Ernie Ball Extra Slinky Bass (.040–.095) review: the exact gauge on Roger Glover's signature Vigier

Ernie Ball's Extra Slinky Bass is the lightest of seven gauges in the company's 4-string nickel Slinky bass family, running .040, .060, .070, .095, wound on a hex steel core, built for standard long-scale bass. Ernie Ball's own product page describes the whole nickel bass line in one line: strings "made from nickel plated steel wrapped around a hex shaped steel core wire," producing "a bright, balanced tone." Source: Ernie Ball's own Extra Slinky Bass product page.

It's also a factory match for a real, working bass. Vigier's own spec sheet for the Excess Roger Glover Original, the signature bass Deep Purple's Roger Glover has played since the mid-1990s, lists the factory string gauge as .040-.095, identical to this set. Wikipedia's sourced profile documents Glover himself using Ernie Ball and Picato strings since that same era, though it names no specific model or gauge, so CYS can't say he strings his own Vigier with this exact Ernie Ball set. What's verifiable is narrower and still useful: if you own or are restringing a Roger Glover Original to factory spec, this is the gauge.

Extra Slinky sits at the bottom of Ernie Ball's broader nickel 4-string bass family (light to heavy): Extra Slinky (.040-.095), Hyper Slinky (.040-.100), Super Slinky (.045-.100), Hybrid Slinky (.045-.105), Regular Slinky (.050-.105), Power Slinky (.055-.110), and Beefy Slinky (.065-.130), confirmed on Ernie Ball's own catalog page. It shares its top string exactly with Hyper Slinky, then steps down to a noticeably lighter A and E, the easiest-fretting gauge in the whole nickel line.

Roger Glover co-founded Deep Purple's classic Mark II lineup in 1969 and has anchored the band's bass chair across two stretches spanning more than four decades. Since the mid-1990s he's played a Vigier signature bass, the Excess Roger Glover Original, a solid alder body, maple neck, 24-fret, 33.8-inch-scale instrument built in France. Vigier's own spec sheet lists the factory string gauge plainly: "Strings: .040-.095." Source: Vigier Guitars, official product page.

That's this exact Ernie Ball set. To be precise about what is and isn't documented: Wikipedia's sourced profile, citing a Guitar magazine interview from October 2003, confirms Glover has used Ernie Ball and the UK maker Picato as his strings since the mid-1990s, the same period he moved to Vigier. It does not confirm which specific set or gauge he personally strings his bass with today. So this isn't a documented Roger Glover endorsement, it's a documented instrument spec. If you play, or are restringing, a Roger Glover Original to the factory setup, Extra Slinky Bass is the set that matches it.

Ernie Ball ships seven gauges under its nickel Slinky 4-string bass line, all confirmed live on Ernie Ball's own catalog page, each with its own individual 4-string gauge breakdown:

• Extra Slinky: .040, .060, .070, .095 (P02835), this set, the lightest.
• Hyper Slinky: .040, .060, .080, .100 (P02841). Full review.
• Super Slinky: .045, .065, .080, .100 (P02834). Full review.
• Hybrid Slinky: .045, .065, .085, .105 (P02833). Full review.
• Regular Slinky: .050, .070, .085, .105 (P02832), Ernie Ball's standard-tuning default. Full review.
• Power Slinky: .055, .075, .090, .110 (P02831).
• Beefy Slinky: .065, .080, .100, .130 (P02840), the heaviest.

Extra Slinky and Hyper Slinky share an identical .040 G and .060 D string, so the two only diverge on the A and E: .070 and .095 here, versus .080 and .100 on Hyper Slinky. A player who finds Super Slinky Bass too tense across the board, and wants the lightest possible feel without leaving the nickel Slinky family, lands on Extra Slinky.

Ernie Ball isn't the only brand selling a "40-95" 4-string bass set. DR Strings' Pure Blues Victor Wooten Signature, Victor Wooten's own signature model, carries the same nominal .040-.095 range, but the two sets are not the same strings. The outer G and E match exactly; the inner D and A don't.

The practical takeaway: don't assume two "40-95" sets from different brands feel the same on the D and A strings. The two brands don't just split lighter-versus-heavier, they trade thickness: Ernie Ball runs a thicker D string (.060 versus DR's .055) but a thinner A string (.070 versus DR's .075), so the tension balance across the middle of the set isn't identical even though both start and end on the same .040 and .095 outer strings. Ernie Ball's hex core is also a stiffer construction than DR's round core, which DR's own materials describe as more flexible and responsive under the fingers. Neither is more "correct," they're built for different feel targets, but the shared "40-95" label hides a real difference. For the full breakdown of Victor Wooten's own gear and his DR signature set, see DR Pure Blues Victor Wooten Signature's full review.

• Restringing a Vigier Roger Glover Original, or any 4-string bass factory-strung at .040-.095, to its stock spec.
• Players who want the lightest playable tension in Ernie Ball's nickel Slinky bass line, without moving to a coated or Cobalt alternative.
• Fast technique: slap, tapping, and quick position changes benefit from the reduced string tension versus Super Slinky or Regular Slinky Bass.
• Players who want the classic bright nickel tone over a coated or Cobalt alternative.

• Drop tunings played stock. A .095 low E is already light for standard tuning; drop it further and it goes slack fast. Look at Regular Slinky, Power Slinky, or a 5-string set instead.
• Players chasing maximum string life. This is an uncoated roundwound set with the standard wear curve.
• Players who want more low-end mass and output. Hyper Slinky, Super Slinky, and the heavier sets in the same nickel family add string mass without changing the brand or winding style.

Standard nickel roundwound install: stretch each string after tuning to pitch, pull up gently a few times along its length, retune, and repeat two or three times before trusting it on stage or in a session. Expect 15 to 20 minutes of playing before the top end settles into its final voice. Because this is the lightest gauge in Ernie Ball's nickel bass family, double-check your nut slots aren't cut for a heavier set (Super Slinky Bass or up) before installing; a too-wide slot lets a light string rattle or sit off-center, and check your bridge saddle intonation screws have enough travel for the reduced string diameter.

Extra Slinky Bass is Ernie Ball's lightest 4-string gauge, and the one number that matters most about it isn't a player endorsement, it's a factory spec: this is the exact gauge Vigier ships on Roger Glover's signature bass. If you own that instrument, or any bass built around a .040-.095 factory spread, and want to stay at stock tension with a straightforward, well-distributed nickel brand, this is the match.

If you're not restringing to a specific factory spec and just want the easiest possible fretting hand on a standard long-scale bass, it's still a reasonable starting point, just know the .095 low E is light enough that drop tunings and aggressive attack will ask more of it than it's built to give.