Keira Kenworthy: The Mistress of Groove on Rotosound Swing Bass 66 Strings

From nu-metal teen to internationally gigging session bassist — meet one of the UK's most exciting young players.

“I definitely rate Andy Fraser as a phenomenal bass player.”

— Keira Kenworthy

“If you were to think of string companies, I think the most revered is Rotosound.”

— Keira Kenworthy

At Rotosound, we’ve always believed that great strings belong on every stage — not just the famous ones. That’s why we’re thrilled to shine a spotlight on Keira Kenworthy, a UK-based professional bassist whose formidable groove, genre-spanning versatility, and no-nonsense approach to the instrument perfectly embody what we stand for. From session rooms to international venues, Keira has made our Swing Bass 66 strings her string of choice — and we sat down with her to find out why. Whether you’re a working bassist searching for your next set of strings, or simply a fan of phenomenal bass playing, read on.

Who Is Keira Kenworthy?

Keira Kenworthy is a professional bass player, content creator, and — as she’s quick to tell you herself — the self-proclaimed “Mistress of Groove.” Based in the UK, Keira has built an impressive portfolio of session work and live performance credits across a range of bands and projects.

Her current live and recording affiliations include Red Giant, the Troy Redfern Band, JoanOvArc, and Syteria. She is also a member of Back:N:Black, an all-female AC/DC tribute act based in Switzerland that has taken her across Europe — Germany, the Netherlands, Scandinavia, and beyond. On top of that, she has been involved in a women’s charity music project called The Muses, a collaboration with Italian actress Valeria Altobelli.

“I’m very lucky that I have managed to gig internationally,” Keira says. “I’ve played Thailand, Europe, Scandinavia — although I’ve never yet performed in the United States — I’d love to perform in America, and I’d love to perform in Japan.”

A Family Rhythm: How It All Started

For Keira, music was never a choice — it was the air she breathed growing up. Her father was the drummer for British heavy metal band Raven, meaning a deep connection to rhythm and the rhythm section was instilled in her from birth. With bass guitars a constant fixture around the house, it was only a matter of time before she picked one up seriously.

“I started playing music in my mid-teens,” she explains. “My dad used to be the drummer for a heavy metal band called Raven. So straight away, that association with rhythm and the rhythm section came from my dad.”

That mid-teenage spark quickly grew into a dedicated pursuit of the instrument — one she has never let go of. She went on to study at Leeds College of Music, using a notoriously challenging bassline as her audition piece (more on that below), and has been playing professionally ever since.

Influences: From Jaco to James Jamerson

Keira’s list of bass influences reads like a masterclass syllabus. She cites James Jamerson, Jaco Pastorius, Carol Kaye, Les Claypool, and Victor Wooten as direct inspirations. Her musical touchstones extend to bands including Frank Zappa, Deep Purple, and Free — the latter putting her firmly in the camp of those who rate Andy Fraser as one of the most underappreciated bass players in rock history.

Crucially, it was her father who pushed her beyond the confines of rock and metal. His encouragement to study jazz fusion and soul & R&B masters like Jaco and Jamerson opened Keira’s ears to what she describes as the “feel” of music — something that has defined her playing ever since.

“You listen to the bass lines of jazz fusion and soul R&B and you think — they sound amazing, but there’s also a lot of technique that goes into them,” she recalls. “And one of the biggest things, when you listen to those styles, is you pick up on the feel of the music. It sounds wonderful — very warm. It gives you sort of an emotion when you hear those basslines.”

This revelation led her to tackle Jaco’s “Come On, Come Over” as her first foray into that style, followed by the fiendishly complex Norman Watt-Roy bassline from Ian Dury and the Blockheads’ “Hit Me With Your Rhythm Stick” — which she later used as her Leeds audition piece, and which earned her a compliment from Watt-Roy himself when she met him at a Wilko Johnson performance.

“He said I was one of the few that actually did it correctly,” she says with evident pride. “I’m really pleased about that.”

Gear Philosophy: Quality, Versatility, and British Heritage

Keira is unapologetic about the importance of quality gear. Her amplification of choice is Markbass, which she values for its combination of lightweight design and genuinely warm tone. “People have downsized their equipment — they don’t want to carry massive rigs anymore,” she explains. “Markbass was great because it was light as a feather, but you got a really warm sound out of the amps.”

For effects, Keira uses pedals from Flattley Guitar Pedals, drawn to both their analogue character and their aesthetic appeal. Importantly, she uses effects as textural tools rather than constant accompaniments — “I use them more in a texture sense rather than using them throughout the entire song.”

Why Rotosound? The Strings Behind the Groove

When it comes to strings, Keira doesn’t have to think twice: Rotosound. And her relationship with the brand predates any endorsement deal.

“Even before I got this endorsement, I knew that they were quality strings,” she says. “Those were the strings I used to put on my basses.”

For Keira, choosing Rotosound is personal as well as professional. As a UK-based artist, using a proudly British manufacturer matters to her. Founded in 1958 by James How in Woking, Surrey, Rotosound remains an independent, family-rooted company — and every Swing Bass 66 string is still hand-made on bespoke How-family machinery.

Her go-to is the Swing Bass 66 roundwound strings — specifically, the heavy gauge sets. With a musical life that involves significant amounts of drop tuning (Drop D, E♭, Drop C and beyond), heavier strings give her the tension and clarity she needs when tuning down.

“I’ve now learned to start using heavier strings because of that, because it can take those kinds of tunings a lot more. And even the lower you go, the clarity is still there.”

She’s also keen to point out that the Swing Bass 66‘s versatility suits her genre-hopping lifestyle perfectly — from rock and metal to funk and covers, these strings do the job across the board.

“I don’t just do rock metal — I do all sorts. Those strings are for any type of music. And I think that’s good — to have a company that isn’t niche. It doesn’t stick with just being a company for a particular style of music. It’s for everyone.”

Looking Ahead: Touring, Japan, and Wembley Dreams

Keira is not someone who sits still. Her ambitions are as large as her tone. She wants to tour internationally on a proper, sustained basis — something she hasn’t yet done despite her global gigging. The venues and festivals on her wish list include the legendary Whisky a Go Go in Los Angeles, Glastonbury, and Wacken Open Air. She’d also love to play the Montreal Jazz Festival — proof of how much that early exposure to jazz has stayed with her.

“I just love playing in general,” she says. “I’ve done covers, I’ve done originals, I’ve done online videos as well as teaching. I just like to expand my reach with what I can do in my musical career.”

With the drive, the technique, the influences, and the right strings on her precision bass, Keira Kenworthy is building something serious. We’re proud to have her in the Rotosound family — and we can’t wait to see where she goes next.