Mixed In Key's big leap was to take the musical theory behind key mixing and make it accessible to DJs, by doing two things: Firstly, it detected the key of a tune automatically, and secondly it represented this in a way that the DJ could immediately use to try key-compatible mixes.

What is musical key?
All music has a key, and most Western music and practically all dance music is pretty simple - it will be in one of 12 keys and will be either "major" or "minor". Music in the same key mixes well, and music in related keys mixes well too.

Musical key

You no longer need to understand all of this stuff to use key mixing in your DJing.

But the beauty of Mixed In Key and similar programs is you don't need to understand any of this, because by following their system, you just look for tunes that the program tells you are likely to match, and mix away.

While mixing in key certainly doesn't guarantee a good mix, and while such software doesn't always get its analysis right, as long as you use your ears too, you can discover great mixes far faster than you would if you spent the time to "key" all your tunes manually (it's possible - if you have a piano keyboard, some musical training, and about six months).

In use

Mixed In Key has always been simple to use. It opens a small window into which you drag your tunes. You give it some basic information (where you want it to record the key information, ie in the "comments" tag, in the filename, in the "key" tag of the MP3; whether you want it to add tempo information too; what key notation you want it to use - its own "Camelot notation" is default and is one of its strengths, so you won't want to change this), hit "start", and off it goes.

The new version has dual core support so whizzes through your tunes faster than ever if you have a dual core processor, but nonetheless you'll want to leave it running overnight for the average collection - mine is about 500 tunes and it still took an hour or two.

Quality of key detection
Mixed In Key's makers have in the past stressed it is optimised for dance music, but also have rewritten the key detection algorithm for this version and are overall claiming it to be the most accurate ever.

Key changes Mixed in Key 5

Notice how the software has spotted multiple key changes within the track. I believe this track is definitely one key all the way through despite what the software reckons, but it's a useful tool to have in addition to the simple single-key analysis nonetheless.

You only get a sense of this after DJing with the results for a while, so I can't give you a definitive answer as to how accurate it is, but I'd guess it is going to get things exactly right two-thirds to three-quarters of the time, which is ballpark what the best of these programs manage to achieve. That's why your ears are important - if it sounds bad, trust them, not a computer algorithm! I noticed that the software has introduced a "none" result, for those nosebleed techno tracks with no discernible musicality in them at all! The manual states that these will "mix well with anything" - or nothing, I guess, depending upon your sensibilities!

However, Mixed In Key 5 adds a useful new feature that I haven't seen in other key mixing programs, which is the ability to spot key changes in tracks. It does this by treating each track as segments rather than a whole. Look at the screengrab: You'll see it reckons this tune changes key several times, although the overriding key is "5A", and that's the one recorded in the MP3's tag.

Treat the extra info as advanced stuff, or look at a tune that doesn't sound right and see what's going on - good stuff if you're an advanced user, that is only there if you need it. If you think the software's got it wrong, you can at least look and see if there's a clue why.

From the screengrab you can also see another feature - a built-in MP3 player that allows you to see the key info, and play music there and then.

Searching for key matches
The software now has a built-in search that allows you to click around the Camelot Wheel (its system for showing key) and see what tunes you have in certain keys in order to get suggestions for key mixes. It is even possible depending upon your software to drag a suggestion directly from here into your DJ program, while DJing.

I have smart crates set up with rules in my DJ program of choice (Serato ITCH) that sort out my music so I can instantly do this kind of browsing, but this is an excellent alternative, and its welcome to have it right there in the software.

Using with your DJ software
There's a section called "Connect with DJ Software" which is really just step-by-step instructions for how to get the most out of Mixed In Key with the major software packages.

It's a good addition because it's not always immediately clear how the information Mixed In Key adds to your MP3s can best be utilised outside of the program, and there are tricks here, like how to get iTunes to update its tags so this information shows.

Getting help
One of the strengths of the Mixed In Key's approach is their clear explanations, and right in the program is a tutorial that concisely talks through what key mixing is and how to go about it using this system.

It's necessarily dumbed down, but has links to more advanced resources over on Mixed In Key's forum for the more musical, or those who just "get it" and want to advance to being power users.


Mixing in key has gone from being a novel add-on to pretty much essential in my own DJing - I always consider the musical key for every mix, even if I choose then not to act on it. There are plenty of programs out there that can help you (beaTunes has a great key mixing algorithm built in; Mixmeister and Virtual DJ have key mixing detection built right into the software) but Mixed In Key is one of the most popular, and for good reason.

Mixed In Key 5 browse

Mixed In Key 5's built-in browser lets you look for likely candidates for your next harmonic mix.

By adding multiple key detection within the same tune, and giving users a media player and the ability to search by key right from within the software, and then tying this all up with clear tutorials both on how to use the system and on how to integrate it successfully with your choice of DJ software, Mixed In Key is now more than ever a great one-stop-shop for DJs wanting to introduce this technique into their skill set.

It is simple and well explained, and while there will always be arguments as to whose software is the most accurate, it's certainly good enough. Just remember than Mixing in Key alone is not a failsafe, and does not make you a good DJ per se. You really must trust what your ears are telling you about mixes, and use your music knowledge, experience and intuition to pick the best record to play next depending upon the crowd and the flow, not solely upon what key it's in.

Product Summary

Review Summary:

Mixing in key has gone from being a novel add-on to pretty much essential in my own DJing - I always consider the musical key for every mix, even if I choose then not to act on it. Mixed in Key is simple and well explained, and while there will always be arguments as to whose software is the most accurate, it's certainly good enough.

Mixed In Key 5

  • Mixed In Key 5
  • Rating: 4
  • From: Mixed in Key
  • Price: $58 ($29.99 to upgrade from previous versions)
  • Reviewed by:
  • On September 30, 2011
  • Last modified:August 18, 2014

Do you mix in key? Have you tried Mixed In Key or any of the other systems? Or do you think it's a skill that needs to be treated carefully, and definitely shouldn't fall into "non-musical hands"? Let us know your thoughts on Mixed In Key 5 and mixing in key in general in the comments.

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  1. DJ TechTools have done a smack down of Key analysis tools, but this was a while a go:

    According to that most of the tools only got 30% of the keys right. My views at the time were it prob not worth paying for if its no better than the free tools around. Better off just picking one tool and stick with it, that way it is consistent in its inconsistencies if you know what I mean. So moving between old and new versions, with 'improved' algorithms might just cause a different set of inconsistencies, so if you do upgrade best to rescan your whole collection from scratch I think.

    Personally I have been using the free Rapid Evolution, the beta of version 3, prob the most advanced key detection software out there, but also prob the most un-intuitive to use out there too, that is making me consider buying mixed i key for its simplicity - has it had a price drop, $58 seems cheaper than I remember.

    All the software involved in the tech tools smack down have now been updated so an updated comparison is prob overdue.

    • That DJ TechTools study was done a long time ago. I respect their work, but I did find some flaws in their methods. There were a couple tracks where the musical scores they used were in a different key than the recorded version used for analysis, and they didn't take compatible results into account. When factoring these in Mixed In Key was at 90% compatible results, much closer in line with our own tests.

    • barereklame says:

      Another cool detail with rapid evolution, the inclusion of a software synth. Feel like the algorithm has got it wrong for a tune? Use the softsynth to make your own call.

      The software can be a right mess to configure, though. Some of the settings are almost ensured to mess up your id3 tags, for instance. That is, unless you really know what you're doing. Which can be a little bit of a mystery when running the detection for the first time.

      Copy files, try out on some, check that the tagging results are to your likings!

      • I thing the "proof is in the pudding". I have tested two of these - Mixed in Key and beaTunes - in my DJing and both are up to the job. It's revolutionised the way I mix and I'd never advise anyone not to use these tools. After all, you don't have to follow their "advice", but it does giv e you lots of quite-likely-in-key suggestions. A quick cue in your headphones will quickly tell you whether it's right or not. There's no harm done by tagging your files.

      • i respect your advice when given... hasn't led me wrong yet... I use both Mixed In Key and Platinum Notes and love the both... and I think the updates they did in version 5's look/feel/usage were good too...

  2. I don't know... I'd rather stick with Rapid Evolution for key detection. It's free and writing the key into the mp3 tags is easy which Traktor can easily read.
    I don't see why I should be spending almost $60 on this...

    • Correction to my post above I thought the previous version was $98 but that is platinum notes not MiK.

      I know what you mean, but some time with RE it does weird things like rename tracks with a [1] at the end, like as if its duplicating things. Also tracks come up highlighted in red as if they are missing, when they are not. Initial scans take long time especially as it does other things like beat intensity, fetches, art work, matches etc. The tags list on the far left is also annoying as it only has a small triangle next to a tag to let you know its selected. Its a very powerful tool with many advanced settings in preferences, which for the beginner is off putting. I just wish they sorted out the interface, its been on beta too long now.

      Anyhow after much use and knowing the issues, I do have it what it needs to do for my workflow - I have it set up in a very simple way way that it detects the new tunes in my music library and autoscan the only the key (start and end of the tune) and bpm and then I simply write those tags to group field for itunes and comments field for traktor and that's it. I dont bother to use it for finding matches, art work, music recommendations etc. As I have other means for that, so just wish it was parred down to key detection only like mixed in key and hence simpler to use, weird that the more complicated and sophisticated program is free and the simpler one is is the most expensive, barmy!

      • That's an decent and interesting review of Rapid Evolution you wrote here.

        The problem I have with it is that it always seems to crash on my computers, often within 5 or 10 minutes. Also, it has complained several times already about a lack of memory, while it got 1GB dedicated to it. That is both for RE2 and RE3, and both on 32-bit (Core Duo) and on 64-bit (i3).

        And that's why I, basically, no longer use it.

  3. $29 to upgrade..... wtf. That's horrible. I just bought it like 2 mths ago. That's so wrong! These companies just refuse to reward its patrons.

    • Ivan Smith says:

      I thought the same thing!, and when I received the email from MIK about the upgrade I shot a message back stating that MIK 4.0 was fine and existing users should be given a set number of free upgrades for the initial price.

      $29.95 quite honestly is daylight robbery to add complexity to an already working MIK 4.0. So it now tags M4A's properly? So? MIK 4 does it too and always did - now if Traktor supported ID 2.4 tagging we wouldn't have to put the key in the comments for them to show.

      Also going on and on about Platinum Notes everywhere has been a problem for me with this software -

      Chill MIK, it's ok - not everyone pirates your software but at those prices it may give some cause to do so.

      Just a heads up!

  4. Guillaume L. says:

    Hi Phil,

    Thanks for the review. I've been using MIK4 for few months now and I enjoy the simplicity of it. As discussed many time, it is not 100% precise in key detection, but I think it's better than nothing. Of course, it does not replace human ear...

    Anyway I was wondering if you could answer 2 questions regarding MIK5 :

    - Can you have MIK4 and MIK5 installed at the same time ?
    - Did you have to reconfigure MIK5 completely or did it take the settings from MIK4 ?

    Thanks Phil !

  5. I upgraded from MiK 4 to MiK 5 for free. Got an e-mail with a download-link and now ready to use. Excited to try out the new features! The camelot wheel is really helpful to make mixes sound good, so I really recommend this software :)

  6. I'll stick to using my ears and my guitar to check the keys/harmony.. Mixed in key is cool but I trust myself more.

  7. Personally I think its useful. As I had only recently purchased Version 4, I got a free upgrade to Version 5 and although I havn't had time to fully go into it yet and pass judgement it certainly has a nicer interface and a few neat improvements. One thing I had noticed in the previous version though was that there were a few instances when the Mixed in Key and Traktor disagreed on the BPM. When I manually tapped these out I found more often than not Traktor was often closer to the mark. It will be interesting to see how Version 5 goes in this respect.

  8. Also wanted to mention, I recently had a fair bit of time on my hands and decided to analyse compilation albums and DJ sets of some big trance acts (curiously they were all off the same label). Needless to say that almost every album & set had been harmonically mixed so I think that's says a lot.

    • For certain types of DJing, harmonic mixing is a real godsend. I mix multi-genre and I can switch fast from one genre to another with in-key music, often on the fly, and it sounds great. But as I keep saying, this software can suggest things - you still have to check if it works for those particular songs using your good old ears!

  9. I write the notes down on a piece of paper. Then according to how I remember to match, I do just that. Trust me, harmonic works. When I play songs that are said not to match, people sometimes notice the key clash. When I follow like I'm supposed to, I sometimes blow peoples' minds with what song I pick next. Of course, just like it has always been mentioned, harmonic mixing don't always work. Sometimes, it's best to go by instinct.

  10. For my wav files that have been renamed already in Traktor, is there anyway to analyse them again and not have 2 tags, and also for Traktor to transfer stuff over?

    • MIK 5 should overwrite old tags. We haven't implemented .wav file tagging for Traktor yet because of the method they use interferes with files in Serato. We need to make sure it is compatible with every major DJ software so we don't screw up DJs libraries.

  11. One slight problem if you're running it on Windows that I've just discovered. There's no support for ALAC (Apple Lossless) on the Windows version - only lossy. Apparently ALAC support only exists on the Mac platform.

    I've just converted my whole .flac library (~500GB) to ALAC so that I can play it under Itch, so I'm a little disappointed as it's not much use to me. Hopefully they will fix this soon.

    It's a shame that many software developers aren't able to take a more modular approach to developing their programmes in the first place so that they can easily plugin any codec to support all popular recognised formats, i.e. wav flac m4a, OGG, etc ...

    I'm not singling out Mixed in Key here, but this monolithic approach to programming and subsequent limited format support is forcing the users to jump through hoops.

    • We just looked into ALAC support on Windows OS. We've got a build that works with it but it requires a GPL ALAC decoder to be installed separately on your computer. It should be a feature in the next point upgrade, free for all 5.0 users.

  12. Hey

    If i want to give key mixing a shot where should i start? $60 isn't heaps but i would like to know a little more about it before i purchased software like this.

  13. Just downloaded this, the look and feel from previous versions seems much better to me. The clickable wheel looks like it could be useful as an aid to programming a set, but would be much more useful if collections from previous versions could be imported into the new version.

    Rescanning some of my recent tracks at the minute to see if it effects the tags in Traktor or not (yeah I get paranoid about these things since the Traktor upgrade broke stuff lol), so far so good though.

  14. How about beatport builded in key detection is it accurate I just wonder are they doing it themselfs or artist send them a information?

  15. Stefano M says:

    Ehy, one question, if i purchase the Windows version but maybe in 1 year i will buy a Mac, i can change the product or i have to re-buy it?

  16. Tom Bernaerts says:

    As i read above ALAC is not supported on windows platform.
    The songs i buy on Itunes, are they ALAC or not?


  17. itunes uses the aac format as I suppose to know. It´s something likely linked to the mp4 container. These are all rather guesses but I think I´ll get pretty right, if I say, that MiK 5 will work with iTunes shop songs

  18. Hey

    Does MIK5 let you analyse files without being connected to the Internet?

    MIK4 doesn't and it's really annoying as I often want to do these kind of things on the plane..

  19. Great article.
    I will consider upgrading.
    I don't use it all the time, but in a pinch it works.

  20. now this is an awesome software...i 've downloaded and worth every penny!

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