Interview with Mario Krušelj

SoundBytes talks at length with Kontakt scripting master, Mario Krušelj.  If that name is not familiar to you, perhaps you know him as the prolific music-forum contributor, EvilDragon.


by David Baer, Sept 2015


Mario Krušelj has had his hands in any number of Kontakt sound libraries we’ve covered here in Points of Kontakt.  He has provided the scripting for instruments from Hollow Sun, Hideaway Studio and Sonokinetic, to name just a few.  He is also a prolific contributor to a number of music forums and is an invaluable member of the NI Kontakt forum, where he generously dispenses his deep knowledge of Kontakt development.  If you spend any time at all on the main music forums, you will almost certainly come across posts by EvilDragon, Mario’s internet alter-identity.

SoundBytes Magazine  is pleased to present this in-depth interview with Mario in what follows.


SoundBytes Magazine: Tell us a bit about your early musical experiences.

Mario Krušelj: First of all, hello to all readers of SoundBytes magazine from a very little and unremarkable town located on the very east of the small country that is Croatia (for the truly curious: ).  Let’s see … I wonder how far back do you want me to go on this one!  As a kid, I was always fascinated by any and all things that made sounds when pressed – especially if they had pretty lights on them! So that would be my father’s stereo system, or a VCR controlled via remote (kinda cool – press a button and get that wheezy sound of the tape being rewound, I was entranced with that kind of thing), literally anything that had buttons on it. My parents had to keep all the remotes away from me.

Speaking of my parents, I guess that’s how it all started. In a way, I’d say music got them together. My father is a self-taught tamburica player ( ), playing bisernica, and he was playing in a local folk group, where my mother danced and sang. That’s how those two hit it off! Sometime later, they had me. I was told my dad used to put headphones on my ears and play the hits of Beatles and Queen at the time to me, as early as me being one year old. That might’ve been the key point, because come elementary school, I was pretty frantic about Queen and just about everything they did!

Back to things that make sound when pushed – at one point (I think I might’ve been 3 or 4 years old), my dad got a Casio, I think it was a CZ-1, just for kicks (I forgot to mention, before he learned himself to play bisernica, he poked a bit of accordion, too). I had no idea about synthesis at a time, but those PD sounds were very fun to me, so I pushed away at it making all kinds of noises! This is another possibly key point in shaping my persona, when I look at things back from today’s perspective.

To cut the story short a bit, then the war came, we were exiled from our home, and there was no Casio to have around for quite some time. Come 1993, we were located in Osijek (that’s the “capital” of the eastern part of Croatia, let’s say), I started going to elementary school. According to my parents, there were some rough times in that period (1990-1998), but we (my sister and myself) didn’t really feel it as such – they tried to provide us with as stress-free childhood as possible. They might’ve succeeded in that, because we knew about the war, we heard the explosions, we saw it on TV, but we were never first-person actors in it. Call it a stroke of luck. Aaaaanyways, I started elementary school, and I think it was by means of charity, but another Casio showed up at our place! This time it was the small SA-21, with mini keys (YES – MINI KEYS!). 🙂   This is where my dad sat down with me and taught me to play some simple pieces, like Jingle Bells, and stuff like that. I was hooked.

Then when I was in 2nd grade, my parents asked me if I’d like to go to music school! Of course I would say yes to that! So starting 3rd grade, I started elementary music school, for piano. Although, the professor interviewing us took a gander at my fingers, saw how nice and decently long they are, and she wanted to take me under her care, and violin classes! I was adamant about the ivories, though, so that’s what it ended up being. Just a note – initially we wanted to take synthesizer classes, but that’s just a two year course, not an actual 6 year piano curriculum, so in talks with the professor interviewing us it was decided for me to take up the piano – my parents cringed because now they had to find a piano, and times were a bit tough! They managed to find one quite affordably, though.

Damn, five paragraphs and we’re still in elementary school! I’ll see if I can speed this up somewhat. Elementary school done, elementary music school done (as the best of my generation). Time to enter high school! This is where a few things happened: I heard something other than Queen (told ya I was fanatic about them) in my life – it was heavy metal. Bands like Sonata Arctica, Rhapsody, Nightwish, etc. All very melodic, and (usually) fast! And … synths! That piqued my interest, especially at later point when I heard Dream Theater, which was my first foray into more complex and progressive music. So there was a lot of that. Then, I saw Jordan Rudess do magic on his Kurzweil K2500 at the time. I was flabbergasted! I think that was the first serious case of GAS that I had, at the sensitive age of 16. And another thing, we’ll probably get more into that later, high school was also the time when I was first introduced to sound synthesis, courtesy of (would you believe it) NI Generator (Reaktor’s grandfather)! One computer in the school’s computer classroom had it installed, and needless to say that is where my computer studies classes went to, haha (although it was absolutely not a part of curriculum, but I kinda nailed the regular curriculum stuff quite fast, so I could have my fun with Generator!).

Nearing the end of high school, I also got interested into guitar, so I started teaching myself how to play it. It was hard at first, since the concept is so different from the piano, but I can proudly say that after some 10 years later I don’t suck as much as when I started out!

So I think that’s basically it for “early music experiences” – covered about half of my life!

SB: I know that Kontakt is far from being your only area of expertise in the realm of electronic music, but clearly it’s the software most readily associated with you.  Tell us how it was you became one of the world’s most accomplished Kontakt scriptmeister.

MK: Purely by chance, sprinkled with a bit of my natural curiosity! It was during Kontakt 3.5/4 times in 2009, I was exploring what it can do, as an avid manual-reader (lost art today, it seems!), so after I figured out all its regular nuts’n’bolts as far as synthesis and FX goes, I took a gander at this scripting thing. I’ve always been interested in programming, going back to elementary school where they taught us LOGO (the tiny turtle that likes to draw stuff according to the algorithm you provide it!), in high school I got some understanding of C syntax and how things work in general, so that got me hooked. From there on it was mostly a ton of hit-and-miss, referring back to the manual, and just plain trying stuff out and seeing what can be done. Also exploring the factory scripts was quite helpful.

I might not be 100% correct on how things happened from that point onward. I did a few small scripts on a personal/private basis for like $50-100 and the like, it was great at that time considering I had no job, was still a student, and living with my parents. I know I’ve been exploring what other people did with Kontakt, so inevitably googling about KSP led me to VI-Control forum (before that I was a member of NI forum since as early as 2007, also got some knowledge from the KSP subforum there), and its Kontakt section. Learned a lot there. That’s where I connected with some devs, most notably Greg from Orange Tree Samples. Greg was (still is) a class act guy, he’s just so open about discussing everything so we hit it right up. Back then I was a huge MSN Messenger user, but VI-Control had links for AIM Messenger, so we connected through that. Discussions were varied and many, it was also kinda interesting since Greg started OTS just a year before (2008), so he was relatively new too. But he had the know-how! And I picked up a few tricks along the way, traded some of mine back, etc.

Then the key moment struck! Greg was very busy scripting the next huge Cinesamples library (VOXOS), and CS guys wanted to release something else in the interim, so they were looking for somebody to do it. Greg recommended me, but he asked me beforehand if I would be up for it. I didn’t feel very confident in my abilities back then, so it took a bit of persuasion and “I’ll be around if you get stuck” from Greg, but the payment was quite tempting, and I did admire the Mikes on the work they’ve done so far. So we all had a group chat via AIM and arranged the proceedings! I was busy throughout May 2010, slicing their 900-something samples in Kontakt’s Wave Editor, then scripting controls for what would become Deep Percussion Beds. That, my friends, was my first proper commercial gig ever!

After that, I started putting my contact in the signature on the forums I frequented (NI, VI-Control, KvR), and not too long after that, some chaps from Netherlands contacted me, perhaps you’ve heard about them – they call themselves Sonokinetic. 🙂   Their libraries thus far were very rudimentary as far as scripting goes, so they wanted to up their game and improve in that area. I believe it was the Deep Percussion Beds release that prompted them to contact me, so they outlined their project idea, and we talked about it. It was the beginning of their highly successful range of vocal phrase libraries – first one being Tigris&Euphrates. It was a decent amount of work, however it turned out great and they were very satisfied! So they came back for more. In total, I did seven libraries for them (for the curious: Tigris&Euphrates, Desert Voice, Voices Of Israel, FE, EMP, Carousel, Toccata). Best of all, we became quite good friends, as well. We still are! They’re good people, and their latest achievements are IMHO absolutely stunning, as far as phrase libraries are concerned. They’ve mastered that concept and they rule it like nobody else on the market. I’m glad I was the part of creating their brand in a way. A lot of what they do now harks back to those first vocal libraries they did with me. It makes me proud and humble at the same time.

Somewhere amidst T&E scripting days, if my memory is to be relied on (sometimes it’s not!), I also got an unsuspecting e-mail from the one, the only, the legendary, Stephen Howell of Hollow Sun. If I remember correctly, he spotted my signature offering KSP work on KvR, but my memory is quite hazy on the details (toldya you shouldn’t rely on my memory, haha!). In any case he did contact me, telling how he was quite at his wits’ end with Kontakt’s KSP and that he’d rather handle everything else except scripting, so if I were up for it, he had an idea he wished to make into a product, but he couldn’t wrap his head around scripting it himself. All good and understandable, we continued discussing via e-mail, and eventually, HSDV was the result of all those talks – I am not sure if there were any proper drum synthesizers in Kontakt format before that, somebody please correct me if I’m wrong. So that would mark a first, both for me, and for Kontakt world in general. The pattern that happened with Sonokinetic repeated – Steve and I became fast friends, he admired my work highly, so he always returned with more projects. It ended up being a great friendship – we would chat it up almost every day, first via MSN, but later Skype, as MSN faded away.

I would say those three connections were ultimately crucial in establishing myself as a freelance KSP developer. I was getting e-mails from various people, mostly through word-of-mouth from other developers who worked with me, rather than my forum signature 🙂 So the number of projects I was involved on increased, as did the scale of projects in some cases (I would like to list Evolution Series World Percussion and Output REV as examples of two such greater scale projects). Best of all, I’m still in touch with everyone I worked with, and they’re spread all over the world, from USA to Australia! Makes it a bitch because of all the time zones, but oh well … I’m really grateful for the experiences that I had (both good and bad – it’s not always roses!), because I got to meet and work with some amazing people. I gotta stop typing now because I might tear up.

No, really. It’s been a helluva ride so far! But the best part is – seems we’re not running out of gas anytime soon! 🙂

SB: In working with Stephen Howell, what was your relationship?  In other words, did you provide input to the creative process, or was all the delightful madness solely attributable to Stephen?

MK: That’s a good one. For the most part, Steve would come to me with an idea for a product, usually with a GUI mockup already done, and then we’d talk a bit about it. In most cases I’d have some input on the layout of controls, and perhaps some added functionality. “FEATURE CREEP!”, he used to yell ever so often, haha. 🙂 

For some other products, I mocked up the way I envision the GUI. For example, the vKS70 layout of controls and everything was done by me. Also, vKS20 LCD display is actually completely done by me, pixel by pixel (I swear I don’t have OCD!). I have a penchant for color-coding things, whereas Steve would just make things quite drab usually. For example, in Cognosphere, his first mockup had all knobs black, so it was kinda hard (IMHO) to navigate through it. That’s when I suggested having colored knobs depending on which of the six layers is selected. And to keep both of us happy, we added a switch to change between drab and colorful modes, so people can choose on their own what they like better. Similarly, changing the color of vKS20 LCD was my idea. “A fucking Croatian Christmas tree!” was what Steve would usually quip! 🙂 

I always provide my input and feedback to anyone who employs me. So far, I have a pretty good track record of being damn spot on and having a lot of that input accepted and implemented. I’m happy about it – although I don’t consider myself a great UI/UX designer, but I do have a certain level of understanding of these things, since they became my livelihood.

SB: What is the future of Hollow Sun?

MK: For the time being, it’s going to continue to plod along. I do have one project underway, and I’m quite ecstatic about it since it’s a VERY rare machine (and no, I’m not gonna tell you what it is – let’s keep the suspense!), but it’s going slow, since right now I’m very much into finalizing my M.Sc. thesis, so that takes up an awful lot of my time, and the other thing is working with Umlaut Audio, which in due time might prove itself as the main thing that I will do – we’ll see about that. If the offers become too good to pass, I will have to see what to do with HS. I don’t want to quit doing it, but the development pace might become glacially slow, which is not to my liking, and I assume it’s also not to customers’ liking either. The important thing to state here is that HS was (and still is) the main source of income for the Howells, so that’s something I simply cannot turn my back to.

SB: OK, two part follow-up question.  You haven’t even mentioned your undergraduate studies, let alone the fact that you’re working on your masters.  Please fill us in a little more about that.  Also, who (or what) is Umlaut Audio and why might it loom large in your future?

MK:  Right, I forgot about my scholastics! I don’t find them particularly important (something Steve would very much agree upon, haha), but here goes. I am studying a course called Process Computing at Faculty of Electrical Engineering in Osijek, Croatia. So, essentially, it’s computer studies. I had gotten my Bachelor’s a couple of years earlier, the thesis was on additive and subtractive synthesis, which I’m perfectly at home about, so I passed with flying colors.

My Masters degree thesis is about converting images to sound using additive synthesis, but in a slightly different way – like being able to select exactly which area of image you want to target for converting via vectors (and then being able to select multiple areas of the image, even overlapping), and then using some additional parameters to influence the resulting sound (like which harmonics are generated, the base frequency, the length of the scan through the masked area of the image, etc.). Exciting stuff that will mostly result in totally weird sounds! Hey, it might be useful in providing source material for a new MLM, or something!

As for Umlaut Audio ( ), it’s a fairly new prospect that was brought to my attention, and I am currently positioned as their CTO – keeping tabs on all the cool sampling related tech, doing scripting, and in general consulting about all that sort of thing. The idea behind Umlaut is to produce branded libraries for working composers – instead of purchasing the library that is available to anyone with enough cash, you can have your own personal library created by professionals “in the know”, with your name on it. Depending on the agreement, the client can keep the library exclusive, exclusive for a period of time, or non-exclusive (in that case, Umlaut would sell the library with client’s sounds later on). This concept is something that nobody has done before as far as Kontakt’s niche is concerned, and it’s already making waves in the relevant circles… which means there’s potential for a lot of projects, which means a lot of work… and eventually income, as well. This is why I think Umlaut could become very important to me, in due time. We’ll see how it pans out in the long run!

SB: Are your music-technology pursuits your full career or do you have some kind of supplementary source of income? In particular, have you ever done (or just contemplated doing) general computer software development of any kind?

MK: Incredibly enough, I get by quite alright just by doing KSP scripting! I’m not as rich as a rock-star, but it pays the bills and for food. I guess one important factor here is that I’m living in Croatia, and currently in my grandfather’s flat (so not paying any rent), so the cost of living is lower than in, say, Germany, UK, or USA. [Editor’s note: Marios studio (in the lair of the EvilDragon) pictured right]

I would love to pursue some other money-making avenues at some point, too. I play keys and guitar, would love to have my own band. I’d love to compose stuff (I did so quite some time ago, but ever since I started scripting I’ve been in a slump). But most importantly, I’d love to have my own recording studio, which would be affordable to demo artists so they can create those oh-so-important showcase demos etc. Music production and mixing is VERY interesting to me, so I can see that as something that could satisfy me as much as scripting does.

As the saying goes, when you work something that you love, you’re not really working. And I can tell that it’s absolutely the truth. Scripting for Kontakt created some amazing friendships and led me to meet some really cool and awesome people. That’s something I would never thought it could happen, but I assume a big part of why that happened is my approach to work, which is in fact quite casual and relaxed on one side, but at the same time serious, focused and professional. It seems that that approach resonates well with everyone who employed me so far, so I’m just going to continue working that way. 🙂 

SB: If you could have any improvements to Kontakt for which you dream up, what would they be?

MK: Oooooooh, boy. Down the rabbit hole we go, eh? 🙂 

If we’re talking purely pipe-dreams, there’s not much that I have in that regard except perhaps one thing – KSP should be extended with additional functions so that it’s able to make coffee. Or tea, if so preferred! Pretty much all the features I’d like to see in Kontakt are real-life useful ones that would facilitate working in Kontakt, but they are usually developer-driven, so not that useful for the casual user … One thing that’s a biggie, even for users, is being able to drag-and-drop rearrange groups. That’s a huge one, but I am not sure it will ever happen, since I think it relates directly to the NKI file format… so it’s very tricky (I assume) for NI to actually go ahead and implement that. On the other hand, that feature doesn’t exist in any of the competing samplers, either, so that’s something to take into account.

I’d love for Kontakt to have many more effects, and higher quality of them. MachFive 3 has Kontakt beat in this regard, hands down. There are sooooo many effects in there, it’s ridiculous. Some are things that are sorely missed in Kontakt – like a proper ensemble effect, or a ring modulator, or an 8-band EQ, or a tremolo effect (sure you can do tremolo with an LFO, but it’s tedious having the LFO in every group – that’s one thing Kontakt is lacking, modulators at group and instrument level, not just per-voice), there are no multiband compressors in Kontakt… There’s quite some room for improvement there. Some of it might actually happen.

I guess I could go on and on about this, but really most of feedback I provided to NI (I do beta testing for several companies, including NI, u-he, Modartt) is about development features and bug reports. Lots of bug reports. Most of the bugs are very specific and usually the casual user wouldn’t stumble upon them, but that doesn’t mean they shouldn’t be fixed. We’ll see how they’ll handle that in Kontakt 6. 🙂 

SB: And what about something that NI might actually provide in a future release?

MK: A sleeker GUI is definitely in order. Perhaps not straight away in K6, but NI is very aware of that, Kontakt is currently one of the oldest (along with Reaktor) products in NI’s catalog, and it shows. Reaktor got its huge GUI update in 5.5, Kontakt might need to wait some more. But it would definitely make a ton of sense to refresh the interface so that it is more similar to Reaktor’s and Machine’s. Same sleek, flat, dark interface with great contrast. That will be good when it happens.

Improved performance with huge instruments is another thing. There are still some optimizations to be made here, especially when we’re dealing with a couple thousand groups and dozens of thousands of zones – not terribly important for Hollow Sun per se, but orchestral library developers would definitely welcome this. Let me also use this moment to state that Kontakt is THE ONLY sampler on the market that can swallow those huge instruments with such ease and efficiency. MF3 falls over when trying to do the same thing. Others are simply no comparison – no matter what you compare. CPU and RAM efficiency is the best thing about Kontakt really. A lot of people dismiss that, but it’s the truth. This is also the reason why you never saw a very elaborate BIG orchestral library for MF3, or Halion 5, or MAGIX Independence. PLAY and Vienna are closed systems so I’m not taking them into account.

Next, I count on NI improving KSP and adding more features to it to make development even easier. There are still some engine parameters that cannot be changed via KSP, and it would be great to change that. Fingers crossed!

SB: So far we’ve talked mostly about Kontakt.  What else makes you want to get up in the morning?

MK: What makes me want to get up in the morning? Breakfast! 🙂  I do like keeping tabs on the virtual instruments and effects world. I have a decent bunch of them! I also check out what’s happening in the hardware world from time to time (keyboards, synths, guitars, effects, stuff like that). Then of course, forums, I love forums! If you’re into music production, you’re certain to bump into me somewhere: KvR, Gearslutz, NI, Cockos, VI-Control … I’m frequenting those places.

Most of all, and I know this sounds corny, but I love waking up just to see my wife and confirm that we made it through to another day together. Happy, happy! 🙂 

SB: What advice can you give to those wishing to follow in your steps to become a master of Kontakt scripting?

MK: Best possible advices I can give are these: first and foremost, RTFM! A lot of info is right in there, and there’s a bit of stuff to get you started. Second, do not be afraid of making mistakes. Trial and error is crucial and best way of learning how to do things properly (at least IMHO). Even I had a ton of “lightbulb moments” during my early days, after being thoroughly annoyed about things not working. Those moments are precious, and WILL improve your understanding on how to deal with a certain problem! Third is related to second – have patience. Don’t give up after five minutes and go post about it on the forums asking for somebody else to do it instead of you. I might stop doing that in the future 🙂   Fourth – SEARCH the forums before posting. There’s already a LOT of scripting tidbits both on NI and on VI-Control forums, so take advantage of it. Take some time to go through all the threads. Consider the KSP info on those two forums as unofficial treasure trove of info that is lacking organization (thankfully there’s a search function, but you gotta know how to search, too). And fifth and last – it REALLY helps to have prior programming experience. I cannot emphasize this enough. Scripting is not for everyone. You need to have an analytical way of thinking, and you must be able to think outside of the box (what is often referred to as lateral thinking). If you’re not good in either of those areas, scripting won’t come naturally to you, and you’ll just end up being frustrated. In that case, it’s probably best to save up some cash and employ a proper full-time scripter to do your bidding (shameless plug, I know!) 🙂 

SB: Mario, it has been a real pleasure talking with you.  We want to thank you for your time and wish you the best of luck in future endeavors.

MK: Thank you as well for the opportunity, David!


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