Preview : FOCUS Wales 2018 : Oblong / Alffa

As the Husker Dü song Sorry Somehow says, 'Time heals, time goes on and time really flies'. With that information taken onboard, you would want to spend it wisely. How? In his book Outliers, Malcolm Gladwell mapped out the case for 10,000 hours of deliberate practice being needed to become world class in any field; but just go for complete understanding of something, and it can be achieved much more quickly. For example, sixty minutes or so spent at this gig would be more than be enough to fully comprehend the vibrant edge and spirit found in Welsh language contemporary music, even if you wake up every day and unfortunately find yourself to be Rod Liddle.

Bilingual post-punk seers Oblong, tagged as 'fuzzed up shed skronk' in a moment of descriptive genius by Radio Wales' Adam Walton, released their debut album last year. The record - Briliant ... gwd - is dense with 'melodic songs delivered with an insistent, wired, urban rock sound'; a jagged assault of guitar underpinned by powerful low slung bass, an electric maelstrom used to frame blank-sung, desolate lyrics. Utterly and loudly magnificent from start to finish - and, as you'd expect, live Oblong are a sudden, raw onrush of explosive pent-up energy. A follow up album is being recorded, and this Wrexham date is the furthest flung of a Welsh spring tour that also takes in Swansea and their hometown of Llanelli.

Alffa are from Llanrug; a duo as far as possible as the laws of physics will allow from the seventies mental image of Peters and Lee that the term might spark in an older mind. The elemental drum, vocal and guitar parts their songs are built from mean Alffa are rudimentary by design - but also hard-edged, dazzling and brilliant; demonstrated by the recent Radio Cymru session posted to their SoundCloud page. If you have any doubt, then listen to the slow-paced blues of Tomos Rhys from that set (see below). When they were first added to the FOCUS Wales bill we said they are a band worth walking barefoot over nettles to see.

Saith Seren is the perfect place for this pairing - a compact venue that can contain and amplify the energy of the music, and make listening a physical experience.

Alffa take the stage at 9.50pm, Oblong at 10.40pm, on Saturday, 12th May. Before they play Quiet Marauder, Al Moses, White Ether and Brook will entertain at the same venue; if you want to settle in one chair for the evening, it is a great line-up from top to bottom.

To quote Bob Mould again - 'Now I guess it's your decision, now you decide' - but this is the promise of an hour of unmissable and stirring mayhem, fit to excite anyone with a pulse.