“If I would play guitar how I have been taught, nobody would want to listen to it”, Miloš Karadaglić tells me. “If you would do everything ‘correctly’ at all times, it would never go that extra mile. When I play, I always feel like I’m going to so many danger zones and so many hot spots... it’s like a car race, there are always these curves, little twists and turns that really make your head spin.”

The previous evening, Miloš – he usually drops the surname – has been on one of the more high wire assignments of his career: playing the world première of Joby Talbot’s new guitar concerto Ink Dark Moon in front of 4,000 people at the Royal Albert Hall. How did the concert go for him, I ask, having confessed that the acoustics were less than ideal from my seat position?

“For us on stage, it was amazing. Actually, the Albert Hall just has the most special atmosphere of any concert hall I know. They are really trying to work on the acoustics all the time there – but you know, as a performer, wherever you play, you just have to go out and give it your all. I was on cloud nine, really. I absolutely love the piece, I love working with Vedernikov, the BBC Symphony Orchestra is such a great group of players and really wonderful people. Rehearsing with them and giving life to something completely new with them and Joby was a first for me. It’s a process that really compares to nothing else.”

Guitar concertos are a rare breed, not least because the guitar works so differently from the orchestral instruments with which most composers are considerably more familiar. Like the piano, the guitar is polyphonic: it can play melody, bass line and fills simultaneously (orchestrations by the great bel canto composers have been derided as being like “a big guitar”). Unlike the piano, though, the classical guitar lacks sustain, requiring the technically difficult use of tremolo to substitute for it. It’s also quiet, which makes it hard to achieve the right balance, making the guitar audible without sucking all the energy out of the orchestral performance – that’s something, Miloš says, that very few conductors know how to do.

It was therefore important that he worked closely with Talbot from the beginning of the composition of Ink Dark Moon. “We spent quite a lot of time where I was showing him examples of things that I love to play, when I was showing him what’s possible and what’s not possible on the guitar, because it’s one of the hardest instruments to write for. We spent a lot of time going through examples of guitar pieces, maybe some other concertos, not just guitar concertos but the concertos I always enjoyed and liked playing. And the whole time, the idea of this piece was that it would really push those boundaries of what we know is possible with the guitar concertos and guitar.”

The process was disrupted when Miloš suffered a career-threatening hand injury, which forced him to stop playing for many months, making it impossible for him to be 100% involved in every note in the way he had anticipated. Perhaps, he considers, that was a blessing in disguise: “I gave him very clear instructions. I said you need to write anything you want and anything you hear in your head, and then it’s my job to make it work.” His arranging skills, learnt as part of his course and mandatory because of the limited repertoire written originally for classical guitar, proved invaluable. “When I’m given a piece, I’m really good at making it work in the sense of bringing out fingerings and lines and melodies and things that sustain. I’m always very attracted to the polyphonic aspect of the guitar: it’s a crime if you have an arrangement and you have to cut a line just because the fingering doesn’t work.” Miloš is also enthusiastic about the general shape of Talbot’s writing: “very often, the orchestra is like a resonating board to the guitar, so the idea comes out of the guitar then the orchestra picks it up and it kind of spreads it around. I really love that because it gives you that amazingly impressionistic feeling of the music.”

Composer and soloist were attracted to each other from very early on, with a true feeling of being kindred spirits. “When I heard Joby’s music, I felt that our aesthetics were so similar, and that resulted in the most wonderful friendship and in the most wonderful collaboration. His sound world and language and imagination is so incredibly poetic and he’s not scared to be melodic or tonal, and guitar is such a harmonic, tonal instrument that if you try to write against that, I think it doesn’t always work.”

I ask about amplification – always a thorny subject for classical guitarists. For solo recitals, Miloš plays acoustically where possible. “I have played in concert halls in Japan which have 2,200 seats, without a penny of amplification. I love playing loudly and I love projecting and I think it brings something new to the music. Suntory Hall, or the Philharmonic Hall in Osaka, which is arguably the finest concert hall in the world, it’s just electrifying when you have those places. But you know, we don’t always have the luxury of that, and when we don’t, we simply need to think about the people who are paying for the tickets.” When playing concertos, however, Miloš thinks that “playing without amplification would be suicide – it’s just not possible”. And even with amplification and with the most famous of guitar concertos, Rodrigo’s Concierto de Aranjuez, he says there are limits to what both listeners and performers and listeners can expect: “The key is to understand that when there is a tutti in the orchestra and guitar is playing with that, that guitar is in those moments part of the ensemble. We get our melody lines, we get our cadenzas, we get our scales, we get our exposed moments, but there are moments when we are not so exposed, and in those moments, it would be unnatural to expect that we are still above everyone else.”

Unusually, his favourite part of the Aranjuez is the third movement. The reason that people consider it the weakest point of the concerto, he argues, is that most people play it considerably slower than the terrifying tempo of 164 marked in the score. “If you play it at the speed that’s been indicated, it just turns into the most effervescent, exciting piece of writing, with lines running from one string to the other in the guitar and scales and everything. You can bring it to a very sparkling ending to the piece, after that very thoughtful and sombre second movement.”

The sheer difficulty of playing that third movement at full speed requires intensive rehearsal. “If I haven’t played Aranjuez for a while, I need ten days. I'm being very studious and precise and making sure that every accent is in the right place and everything is organised. The closer you come to the performance, it’s really like you are slowly aggravating the bull, because the moment you come and walk onto the stage to play it, you need to be so bound up in order for it to work. Practising something on your own is one thing, playing something for a few friends is another thing, your first rehearsal is another thing. In performance, you forget about anything that happened before: don’t walk out on stage thinking OK, I have to remember this, I have to remember that. Because if you’ve done your work beforehand, then when you are on stage, it’s just going to be dynamite.”

Miloš recognises that his injury happened simply because he was overdoing it. “When you’re bringing out a recording every year and you’re playing 100 concerts a year, you are doing promotion every day, there are literally not enough hours in the day, and as a serious musician, you are not going to just give a half-baked performance. I injured myself just because I did not understand that there is a limit on how far that can go and that being human is also no shame. When I hurt my hand, I just used my fingers too much.” But he firmly takes Nietzsche’s line that what does not kill us makes us stronger, to the point where he says that although it was an intimidating experience, he is grateful for the self-awareness that the injury brought him. “I feel that my playing is better than ever, that I’m so at one with the music that is in my hands and that really, the best music-making is to come.”