• A ‘Slack Thwack’ tuning •



Use the ‘slack thwack’ to access the bass guitar register in your lead playing (well, all but the very lowest 5 notes of it). Tuning the 6str right down to A – downwards a perfect 5th – will bring a strange buzz…but opens up some unique textures and grooves. Some guitars will handle it better than others – give it a try on yours!


The huge width exceeds that of many 7-string guitars, and the low bass-string separation is somewhat reminiscent of a harp guitar. And to extend the basic idea to other keys: tune the 6str down to your chosen root and see where it leads. Some real jam freedom to be found here.

Pattern: 12>5>5>4>5
Harmony: A9(sus4) | 1-1-4-b7-2-5




Antonio Forcione’s virtuoso nylon-string trickery on Acoustic Revenge is hands-down the best modern showcase of the slack thwack (“I use extra hard tension on the bottom E…it still has to hold”).


Also used on Bangers + Mash (Jonny Greenwood), Caligulove (Josh Homme), No One Loves Me and Neither Do I (Them Crooked Vultures), Citizen Erased (Muse), Moor (Every Time I Die), Sorceress (Opeth), Strat Riff (Bluffalo), and Stella by Starlight (Jeffery Matz).


(And for a few highlights from the actual harp guitar – which long predates the advent of recorded sound – try out George N. Dudley, Pasquale Taraffo, Alfred Karnes, Michael Hedges, Muriel Anderson, Andy McKee, Antoine Dufour, and Jamie Dupuis.)


  • Acoustic Revenge – Antonio Forcione (2000):


6str 5str 4str 3str 2str 1str
Note A A D G B E
Alteration -7 0 0 0 0 0
Tension (%) -55 0 0 0 0 0
Freq. (Hz) 55 110 147 196 247 330
Pattern (>) 12 5 5 4 5
Semitones 0 12 17 22 26 31
Intervals 1 1 4 b7 2 5
  • See my Tunings Megatable for further such nerdery: more numbers, intervallic relations, comparative methods, etc. And to any genuine vibratory scientists reading: please critique my DIY analysis!


—Associated tunings: proximities of shape, concept, context, etc…

  • Drop D (this with 6str +5): the classic low drop
  • Drop C (this with 6str +3): another big low drop
  • Equilibrium: featuring an even slacker 6str


—Further learnings: sources, readings, lessons, other onward links…

  • Slack thwack chat: discussion on Harmony Central, including electric stringing suggestions (“the beauty of standard drop A is having octave strings right next to each other”)
  • Antonio Forcione: read this interview with Sound Rebels, and this one with MusicRadar (with an accompanying guitar lesson)- and watch this short interview clip of him chatting and playing (“it’s not about technique, it’s about…the capacity to connect when you are playing, being totally absorbed…”)


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rāga: ‘that which colours the mind’

George Howlett is a London-based musician, writer, and teacher. I play guitar, tabla, and santoor, loosely focusing on jazz, rhythm, and other global improvised traditions. Above all I seek to enthuse fellow sonic searchers, interconnecting fresh vibrations with the human voices, cultures, and passions behind them. Site above, follow below, & hit me up for…


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Dedicated to Nigel Tufnel – a true tuning connoisseur

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