The best thing about Islet is that their first notes can make a Joy Collective writer break off a conversation with a shout of “I FUCKING LOVE THIS ONE!” before rushing to the front of the stage.  The best thing about Islet is that every member of the band is the best one.  The best thing about Islet is that you can’t take your eyes off any of them because they’re about to do something brilliant – wander into the crowd, switch instruments, howl wordlessly off-mic.  The best thing about Islet is that they actually play pretty uncommercial music, but with a force and presence that makes beaming converts even in early evening support slots.  The best thing about Islet is that you can feel them growing from something that “works best live” into a genuinely thrilling band without having to change a thing.  The best thing about Islet is that when there’s two of them drumming together it sounds like six people drumming.  The best thing about Islet is that the two drummers knock sticks together during solos.  The best thing about Islet is that they can work rooms the size of upstairs at Clwb and force people to get involved, and that you know they could easily do the same for bigger rooms, or festival crowds – wheeling around, spilling drinks, engaging with people.  The best thing about Islet is that Alex ends the set drumming on my back.  The best thing about Islet is the room full of grins afterwards.  The best thing about Islet is that they keep getting fucking better.

The positive response afforded Islet – even the baffled faces are smiling – gives you a feeling of cautious optimism about how Gruff Rhys and Tony Da Gatorra will be received.  Last night’s show, albeit the second to be announced and thus possibly attended by more floating voters and casual SFA fans unfamiliar with Gruff’s more out-there whims, apparently endured disappointed muttering and walkouts as it became gradually apparent that there wouldn’t be so much as a Candylion, let alone any hits for old time’s sake.  Whether or not tonight’s crowd were more savvy to the backstory behind Gruff’s link-up with the Brazilian TV repairman and home-made instrument enthusiast, there’s an air of genuine affection for our host’s typically endearing, faltering introductions and his new-found brother in rhythm (“No notes. Only rhythm”) with his universal sounds of self-expression and personal protest.

In any case, it’s not like the parameters for the evening aren’t set from the off.  Gruff’s intro explains the basis for the collaboration, the linguistic barriers the two face in working together and a little of the socio-political background to Gatorra’s homespun, almost outsider folk jams about inequality and corruption in his home country.  The two take turns to perform their songs from The Terror Of Cosmic Loneliness, each improvising on guitar, the unique hybrid Gatorra itself and vocals to back up the other.  With some noticeably wincing at the chattering, occasionally arrhythmic patterns of Da Gatorra’s instrument, Rhys’ ‘In A House With No Mirrors’ is a relief, many grasping for more coherence along those lines. 

As Da Gatorra embarks on increasingly lengthy and rhythmically complex condemnations of injustice and calls for peace, hammering away at the buttons and dials on his instrument, Rhys tapes agit-prop soundbites (Violence! Elitism! Impunity!) to the backdrop and looks on with a beatific grin before resuming his own contribution.  It’s often hard work, to be fair, but the overwhelming feeling half an hour or so into the set is not just that actually, this is great (it is), but that this is possibly the largest mainstream (ish) crowd ever to witness music this wilfully difficult, this out there, certainly in Wales.  And you start grinning too.

But while it’s tempting to view the playfulness of the cultural exchange – the Power Ranger helmet, the Wolfie Smith slogans, Gatorra’s headband proclaiming ‘PAZ!’ and his general look of Brian Hibbard doing Spinal Tap – as a conceptual joke on Gruff’s part, both men are clearly not only enjoying themselves immensely but deadly serious about the music they’ve made together, the ability of English, Welsh and Portuguese-speaking men to collaborate with no shared language other than sound and a try-anything attitude.  Those willing to share in the spirit are rewarded, if you need to see it that way, with a run through Candylion’s ‘Gyrru Gyrru Gyrru’ and, thrillingly, the old Ffa Coffi Pawb tune ‘Valium’.  The point, though, is maybe that a few minds opened to the possibility of what music can do to reach people.  “Bloody hell”, muses one chap in the gents’ afterwards, “and I thought the first lot were weird!”.  As a baffled but happy assessment of the evening, that’s hard to top.