The quality of its sound and its usability. On the whole, the Xone:92 is faithful to the source sound, and flat. These days there are more superior mixers in terms of functionality, but I'm most used to the handling of the Xone:92. I like the combination of Urei and Dope Real isolator as well. But I generally don't mind which mixer I end up using, because each mixer gives a different kind of positive feeling when you mix two tracks together. Up until 2010, I mainly played vinyl, but with the release of the Pioneer CDJ-2000s I began using CDJs because the sound quality was noticeably better [than the older models].Now I mainly use USBs but also play vinyl depending on the situation. Recently at Rainbow Disco Club I played a house set back-to-back with The Black Madonna—I used vinyl on that occasion. Sometimes it's tricky to DJ when the low-end travels inside the booth, but the foundations of the booth were solid, and there wasn't any interference from the outside speakers. Playing house tracks, I thought I could better create the groove I wanted with vinyl, so that's why I chose to play with them.It's down to convenience and efficiency. You can take a lot of tracks with you, and sometimes there are venues that don't cater properly for DJs who play vinyl—with USB you can adjust to most circumstances. I was a little hesitant about CDJs in the beginning, but as I said, with the arrival of CDJ-2000s the sound output was drastically different to earlier models, and I was satisfied with the sound quality. Also, up until then, I thought you could only create a groove with vinyl. I used CDJs before then and couldn't create the groove I had in my mind. This changed completely with the CDJ-2000. The CDJ-2000NXS2 has evolved even more, with better sound output and handling.I make a point of bringing a well-balanced collection of tracks so that I can respond to the crowd. And because I can take a lot of tracks on the USB, I divide the tracks into categories of my own—if something is more acid-like or deep and so on I can immediately find the tracks I want while I'm playing.That's why the EQ is so important. I think it's important to remember how each track sounds when it's played out. How much you understand each track before you put your DJing into practice is key.When you play across a lot of genres I think it's more fun to do short mixes. But on the other hand, there's a fantastic feeling that comes from layering sounds. So I do long transitions when I play techno, focusing a lot on the layers between sounds. With the EQ, I listen to the sound output of a given space, decide how to control the EQ, and think about how it would feel the best. Of course, you should really understand the character of the two tracks you're mixing before you start to build satisfying layers.I recently played for around five hours in Hamamatsu and Okinawa. The longest set I've played is around 12.5 hours, but I think the three-hour mark is the best for me.It's easier to shape the set and make it flow. I try to express myself—by doing things like steadying the groove or introducing a beautiful melody—while creating a narrative at the same time. But speaking of short sets, I recently played at Boiler Room for only an hour and I think I managed to build something within that time.I try and find the middle ground. You should think about your set in relation to the general mood of the night—you can't ignore the audience completely and start a set with a pre-planned track.You also shouldn't be totally controlled by the audience, but even if you want to take it in a certain direction you should follow the vibe of the floor. Although sometimes you might end up in a situation where the audience is satisfied but perhaps you're not. But it's always a great feeling if you see happy faces in the audience at the end of the night.I constantly check the facial expressions of the crowd in order to communicate with the floor. There are different expressions depending on whether people are tired or having a good time. I'm always observing the reaction of the audience when selecting tracks, then choosing whether to build it up or calm it downIt depends on the venue, but sometimes I check the reaction of the people around the sweet spot on the dance floor. And, of course, the expression of the people right at the front, too. The track selection changes depending on the size of the venue. It's absolutely crucial that you respond flexibly to each situation.Within the first four tracks, I'll try and grasp what the audience wants. If I get the feeling that I can follow the image I have in my mind I'll try that approach. But if I get the sense that it's not that kind of night I won't force that image onto the audience, and I'll switch to blend in with the situation—I don't want to ruin the atmosphere of the party. So usually I spend the half hour before my set assessing the atmosphere of the floor. For the middle segment, I'll try to build an atmosphere in which the dancers can really focus on the music and loose their sense of time.And for the end, if I'm the last on the bill, I'll be thinking about how best to guide the audience to a steady landing. When everything clicks there's a certain harmony with the audience and I don't even have to think about the next track. If there's another DJ waiting to come on, I'll try and select an understated track to make the transition easier for them.Normally I'll try and match the style or groove of the previous DJ as much as possible. But if it feels like I should bring my own personality to the fore I sometimes change the flow completely. I might even stop the sound before I start my set. In Japan I'm often billed at festivals after acts like [the hip-hop group] Tha Blue Herb. I get a lot of bookings from parties unrelated to techno, which I'm actually really pleased about. If I'm lucky enough to get booked for these kinds of events, it means there's an opportunity to show techno to a completely different audience.I've also played alongside DJ Krush a number of times, but rather than select hip-hop tracks I thought about a selection based on what I think hip-hop audiences might find interesting.Even if the BPM is out of sync when I'm mixing, for example, I'll try not to panic too much. The important thing is to make a quick recovery. And this ability to recover can only be learned through experience. I've made a lot of mistakes over the years, but have also developed the mental strength to recover quickly. There are definitely times when you completely misread the audience with a track you thought was right on-point. But it's important to make a recovery when this happens.It's also nice to take risks because the tension you have in your fingertips when you're mixing, knowing you might fail, always translates to the audience. Like the time at Rainbow Disco Club I mentioned earlier—the wind was so strong but I still chose the risk of the needle skipping because I believed vinyl would be better for that situation.Take the sync function on CDJs, for example. Don't use it because you can't mix or because you find it easier. Since these functions exist I think it's up to us to find new techniques that are only possible by using them. By doing that, you'll create tension.I make adjustments to the EQ to match the sound output. The same goes for my use of the faders when I'm mixing. The most satisfying frequency range differs in each venue, so it doesn't mean you get more impact just by diving into the low-end. You sometimes have to subtract to make maximum impact. The use of the EQ in this way is fundamental to DJing, and I think the most important part. The ears must feel comfortable, even after a long period. Once I understand the characteristics of my tracks, and the way the venue sounds, I try to figure out the most satisfying way to mix. To understand this, I think experience is the most crucial factor.Martial arts—which I was doing while I had a period away from DJing—has helped me a lot with this. In martial arts you're not only thinking about the reaction to an initial move, but also at least two steps ahead. This mentality has actually come in handy for DJing. I'm always conscious of what I'm playing up to around three tracks ahead, but also have an image of where I want to be in 30 minutes' time. But the situation of the audience and the space is constantly morphing, so I also don't force myself to push through with this image. There's of course no audience when I'm making a mix for podcasts or CD mixes, so I can bring together a set where my trajectory is steadily guided towards my goal.My favourite DJs have a sense of rawness. You can impress as a DJ without having very much skill, or you can be technically precise but have no heart. A few years back the needle of Donato Dozzy's turntable jumped during a set at Labyrinth, and I was watching thinking, "Oh crap, the needle skipped. What are you going to do, Donato?" But he made a brilliant recovery. I'm inspired by these moments, too. And when you think about why that is, I think it's because there's a tension and physical immediacy to something that's being controlled by human beings. Other than that, it depends whether that person is able to acquire his or her own unique style. These are the most important points.By mixing something as a DJ, you attempt to transform the enjoyment of a song beyond that of its original form. The strength in keeping this kind of personal approach close to your heart is what's important.