MOJO: Horn Section Review | Sound On Sound

“Vir2 Instruments have done a fantastic job with Mojo. If you put in the time, you can pull off some convincing arrangements.”

Has your music lost its mojo? Maybe Vir2’s new horn library can add some magic…

For many composers working with MIDI, horn sounds for pop, funk and jazz pose so many challenges that many of us have resigned ourselves to the feeling that we’ll never get real‑sounding horn lines out of our sample libraries. While we were off lamenting and daydreaming about having a big enough budget to hire Earth Wind & Fire’s horn section, the good folks at Vir2 Instruments were busy trying to solve this colossal conundrum.

As a trombonist and big band arranger, I personally felt defeated — even embarrassed — by my lack of aptitude when it came to creating realistic horn parts, even with an arsenal of horn libraries. (I blame myself, because many of these libraries contain the articulations to get the job done but I tend to find the process of getting the right articulation in the right place counter‑intuitive and tedious). Vir2 Instruments must have heard my distress call, because their new horn library, Mojo, could be the solution to my problem, claiming to be a complete horn section that is as versatile as it is intuitive. Could it help me get my mojo back?

Brass Tacks

Mojo is a full suite of horns geared for jazz, latin, pop and funk music production. If you were hoping to get French horns, tubas, euphoniums and so on, I’m afraid you’ll have to look elsewhere. What you do get with Mojo is 12 instruments packed with (almost) every articulation you’ll need to get your arrangement swinging. These are Alto Sax, Baritone Sax, Bass Trombone, Clarinet, Flugelhorn, Piccolo Trumpet, Soprano Sax, Tenor Sax, Trombone, Trombone Mute, Trumpet and Trumpet Mute.

Mojo Horn Section uses Native Instruments Kontakt Player and can also be loaded into a full version of Kontakt. Installation went without a hitch for me, but, as with all modern libraries, it’s a good idea to check for updates before you dive in. The library weighs in at a respectable 15GB and, as with any library of this size and depth, it can never have enough RAM. Vir2 recommend 4GB. You’ll need a fast drive, but I think every savvy SOS reader (is there any other kind?) is aware of that sort of thing by now. Copy protection is handled through Native Instruments Service Center and, as long as you remember your user name and password, is relatively painless.

I would recommend spending an hour or so with the manual before you jump in with both feet. Besides the keyswitch chart (that you will need by your side for your first adventures with Mojo), it answers many questions about the library.


Load up Mojo and you’re met with a somewhat bare interface. All the usual Kontakt features are available, but as far as Mojo-specific controls go, only two knobs are present: ‘Players’ and ‘Mode’. Everything else is hidden in menus. The Mode knob selects Polyphonic, Monophonic or Legato play. The Players knob is slightly more interesting and lets you adjust the number of players on any instrument from one to 10. This can be incredibly accommodating. If your arrangement calls for four trumpets in unison, just set the knob to four players. This feature is very attractive to arrangers for testing the balance of their arrangements. (As you probably know if you’ve tried this in other libraries, you’d usually need to have four trumpets loaded on different tracks.) If you don’t care how it would really sound with a band, go ahead and double, triple, or decuple your players for a bigger, fatter sound.

Although Mojo doesn’t load up a different sample set for each player, it does offer some effective tools to fool the ear into thinking it’s hearing different players. Those tools include spread position, detuning, and velocity and timing variations. The Mode and Player knobs are also controlled with keyswitching, making it easy to record changes in your sequencer.

Each instrument comes loaded with every available articulation. This alone is refreshing, as it saves you the trouble of scrolling through dozens of articulations, plus you need not know ahead of time which ones are needed. Load the alto sax and, via keyswitching, you can access any nuance Mojo has to offer. The down side to this is that you have to load all these articulations into RAM, even the ones you aren’t using.

Before I move on, I have to point out a few chinks in the Mojo armour. The keyswitching is all over the keyboard, and you’ll need an 88‑key controller if you intend to be a power user. I have a 76‑key controller and all but wore out my octave up/down buttons during this review. To be fair, I don’t know of a better arrangement, but I think this is something that could frustrate users. Fortunately, most of the switching is the same for each instrument, and if you think you can do a better job with the layout than Vir2 did, the option to reassign the keyswitches is there.

In Use

Mojo’s sound quality is excellent and highly usable. The samples are 24‑bit stereo and were recorded with top‑of‑the‑line vintage gear, but what I responded to was the quality of the actual recording of the instruments. Mojo’s horns are up-front and in-your-face, and the different articulations really give you what you need to put together a colourful arrangement. Besides the usual suspects, like sustain, vibrato and staccato, you get at least a dozen more, including doits, fall‑offs, octave runs, swells and trills.

A slight quibble to note here is that some articulations are missing from some instruments for no apparent reason. Why would there be a ‘slur up’ on the tenor sax but not on the alto? Also, while the swells sync to your sequencer’s tempo (very cool), the octave runs don’t.

I first used Mojo on a big-band sax soli section I was working on, and I was able to program the scoops and vibrato as promised. I needed to play with each note’s velocity to get it to sound natural and the end result was exceptional. I then worked on a tutti brass portion of the same tune and was equally impressed. The trumpets and trombones had real punch and were even easier to program than their reedy counterparts.

Next, I put Mojo through its paces with a funk tune a la Incognito or Tower Of Power. Vir2 mention TOP as an influence for Mojo, so I was surprised to be underwhelmed by my results. I was able to trigger articulations I wanted, but the overall sound was somewhat ‘synthy’. I went to Vir2’s web site to listen to their demos (which are outstanding) and felt the same way about their funk offering as I did about mine, so it could just be a matter of taste.

However, I put Mojo to the test on a range of projects, and for the most part it delivered. I can’t say that it always convincingly sounded like the real thing, but it came closer than other libraries I’ve used. Mojo is not a magic wand, and to get the most out of it you need to do a lot of tweaking: not deep, under‑the‑hood editing, but be prepared to move keyswitch notes around and play with note velocities in your sequencer. This isn’t a shortcoming of Mojo, but rather a reality that, when you think about it, makes sense.

I know you’ll be clamouring to know how the solo instruments sound and I’m sorry to report that, even with their legato scripting in the background, the result is not fantastic. It’s usable, for sure, but I can’t imagine producing a realistic sax solo with Mojo. This isn’t to say that Mojo fares worse than the competition on this front, because it doesn’t. And, to be fair, I didn’t try the provided wind-controller patches.

Rounding Out The Selection

As well as the 12 instruments already mentioned, Mojo also comes with light versions that use fewer samples but contain the same number of articulations as their larger siblings. This can be very helpful when you have a full big band loaded. You have the option to use the light version while programming, and then switch to the full version before you bounce.

Another exciting feature is Mojo’s release samples. In the past I’ve written these off as RAM hogs with no perceivable advantage, but Mojo puts them to great use. For instance, you can easily (through keyswitching) hold down a brass chord and have a fall‑off occur as you release the keys. Besides creating a more realistic passage, this feature allows you to select the release keyswitch while your chord is held down, as opposed to triggering it immediately before the fall‑off. Very handy indeed. Hopefully, Vir2 will also add stabs as a release sample.

Mojo also contains a library of almost 2000 horn riffs. Although, at first, this seemed like a major selling point, and while some users may be able to incorporate these riffs into their music, I found them to be something I would look to as a last resort. I’d also prefer them to be laid out in a construction-kit style rather than being arranged by instrument, as they are. Also included are Multis, intended as a starting point for laying down section parts quickly. This is a nice inclusion, but honestly you’ll come up with your own, more usable, combinations right out of the gate.

Mojo includes a full gamut of effects, including reverb and compression. They sound great, but not necessarily better than what most of us have in our DAWS. However, they are easy to instantiate and are horn‑specific, making them a nice addition.

One add‑on I think especially useful and well done is the special effects section. Here you’ll find growls, zany runs, slides and more. As a composer for cartoons, I can see myself using these a great deal.

I was disappointed that a jazz flute was not included. I use flute in many of my pop, funk, jazz arrangements and find that the flutes in symphonic libraries just don’t cut it in pop music. For me, a flute would have been more appropriate than the included piccolo trumpet, or even the soprano sax.


Vir2 Instruments have done a fantastic job with Mojo. If you put in the time, you can pull off some convincing arrangements. Perhaps after logging in the hours, you could even put down realistic parts in real time. The sections are very authentic and the solo instruments, while not the real deal, are as good as I’ve heard. Although there’s perhaps some room for improvement, if you use horns regularly in your MIDI arrangements, you need to get your Mojo!

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