We talk to the new breed who are turning on, tuning in and dropping out, and hear the verdicts of older heads Sonic Boom, Wayne Coyne and Kaleidoscope

Psychedelia is everywhere right now. There are original psychedelic bands making comebacks, and legions of young psychedelic bands, from Toy and Temples to Tame Impala. There is psychedelic celluloid, with an imminent biopic of guitar visionary Jimi Hendrix, starring André Benjamin of OutKast as the psychedelic dandy. There are psychedelic festivals, both in the UK and abroad, designed to showcase psychedelic talent, new and old, from across the globe. But it's not a surface culture of trippy hippies with flowers in their hair spreading the message of peace and love like we saw in 1967; it's about pockets of activity in every country, micro-scenes with a shared consciousness making contact via the web.

"What makes this version of psychedelia unique is the global nature of it," says Craig Pennington, organiser of the Liverpool International Festival of Psychedelia, which takes place over two days this weekend. "They've been brought together by the internet," he says of the thousands of zealots who will be converging on the city, and the dozens of acts on the bill. "We've got bands from Santiago in Chile and Mexico City alongside bands from LA and Denmark. You wouldn't have been able to have this in any other period in history. It's like a global psychedelic village."

The festival comprises "two days of worship" of the "weird and warped", with "mind-expanding visual delights" and music from guitar-bass-drums outfits stretching the possibilities of the standard rock band set-up to electronic artists. There are so many acts that it raises the question: is all music, if it's doing its job right (experimenting, blowing minds), psychedelic?

"If it's really powerful and strongly emotive, it's psychedelic," decides Pete Kember, who as Sonic Boom has been exploring the outer limits for almost three decades, first with Spacemen 3, then as Spectrum and EAR (Experimental Audio Research), and more recently as producer and mixer for MGMT and Panda Bear of Animal Collective. So prevalent is psychedelia in 2013, Kember jokes, he has been banned from using the term. "It crops up in so many different ways, with all the bands we play with, that my wife, who manages me, has imposed a fine system for inappropriate use of the word."

Kember sees a distinction between psychedelia as a "lazy catch-all" for period fetishists who recreate the look and sound of 1967-68 and psychedelia as a broader encapsulation of the innovative. He singles out the Beatles' Tomorrow Never Knows as an example of early psychedelia that will have "floored" listeners when they first heard it, and suggests the current bands who might be making equivalent leaps into the sonic unknown today.

'My Bloody Valentine are psychedelic! Gustav Mahler is psychedelic! Any musician not playing by the rulebook and going inside their heads is psychedelic' – Wayne Coyne

Wayne Coyne of The Flaming Lips. Photograph: Joey Foley/Getty Images

"Indian Jewelry and Peaking Lights at full tilt," he offers. "It has become a far wider term, and it can apply simply to musicians who rewrite the rules, so I would say Aphex Twin is 'psychedelic', as are Hookworms, Wooden Shjips, Vacant Lots, TTotals … The difference between Goat and Clinic is vast but their fans would probably argue that they're both supremely psychedelic. The same goes for Animal Collective and Panda Bear."

Flaming Lips frontman Wayne Coyne agrees psychedelia is wherever you find it. "What I always liked about punk or post-punk was it was freaky," he says. "I'd be like, 'Joy Division are psychedelic!' and people would be like, 'What the fuck are you talking about?' They might not have been that Butthole Surfers or Grateful Dead type of psychedelic where you're a weirdo with long hair who takes drugs, but in terms of being dangerous and 'far-out' they certainly were. My Bloody Valentine are psychedelic! Gustav Mahler is psychedelic! Any musician not playing by the rulebook and going inside their heads is psychedelic."

Coyne and Kember both note the difference between US psychedelia, which as typified by the Dead is looser, more bluesy and based on lengthy exploratory jamming, and the uptight, tense UK variety, of which Syd Barrett's Pink Floyd are prime examples.

"English psychedelia is more influenced by the European avant garde, by Stockhausen, Varèse, music-concrete," considers Kember. "The American stuff comes from a bluesy rock'n'roll base." Coyne, whose band covered the Floyd's The Dark Side of the Moon in its entirety, enjoys aspects of both. "I like loud, freaky, drug-damaged music, and the Dead's music to me is just dudes being mellow getting stoned on acid. I relate more to the Pink Floyd type of psychedelia but I relate more to the Dead lifestyle. I want to hang out with the Dead but secretly listen to the Floyd."

Everyone interviewed for this article agrees psychedelia is about more than just music. As Pennington puts it: "Psychedelia is a mindset and a viewpoint more than it is a sound." James Bagshaw of Temples, recently hailed by Noel Gallagher as "the best new band in Britain", however, considers it crucial to take that sound somewhere new. "Whether it's a Motown rhythm or a Joe Meek production element, we always try and bring it into the 21st century," he says. "We don't ever want to be a pastiche." Clinic's Ade Blackburn doesn't accept that the best of the current exponents mimic the past in the manner of certain previous psych revivals, and worries the term is misleading. "They don't slavishly copy the 60s in the way that bands from the 80s Paisley Underground did. And I'd say it's more that people are making imaginative music and have ended up with the tag 'psychedelic'." Conversely, Andreas Pallisgaard from Denmark's Pinkunoizu acknowledges the "retromania" that is "rife in western society" and can detect in many current psych recordings a "longing for the aura" of the era of analogue music. "It's funny how we use modern technology to create something that sounds old," he says. "Even in music software you get options to manipulate your sound via plugins to make it sound like old tape, broken tubes, crackling amps, old plate reverbs and so on. This is really happening now."

Reading on mobile? Listen to our psychedelic Spotify playlist here

Christian Johansson of the Swedish band Goat – whose World Music album is regarded as a latterday psych classic, with its nods to krautrock, funk and folk – takes a different tack, realising the need for "spirituality and mind-expanding music as a reaction to our materialistic and individualistic world"; he considers it part of "an evolutionary process".

More rooted in the real are Leeds outfit Hookworms, for whom "energy and intensity are more important than anything". According to band member MJ, while psychedelia has always provided an alternative to harsh reality, Hookworms' noise-outs are an escape from that form of escapism. "We don't just stick a delay pedal on and play guitar for 30 minutes," he says. "We look at the music through social values and ethics." For Pallisgaard there's a compromise: "The persistent critique of psychedelic music is that it is apolitical and escapist. Really it's about a longing for something otherworldly, a transcendent state of mind."

'We were hitting DMT so we could check the music out. It's a 15-minute trip with no real comedown so it's easy to use in the studio' – Pete Kember

Pete Kember of Spectrum onstage in Barcelona. Photograph: Jordi Vidal/Redferns

When asked whether drugs are a requirement for the enjoyment or creation of psychedelic music, all the newer bands reply in the negative. MJ of Hookworms says no to narcotics and yes to biscuits. "People ask what's my favourite drug, and I say Chocolate Hobnobs," he deadpans. "I see more interesting diversions in music from totally focused people, not ones who are wild-eyed."

Pete Kember doesn't necessarily agree – not surprising given Spacemen 3's motto of "Taking drugs to make music to take drugs to".

"With Spacemen 3, we tried to make druggy, droney music, and once we'd recorded it we would give it the acid test – which was taking acid to it," he recalls. "Same as when I made the Spectrum album Forever Alien – we were hitting DMT so we could check the music out. It's a 15-minute trip with no real comedown so it's easy to use in the studio. You have to be a bit of a psychedelic stormtrooper, because it takes you straight into the deep end of the trip within the first minute. And then you get the most intensely sublime and beautiful experience I've ever had through drugs. It's an awe-inspiring rush of psychedelia."

It's been a long, strange trip for the genre that, explains Kember, began variously with America's 13th Floor Elevators, electronic composer Morton Subotnick and the BBC Radiophonic Workshop's Delia Derbyshire. Peter Daltrey, leader of Kaleidoscope – purveyors of a distinctly British, almost creepily pretty, fey and twee strand of psych that drew on music hall and fairytales – was there from the off. He remembers the day – and it was that abrupt – when the world went from monochrome to psychedelic.

"I remember walking down Carnaby Street and where before the streets were dirty and grey, suddenly it metamorphosised and the atmosphere was fantastic," he says. "We didn't realise it, but we were living in the 60s."

How does he feel to be feted by twentysomethings wearing the sort of regalia he would have purchased 45 years ago from Granny Takes a Trip?

"Charming," he says, as Kaleidoscope's first gig since the 1970 Isle of Wight festival approaches, delighted at invitations from musicians a third his age to collaborate. "I'm having the time of my life."

This is what Craig Pennington finds so appealing, and what moved him to start a festival in the first place: the pleasure of community provided by psychedelia in an increasingly atomised world. "Psychedelia is a passport, a kindred connection you can have with people on the other side of the planet," he says. "It's the most romantic thing in the world." The Liverpool International Festival of Psychedelia takes place Fri & 28 Sep. Kaleidoscope play the Assembly Hall, N1, on 17 Nov

Psychedelic landmarks

The Beatles – Tomorrow Never Knows

The first major psychedelic record, give or take the Byrds' Eight Miles High.

Pink Floyd – See Emily Play

So psychedelic that, within a year, writer Syd Barrett had left the band.

The Doors – Light My Fire

Jim Morrison et al break on through to the other side.

My Bloody Valentine – You Made Me Realise

Kevin Shields's reinvention of the guitar was psychedelic.

The Flaming Lips – Psychiatric Explorations of the Fetus with Needles

The Oklahoma band's titles alone are pure psych.