Rotosound RS66LB Medium Light Bass Strings Review: The Sound of British Rock Royalty in a Box

Every bassist knows the feeling. You’ve got the perfect bass, the amp is dialed in, but the sound coming out is just… flat. It’s muddy, lacks definition, and gets lost the moment the guitars and drums kick in. For years, I found myself on this frustrating tonal treadmill, swapping pedals and tweaking EQ knobs in a desperate search for that elusive sound in my head: a tone with a snarling midrange, a crisp top-end that could slice through a dense mix, and a solid low-end foundation. It’s the sound of rock and roll bass – articulate, aggressive, and present. The problem, I eventually realised, wasn’t in the expensive electronics, but in the most fundamental connection between my fingers and the instrument: the strings. Using dull, lifeless strings is like trying to paint a masterpiece with murky watercolours. It suffocates your instrument’s true voice and neuters your performance. Finding the right set is not just an upgrade; it’s a revelation that unlocks the very soul of your bass.

What to Consider Before Buying Bass Guitar Strings

Bass strings are more than just four lengths of wire; they are a key solution for shaping your entire sonic identity. They dictate not only the tone—from warm and mellow to bright and aggressive—but also the feel, tension, and overall playability of your instrument. The right set can make your bass feel alive under your fingers, responding to every nuance of your playing. They provide the clarity needed for complex lines to be heard, the punch required to lock in with a drummer, and the sustain that lets notes ring out with authority. Without the right strings, even the most expensive custom-shop bass can sound cheap and uninspired.

The ideal customer for a set of bright, stainless steel roundwound strings is a player who needs to be heard. This includes rock, punk, funk, and metal bassists whose role is to provide not just a low-end foundation but also a driving, percussive, and melodic counterpoint. If you’re a slap player, you’ll crave the crisp attack these strings provide. However, they might not be suitable for those who prefer a more traditional, vintage sound. Bassists playing jazz, soul, or classic Motown often seek the warm, thumpy, and muted tone of flatwound strings, which have a completely different construction and sonic character. If you find roundwounds too abrasive on your fingers or frets, or the “zing” too overpowering, then alternatives like nickel-plated steel or pure nickel strings offer a warmer, smoother experience.

Before investing in a new set, consider these crucial points in detail:

• Scale Length & Winding: This is paramount for bass guitars. You must match the string’s scale length to your bass (e.g., short scale ~30″, medium ~32″, long ~34″, extra-long 35″+). Buying the wrong scale can result in strings being too short to reach the tuning post or having the thick part of the string wrap around the post, which can cause breakage. The Rotosound RS66LB Medium Light Bass Strings are designed for long scale basses up to 34 inches, the most common size.
• Gauge & Tension: String gauge refers to the diameter of the strings, measured in thousandths of an inch. The RS66LB set has gauges of .035, .055, .070, .090. This is a “medium light” set, offering a slinkier feel on the higher strings for easier bending and faster playing, while maintaining a solid feel on the lower strings for a robust fundamental. Heavier gauges provide more tension and a fatter tone, while lighter gauges are easier to play and sound brighter.
• Materials & Construction: This is the heart of a string’s tone. The Rotosound RS66LB are made from stainless steel wrapped around a hexagonal core. Stainless steel is known for its bright, crisp, and aggressive tone with a slightly rougher texture. This contrasts with nickel-plated steel, which is warmer and smoother to the touch, or flatwound strings, which use a flat ribbon winding for a deep, mellow, and smooth feel. Choosing the right material is key to achieving your desired sound.
• Ease of Use & Maintenance: These are uncoated strings, meaning there’s no protective layer between your fingers and the metal. This maximizes brightness and clarity but means they are more susceptible to dirt and oils from your hands. To prolong their life, it’s crucial to wipe them down with a clean cloth after every playing session. While they will eventually lose their initial zing, their usable life is often praised by long-term users.

Ultimately, your choice of strings is a deeply personal one that will define your interaction with your instrument. Now, let’s dive into one of the most iconic sets ever made.

While the Rotosound RS66LB Medium Light Bass Strings is an excellent choice, it’s always wise to see how it stacks up against the competition. For a broader look at all the top models, we highly recommend checking out our complete, in-depth guide:

First Impressions: Unpacking a Piece of Rock History

Opening a pack of Rotosound Swing Bass 66 strings feels less like unboxing a product and more like handling a piece of music history. The simple, iconic packaging has graced the gear bags of legends for over 50 years. Inside, each string is individually coiled in a paper envelope, and the first thing you notice are the vibrant red silk wraps at the ball end—a signature Rotosound touch. Pulling the strings out, the immediate tactile sensation is of quality and purpose. The stainless steel winding feels solid and has a distinct, grippy texture compared to smoother nickel strings. There’s a reassuring stiffness to them that promises tuning stability and a robust feel once installed. We strung them up on our trusty Fender Jazz Bass, a platform that, as one user rightly noted, is a perfect match for these strings. The installation was straightforward, with ample length for a standard 34” scale bass. The immediate visual of the gleaming steel against the fretboard and the flash of red silk at the bridge is classic and inspiring, making you eager to plug in and hear the sound they’re famous for. You can see the iconic design and packaging for yourself and understand why it’s a staple for so many players.

Performance Under Pressure: A Deep Dive into the Rotosound RS66LB

A string’s true worth is only revealed when it’s put through its paces—under bright stage lights, in a stuffy rehearsal room, and under the microscope of a studio recording. We spent weeks with the Rotosound RS66LB Medium Light Bass Strings on our primary test bass, subjecting them to everything from aggressive pick-driven punk rock to nuanced fingerstyle funk and percussive slap lines. This wasn’t just a test; it was an immersion into a sound that has defined generations of music.

The Sonic Signature: Chasing the Legendary “Swing Bass” Growl

Fresh out of the packet, the RS66LB strings are breathtakingly bright. The first notes you play are filled with a piano-like clarity, rich in harmonic overtones and a high-end “zing” that is unmistakably stainless steel. This isn’t a subtle warmth; it’s an assertive, in-your-face tone that demands attention. When playing with a pick, the sound is pure rock and roll authority. Each note has a sharp, percussive attack and a grinding metallic edge that’s perfect for driving eighth-note lines. This is the sound of John Entwistle of The Who, who co-developed these very strings with Rotosound back in 1966 to get the tone he needed.

Switching to fingerstyle, the character changes but the clarity remains. The strings are incredibly responsive to dynamics. Play softly, and you get a clean, articulate tone. Dig in, and you unleash the famous “Rotosound growl.” This is a complex, gritty midrange presence that helps the bass speak with its own voice instead of just occupying low-end frequencies. This is exactly what users refer to when they mention the “Geddy Lee” tone. Lee’s aggressive fingerstyle on his Jazz Bass with these strings created a benchmark for rock bass tone that is still sought after today. We found this growl was most prominent when playing over the bridge pickup, delivering a tight, focused sound that never got lost. You can explore getting this legendary growl for your own bass.

For slap and pop styles, these strings are an absolute dream. As one user confirmed, they are “perfect for slapping.” The high-end crispness makes every thumb slap percussive and every finger pop snap with authority. The stainless steel material provides a fast, articulate response that is essential for this technique. The sound is modern, hi-fi, and energetic, making them a fantastic choice for funk and fusion players who need their lines to be crystal clear.

Feel and Playability: A Tale of Balanced Tension

Tone is only half the story; the way strings feel under your fingers is just as critical. The “LB” in RS66LB stands for “Light Bottom,” but the gauge set (35-55-70-90) is more accurately described as a custom medium-light. The .035 G-string and .055 D-string feel nimble and fast, making intricate passages, chords, and slides feel effortless. They bend more easily than standard gauges, inviting a more expressive playing style. The tension is low enough to be comfortable for long gigs without causing excessive fatigue.

Conversely, the .070 A-string and .090 E-string provide a solid, stable foundation. They have enough mass and tension to deliver a powerful low-end fundamental without feeling loose or flabby, even when played aggressively or drop-tuned slightly. This balanced tension set is a brilliant compromise. It gives you the flexibility and speed of a lighter set on the higher strings while retaining the power and authority of a medium set on the lower strings. We found this combination to be incredibly versatile, adapting well to a wide range of playing techniques. This unique gauge set is a feature that really sets them apart for players seeking both flexibility and power.

It’s important to address the texture. Stainless steel is inherently rougher than nickel. As you slide your hand up and down the neck, you’ll hear more “zip” or finger noise. Some players love this, as it adds a bit of mechanical texture to the sound. Others may find it distracting or abrasive on their fingertips, especially during long slide-intensive passages. Similarly, this texture can accelerate fret wear over time compared to smoother strings. This is a trade-off: you get unparalleled brightness and growl in exchange for a more aggressive feel. For us, the tonal benefits far outweighed the textural quirks, but it’s a crucial factor for any potential buyer to consider.

Durability and Tonal Evolution: From Zing to Thump

No string stays bright forever, but the Rotosound RS66LB fights a valiant battle against time. As one user aptly put it, “They stay bright for a long time.” In our testing, that initial, almost overpowering “zing” lasted for about 8-10 hours of heavy playing. After this break-in period, the tone doesn’t die; it matures. The super-high frequencies roll off slightly, and the aggressive midrange growl becomes even more pronounced. This is the sweet spot for many rock players, where the string has settled in but retains all of its punch and definition. This “settled” tone can last for many weeks of regular playing, a testament to the quality of the UK-made stainless steel.

We found their longevity to be a major selling point. Cheaper strings often go from bright to completely dead in a very short period, with no pleasant middle ground. The RS66LB, however, has a graceful and useful tonal decay. Once they do lose their characteristic punch, they settle into a more generic, warm rock tone that is still perfectly usable for rehearsals or practice. Wiping the strings down after each use significantly extends that coveted bright phase. The fact that users report keeping the same set on their basses for long periods and still being happy with the sound speaks volumes about their durability. The combination of iconic tone and impressive lifespan represents outstanding value for any serious bassist.

What Other Users Are Saying

Our positive experience with the Rotosound RS66LB Medium Light Bass Strings is strongly mirrored in the feedback from the wider playing community. There is a clear consensus among users that these strings are the go-to choice for achieving a specific, legendary rock tone. One player explicitly states they use them on all their Jazz basses to “get that ‘Geddy Lee’ growl,” adding that they “wouldn’t use any other bass strings.” This sentiment is a powerful endorsement of the strings’ unique sonic character.

The theme of longevity is also prevalent, with the same user noting that “they stay bright for a long time.” Another bassist confirmed this, mentioning that this was their second set and “both sets are still on the basses,” highlighting their durability. The appeal transcends genre and instrument, with one musician having great success installing them on an acoustic guitar they converted into a hollow body bass. Another user simply states they are “Perfect for my Stingray,” a bass known for its punchy, aggressive sound, confirming the strings are a perfect match. This widespread praise, from players of vintage instruments to modern ones, underscores the timeless and reliable quality that Rotosound delivers. You can see more detailed user experiences and reviews online.

How Does the Rotosound RS66LB Compare to the Alternatives?

While the RS66LB holds a legendary status, the bass string market is filled with excellent options catering to different tastes. Understanding how they stack up against key competitors is crucial for making an informed decision.

1. Rotosound RS77LD Flatwound Bass Strings

This is the yin to the RS66LB’s yang, even within the same brand. The RS77LD are Monel flatwound strings, delivering a sound that is the polar opposite of the bright stainless steel roundwounds. Their tone is deep, warm, and fundamental-heavy, with a very quick decay—the classic “thump” of 1960s Motown and soul music. The flat ribbon winding makes them incredibly smooth to the touch, eliminating finger noise and being very gentle on frets. A player might choose the RS77LD over the RS66LB if they are seeking a vintage, mellow tone for jazz, soul, or R&B, or if they simply cannot tolerate the texture and brightness of roundwounds.

2. Ernie Ball Regular Slinky Bass Strings

Ernie Ball Slinkys are arguably the other heavyweight champion in the world of roundwound bass strings. The primary difference lies in the material: Slinkys use a nickel-plated steel wrap wire. This results in a tone that is still bright and punchy, but noticeably warmer and with less aggressive high-end “zing” compared to the Rotosound’s stainless steel. They also feel much smoother under the fingers. A bassist would choose Ernie Ball Slinkys if they want a versatile, all-purpose roundwound sound that is slightly less abrasive and aggressive than the RS66LB, making it a great middle-ground for a wide variety of genres.

3. DR Strings FAT-BEAM Stainless Steel Bass Strings 5-String Medium

The DR Strings FAT-BEAM set is a direct competitor in the stainless steel category, but with two key differences: it’s a 5-string set and it features DR’s unique construction. FAT-BEAMs are also known for their brightness and punch, often described as having a slightly deeper low-mid presence compared to the Rotosounds. DR strings are hand-wound on a round core, which some players feel gives them a more flexible feel and enhanced sustain. A 5-string bassist looking for a premium stainless steel sound, or a 4-string player who prefers the feel and tonal character of round-core strings, might gravitate towards the DR FAT-BEAMs as a high-quality alternative.

Our Final Verdict on the Rotosound RS66LB Medium Light Bass Strings

After extensive testing, it is clear that the Rotosound RS66LB Medium Light Bass Strings are not just a product; they are a benchmark. They offer a direct line to the sound that has driven countless iconic rock albums for over half a century. Their unparalleled brightness, aggressive midrange growl, and percussive attack make them an essential tool for any bassist who needs to cut through a loud band and make a powerful statement. While the rough stainless steel texture isn’t for everyone and requires a trade-off in fret wear, the sonic rewards are undeniable.

We wholeheartedly recommend these strings to any rock, funk, or punk bassist looking to inject their sound with energy, clarity, and attitude. They are the definitive choice for achieving that legendary, growling tone made famous by icons like Entwistle, Squire, and Lee. For the sound they deliver and the durability they offer, they represent fantastic value and a true upgrade for any suitable bass. If you’re ready to stop blending in and start standing out, these strings are your ticket. You can check the latest price and add this legendary tone to your setup today.