Sam Inglis:  Hello and welcome to the Sound On Sound People & Music Industry podcast with me, Sam Inglis. Today I'm delighted to be joined by Rok Gulič from OLLO Audio. Welcome Rok. Rok Gulič: Hi, how are you all doing? Sam Inglis: Really well. How are you? Rok Gulič: I'm fine. I'm very excited to be on this podcast because you know, Sound On Sound has been around for many, many, many years and I remember being a teenager when I was, you know, first encountered with a real thing, the printed version back in the days and it was always so special to see things that you couldn't even imagine and of course you know 20 years ago the internet was still a baby. So a lot of things I've learned from your magazines. Sam Inglis: Well 20 years ago did you ever imagine that you yourself would be making products that would be featured in Sound On Sound? Rok Gulič: Nah, not in a million years. I mean, this is kind of like, it feels a little bit surreal if you build it in that reason that you're now mentioning, you know, going from you know, early days of testing audio gear and getting familiar with audio in general and to now where, you know, I'm an active participant in the professional audio industry. So yeah, there like this kind of dream coming true in a way. Sam Inglis: So are you one of the people who's gone from being an audio engineer or a musician to being a manufacturer, what's your route into this? Rok Gulič: Yeah, I've been basically born into a, you know, a musical family. My dad's been playing drums his entire life and he sometimes says that we have a house or a home because of that 'cause just daily jobs were not enough. But of course I've been growing up next to drums and microphones and cables so this is very natural natural environment for me and yeah of course, eventually I became a drummer, I have my own band and exploring sound and signals and stuff, even more in detail later on when I went to college for audio engineering. And then a little bit later on I started this company. Sam Inglis: So in case the name OLLO Audio isn't familiar to any of our listeners, you are a headphone manufacturer and unusually I think ,you are a kind of a boutique headphone manufacturer which is not something we see a lot of in the industry. I mean, we see tons of boutique microphone companies or boutique outboard companies, but relatively few people seem to be making headphones on the scale that you are. Why do you think that is? Rok Gulič: I have no idea really, I can't explain this question in any way. Well, what I can say is that the company really didn't start as a headphone company. The very first product that I envisioned you know, a decade ago was a tactile transducer a sub woofer that you can feel the low frequencies and so on and I was fortunate enough to get a grant from, you know, my local government here in Slovenia to pursue this project and as the project evolved more and more people were asking me about headphones that would go nicely with a tactile experience. And eventually I learned that, you know, having headphones with flat frequency response for mixing and mastering so on is extremely important and at the time it was quite difficult to get something really good. Many engineers were relying on consumer gear. For example, traditionally the Sennheiser 600, 650 series were very popular you know, 15, 20 years ago. So I tried to then design a headphone for me, basically and eventually, you know, a friend wanted one and another friend wanted one and here we go, a decade later we are now a headphone manufacturer. Sam Inglis: Wow. So in terms of the manufacture of headphones then, are you using off the shelf parts or do you build absolutely everything yourself? Rok Gulič: It's a combination. So I mean, completely off the shelf, basically nothing. All the parts are custom made for us. So we've engineered or, to go back a little bit, when I started this project, you know, there was basically zero budget, it was just passion and love to, you know, do something out of nothing as I say sometimes and, you know, using just home tools that you have in your garage basically. So out of that limitation the design of the headphone came about. So we are even today still using very basic tools to assemble these headphones and the side benefit is that they're like super serviceable. You know, if you have like basic skills and you have like a screwdriver, you can fix them, you can replace any part on them. So that's kind of the approach to building these headphones. Sam Inglis: Yes, I was hoping we'd get onto that because I think sustainability is a really important part of your ethos and that just does, that doesn't just extend to making all the parts field replaceable, it refers also to sourcing and you know, you offer a very long guarantee on the product. These are headphones you're just designed to work with for life really, not just for a couple of years and then throw them away. Rok Gulič: Exactly, exactly that is the philosophy, yeah, trying to make everything serviceable for as long as possible and as well as using materials that have as little impact on the environment as possible. So from wood, aluminum, stainless steel, things that can be recycled, as little plastic as possible. Although, truth be told, there are parts that have to be made out of plastic, there's just no way around it. But we try to consciously keep that at minimum. Absolutely. And to go back a little, a couple of questions, earlier, you talked about your goal of wanting to create headphones with a flat frequency response. Now the more I learn about headphones, the more I realise that's not quite such an obvious aim as it might appear because different people have different ideas about what flat means. How do you understand the term flat? Rok Gulič: So flat for me is, I would say it has two sides, so this coin has two sides. One side is the scientific way of understanding what flat is and the obvious flip side would be what you would think personally. What is your taste and what you could consider flat and that could be, you know, quite different in reality and we've been struggling with that. When I say we, I mean the audio industry in general. We've been struggling to come to a consensus on what the true reference frequency response would be either for speakers or for headphones. Even though in headphones it's even more a mess because we need to rely on ear simulators to capture the frequency response and those ear simulators come from different companies and have different response and then we have like this mess around targeted curves and what is scientifically correct. And of course if I touch on the personalisation or taste of individuals, of course that's just another topic that will never end. So for me, flat means something that is scientifically as close as possible to what we as a collective industry kind of agree upon, at least on a broad stroke, but then at the same time, the majority of users, in our case all the engineers will get really good results in translating their mix between devices. So if, you know, if that is kind of covered, then I think we are on the right track and our product does deliver you know, flat frequency response as intended. Sam Inglis: And what is the relationship between the frequency response and other parameters in headphone designs such as THD or sensitivity? Rok Gulič: So the funny thing which with THD is that it mostly comes from material limitations, when you're pushing the membrane beyond what it's designed. The moment you're pushing it, you will create eventually a little bit of THD which is, you know, a part of any instrument, any signal chain, any reproductive product right, so it's always there. The funny thing that many don't really understand is that THD will get higher and higher, or will become audible with higher volumes. So the moment you're turning your headphones up to 90, 95, 100dB you are introducing a lot more THD than you would originally thought so in, in this regard, of course, the frequency response may be measured as the same, but the harmonics distortions will become audible the higher you go in the SPL level overall. Sam Inglis: When the first OLLO Audio headphones came out you had, if I remember rightly, an open back and a closed back model. Currently I believe you only make an open back model. What was the thinking behind discontinuing the closed back version? Rok Gulič: So the closed back was originally based on the open back. Essentially what happened is that one of the British engineers, Chris Brown, asked if we can turn the S4, the original S4 into a closed back version for him and we did that, snapped some pictures, posted it online and people asked for it. So essentially the product was based on the open back chassis and that, obviously it's okay but it's not designed to be a closed back so there were some issues in terms of how to properly tune it and so on. So eventually we decided to make a new closed version but in doing that we had to kill the previous version just to, you know, release the resources that we have as well ,as well as the performance of the S4R version, at least in our perspective was not in par with the open back, so long term it just, we, it didn't feel right to have a product that we know we can do better in the market and basically this serving kind of in a way our clients. So we removed it and built the X1 as the open version and we are currently working on the closed version as well. Sam Inglis: Oh cool and yeah, so I recently tested the X1 and I have to say I'm extremely impressed. I like it, I must say a lot more than I like the S4 originally when that came out, it seems to me to have a pretty flat neutral frequency response right out the gate, which is great. But also you've teamed up with dSONIQ to partner it with a software utility that will flatten the frequency response even more. Do you think this is something that is gonna become the norm in headphone design now? Rok Gulič: Well I certainly hope so. So obviously it's like, it's something special that we have at the moment as a company and being a small company obviously we do need some edge in the marketplace and this individual calibration on one side paired with the Realphones software is great and it does give a little bit of differentiation with our products. But at the same time I do love, you know, music, I love engineering in general and I think that that is the right path for all professional audio manufacturers to go down it. So eventually I hope that all pro audio headphones will have at least a little bit of calibration you know, somehow integrated in them. Sam Inglis: And on your website, it states that the X1 calibration processes uses machine learning and also that it's individually calibrated for each pair of headphones. Can you talk us a little bit through how the process works? Rok Gulič: Not in detail but in a broad stroke, we have a tool that can listen to individual pair, so again it's an ear simulator, we put the device under test on it and we run the program which is basically listening to a pink noise and it's then analysing that and creates an EQ to correct it, to fit to what you know, we've set as the ideal frequency response and it does that with extreme consistency which is obviously the most important part when it comes to calibration, because beforehand to do that at scale, we would need to have an engineer doing that, you know, throughout the day which is of course tiring and there's like human factors get in the way as well. So the consistency went up by employing that and also the amount of calculations that are possible with this kind of tools, it's just so much higher that the accuracy of the final result is just, you know, on another level. Sam Inglis: I was interested to see the EQ curves that this process comes up with because unlike some correction programs, they're not highly granular, there's not hundreds of tiny little notches in there, it's just three or four broad and quite shallow tonal shaping cuts. Is that a deliberate choice on your part? Rok Gulič: Yeah for two reasons. So one reason is that the headphones themselves out of the box without calibration are already super flat, so you don't really need to change much or adjust much. That's one side of the story. The other is that we all have different ears and because of that, we have so-called health-related transfer functions that are so popular in many YouTube channels. So what that introduces are little resonances that we all have in different places. So for you it could be 6kHz, for me it could be 7kHz. So now the ear simulator that we used to measure those resonances will have its internal resonance as well. It could be at 6.5, it could be at 8, it doesn't really matter. The point is that if we were going to adjust a frequency response based on the resonance of the ear simulator, so the device that is capturing the frequency response, then we could drastically alter your experience with the headphones because if you are deep is at 6 and we are introducing a boost that at 8, obviously you will feel uncomfortable listening to this, those kind of headphones and that is basically the feedback that we've learned from exploring, you know, online forums with other companies that are doing similar things as we do, not to name them and you know, the air calibration is kind of granular, they go with 10, 15 different you know, bands in there and trying to use very narrow Q factors to really pinpoint specific frequencies and then what happens is that many of the final users do not really like the sound because the frequencies that they're tweaking are not exactly where, you know, the final user experience them. So for that reason as well we're trying to avoid that altogether and we just use these broad strokes of Q factors of 0.3, 0.5. Sam Inglis: That makes a lot of sense, yeah. And going further, I suppose there are some manufacturers now who are making active headphones with digital DSP built into them to perform calibration or other things like virtualisation. Is that a route that you've thought about going down? Rok Gulič: I mean, yeah, we've partnered with Realphones so of course they provide a software that is capable of, you know, running as a system-wide application as well as a plug-in inside those and they do have a variety of different settings available there from room emulation to calibration to different target curve and so on. So obviously it made absolutely no sense to develop that in house since, you know, they've spent the decades doing what they do. So we've partnered with them on this note, yeah. Sam Inglis: But you're not thinking about, at some point for example, bringing that technology into the headphones themselves? Rok Gulič: So you mean like in the harbour, so directly in the headphones? Sam Inglis: Yeah. Yes because I mean, there are some people making active headphones with with DSP in them, like Apple with their AirPods for example. Rok Gulič: Yeah OK, I get it now. Sure it would be possible but the moment you move DSP out of the computer or the audio interface that audio engineers are so carefully selecting, you're doing digital to analogue conversion on a circuitry inside the headphone, powered by a battery or something like that and there's no way to avoid latency. And secondly to get the quality inside the headphone, the circuitry to, you know, do what a $10,000 interface will do, it's just not possible. So in full honesty, we are not really researching that as a viable future. Sam Inglis: And how much difference in your experience does the headphone amp make, especially with relatively low impedance headphones? Rok Gulič: It does a little bit for sure. So for me, obviously you can hear the difference between A class or A, B and D classes, that's like immediate, but in terms of just the detail and the airiness of the sound or the dynamic range and the transient and all these things that, you know, everybody wants to talk about a lot, they get different and I still believe it's kind of subjective to say what is really better 'cause those aren't really nuances and if you are enjoying exploring this nuances then of course it makes total sense to go down this path and explore different types of pre-amplification and see what happens. But in terms just of, you know, usability of our product which is designed and made for audio engineers and artists and so on, you know, you plug them into whatever amplifier have available and they will deliver, you know, more than good enough sound to do your work and that's the goal, yeah. Sam Inglis: So could you improve the listening experience significantly by making a pair of headphones with a matching amplifier as, for example, Austrian Audio did with the composer? Rok Gulič: We probably could and maybe we will someday. I mean, I do have it over there, it's in the dark, a prototype, a prototyping unit that's been developed about two years ago. But the more we learn from the final users from the marketplace is that the amplification for headphones is kind of saturated market and the added value for the final user, for our user is very minimal. So in this regard, or as a disclaimer maybe even, you know, we are in the pro audio industry where efficiency matters where plug and play matters and we don't really go into little nuances too much in terms of, or maybe the way that audiophiles would go to and discuss things. It's just a different use case and we try to stay this course to really truly deliver something that works in the studio, in the sessions as a workhorse, as a tool, not so much as a you know, something that you enjoy obviously, but not really in this audiophiliac kind of way, yeah. Sam Inglis: And it's interesting that you talk like that because most headphone manufacturers span the Hi-Fi market or the audiophile market as well as the studio market and as sort of the general consumer electronics market. If you look at any of the large headphone manufacturers, they'll make a range of products from a few tens of pounds or dollars, right up to thousands of pounds and dollars. At the moment you are very much targeting just the studio market. Do you plan to expand outta that or are you gonna keep that focus? Rok Gulič: No, we are definitely gonna keep that focus. It's just, it's what we do, it's also what we understand and also maybe as a fun fact, we truly deliver or develop our products in collaboration with our users. We have a very strong endorsement program and student program which gives us access to, you know, hundreds of people and basically we learn from them in terms of how they're using these products, what are the issues that they're experiencing, what really matters. So we are kind of skipping the whole technical part in terms of do we need it to be like 30ohms or 50ohms or 200ohms, we just ignore that, which may sound funny but you know, we ignore that and we focus on what are they saying, how are they using it, what are the situations where, when, you know, our product for some reason failed and we learned from that and then designed products based on that. Then the science part of course is done in the lab but we don't really have to have a discussion about it with users because quite frankly, there's like a very little percentage of users that truly understand what a headphone is, how it's made, what you know, all the bits and pieces that go into it. So we really try to keep it as simple as possible for the final user to understand and also to interact with us and you know, give us the feedback that we absolutely need to deliver the next generation of product to these users. Sam Inglis: And given that you're working in quite a niche market then, obviously it's important to you that you have as global a reach as possible that you are able to sell outside Europe certainly and presumably all over the world. It looks like that's becoming more and more difficult thanks to certain developments in world politics. How's that all going for you? Rok Gulič: Well, so far all good. We do still sell most of our products in Europe as well as Japan is like a really strong market for us. And US has been growing in the last year and funnily enough, the UK has been our primary market in the 2017, 2018 when the Brexit happened and it's dropped to, you know, basically off the chart so we didn't even see it in our Excel spreadsheets anymore. But lately in the last year it's getting traction, again even though they're still import duties and all these mass being involved there, yeah, we do sell globally, there are challenges, specifically regulatory challenges in terms of electronic wastes and stuff like that and certification of products and so on. So there is kind of like an overhead burden especially for a small company because we're basically paying almost the same amounts as huge companies do, so we are in a disadvantage in that way. But at the same time, we're super lean, we can, you know, make a move from now to five minutes later so that gives us again the edge to produce something that's cool. And honestly I don't think customers really care about how we deliver those products on which channels as long as it's there, as long as it's possible to get it you know, the delivery should be fast and again the support part I think is extremely important, to get an answer, to get someone on the phone or reply on the email in 24 hours, maybe two days if it's a weekend and get things sorted out as quickly as possible. Sam Inglis: So I guess for a company like yours then there's relatively little value in having a local distributor in a territory, you're often better off selling direct and handling support yourselves. Rok Gulič: Yeah, we did have quite a few test runs with distribution and as it's turned out, we currently only have two left, two and a half which is one for the French market and the Benelux and one for Japan. Everywhere else we kind of terminated the agreements and we just do direct sales. Sam Inglis: Yeah, I think that makes a lot of sense. And do you find that there are different tastes in headphones that, I know you do a lot of research among your users to find out what they like and what they don't like, do those vary with region? Do people in Japan have different preferences from people in the US or in Europe? Rok Gulič: Yes, they do. So we are not researching as in general, but in terms of frequency response alone because that's what we do and that's all we are about. As it turns out, the Japanese language has some syllables that are pronounced a little bit different than the Western languages or the romantic languages and they tend to need a little bit more presence in the headphones in terms of 5, 6, 7kHz region and the regional design it, we had the S4X was kind of welcomed there but really didn't took off too much. Then we launched the S5X which was basically a brighter headphone and we had like a massive boost in sales and the feedback was great, I can finally hear vocals the way I wanted it and then funnily enough, I went to the lab and did comparison with other products that are nicely sold and even made in Japan from Sony for example and those headphones are kind of brittle and bright and very, you know, direct in a way I guess. So there is something in Japan that does demand a little bit more high-end presence in comparison to, for example the Adriatic region, so I'm from Slovenia. Slovenia was a part of ex-Yugoslavia so we are just, you know, an hour drive away from Venice, Italy. But if I would move my research down the Adriatic region to Bosnia and Serbia and so on for some reason they really love bass. It's like 3, 4, 5dB more bass than anything else, anywhere else which is interesting. So again, we are talking about flat frequency response in terms of scientific way, but then we have this ethnicity groups or you know, geo something related things that I don't really know and understand, but there are differences and I can pick that up just by listening to customers from all over the world and I do see patterns and you know, I can kind of get an idea of what the differences are between all of us. But at the end of the day, we have to deliver a product for everyone and this is the nice thing that you've mentioned before with the Realphones and the software part and the calibration, we make them flat in terms of you know, scientifically flat but you can adjust that to your taste if you really need to. If you are really used to, you know, mixing with a lot of bass, of course you need headphones that deliver the scientifically correct signal but you will tend to want to have slightly more bass because you're just used used to it. And the end of the day, the most important part for us and I believe for your Sam as well, is serving the community. Serving in our case, serving our clients, in your case, serving your community with correct information so that they can make, you know, educated decisions. I think that's what it's all about isn't it? Sam Inglis: Absolutely. I mean, if we're not helping people to make the right decisions when they spend their money, then why are we here? Rok Gulič: Exactly. Sam Inglis: And if you're not helping people to make the right decisions when they're mixing, why are you here? Rok Gulič: Exactly, exactly. Sam Inglis: Yeah, it's been absolutely fascinating. So thank you very much Rok Gulič from OLLO Audio, you've been listening to the Sound On Sound People & Music Industry podcast with me, Sam Inglis. Thank-you for listening and be sure to check out the show notes page for this episode where you'll find further information along with web links and details of all the other episodes. And just before you go, let me point you to the soundonsound.com/podcasts website page where you can explore what's playing on our other channels.