Frédéric Sanchez is not a DJ - even if he has been soundtracking major fashion designers' catwalk shows for nearly 25 years. "I've never been one," he says by phone from his holiday in Normandy, as seagulls squawk in the background. "I've always considered what I do as artistic." And, it turns out, he wasn't always that into fashion either: "I'd always been a music lover," he says, "but wasn't really interested until I saw people like Peter Savile doing both Factory record covers and catalogues for Yohji Yamamoto. I'd always liked it when different artistic disciplines mix - and then I met Martin." That was in 1988, and Martin was Martin Margiela, and the result was Frédéric providing the music for the designer's first ever show. "That moment laid the foundations of my work," he explains. "I was inspired by how experimental films were edited and how the sound was worked on as much as the image. I'm not interested in just sticking some background music on; it's about creating a signature, something that really belongs to each house."

Since 1988, Frédéric has moved from maison to maison, working with a who's who of fashion. "My collaborations with most of them are really long - almost 18 years with Marc Jacobs - so I've really participated in the artistic aspects of their careers," he says, going someway to explaining his longevity in the face of fashion's permanent desire for the new. "But then, for me it's not really about working for big brands; it's about working for designers, people like Miuccia Prada - who work for their own companies. There's a laboratory, R&D side that really interests me." In fact, he says, he doesn't even really look at the clothes: "I talk a lot with the designer and then together we create sounds that provoke images for people during the show. It's about creating a décor - a physical atmosphere that works on the senses, like a perfume."

We asked Frédéric to compile a playlist exclusively for O: by Tank readers, which you can listen to via app. "I've put together a selection that's pretty personal," he says, "I wanted it to be poetic, so I chose someone I've always adored: Richard Jobson. I love his literary references - Marguerite Duras, Jean Cocteau and Jean Genet - which are mine, too. I also like really minimalist electro: so there's a kid called Ben Frost and stuff by Alva Noto with Ryuchi Sakamoto. Then there's the classical with Satie, Wagner and Strauss. So I've mixed up all these influences to create a selection that's really European and also tells my own life story. It's about my taste, the tastes I've always had."

What ever happened to authenticity? This London quartet's new single sounds like they're aiming square for the badlands of Wyoming for years. There's the rolling country drums, the twanging country guitars, the vague country twang of the singer.

But they are so sincere about their inauthenticity, it's done with such a straight face, it's almost hard to fault the finished product. Sincerity about inauthenticity feels like a neat emblem for modern music.

Ty Segall has got such an intense workrate. His discography reads at a staggering 47 records of various hues, EPs, LPs, splits, collabs and compilations. For all the skuzzed out stonedness of his music, he must be taking something that gives you a bit more energy than the herb. The most apt comparison is a of Ty as a slacker Captain Beefheart, channeling the weirdness into the nihilistic thrill of guitars.

After a recent dip in form with 2011's Goodbye Bread, where he tried to make his music more expansive and slightly poppier, his past three records have been pitch perfect, sweltering psychedelic punk rock, aiming directly at small sweltering club shows, with sweat oozing out of the ceiling and spilt beer everywhere.

Ty Segall - "The Hill" by Drag City