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Ernie Ball 2721 Cobalt Regular Slinky Electric Guitar Strings

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The Ernie Ball Slinky Story

Ernie Ball String Explorer: Electric Slinky Nickel Wound SSS

Ernie Ball String Explorer: Electric Slinky Nickel Wound HH

Ernie Ball: The Colors of Rock 'N' Roll

Description
This innovative set of strings is engineered with a cobalt alloy core that provides guitarists an unparalleled experience. The cobalt blend is highly magnetic, enabling your pickups to translate the strings' vibrations with unrivaled clarity and definition across the tonal spectrum. The result is beefed-up low end, crystalline highs, and a robust midrange that cuts through any mix.
Unmatched Sonic Performance
Cobalt's superior magnetic qualities empower your instrument to reach its full potential. These strings drive your pickups to new levels of sensitivity for tones that are powerful yet nuanced. Expect an output boost along with enhanced harmonic richness and sustain. The cobalt core also provides a silky feel that facilitates fluid playability. Once you string up with Cobalts, you'll never go back.
Long-Lasting and Corrosion-Resistant
Cobalt strings are built to rigorous quality standards using premium materials for maximum longevity and performance. Their cobalt core is highly resistant to corrosion and oxidation, even with heavy use. These strings retain tone and intonation over a long lifespan, reducing frequent restrings. They also hold up well to environmental and chemical exposure from sweat and other contaminants. For guitarists seeking a high-performance, low-maintenance string, Cobalts are the ideal choice.
The Choice of Discerning Professionals
Cobalt strings are favored by top musicians for their unmatched performance and tone. Icons like Slash, John Petrucci, and Steve Vai rely on Cobalts to achieve their signature sounds. These strings put the same elite tone and feel into any guitarist's hands. Experience the Cobalt difference—your tone and technique will never be the same.


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Reviews
4.41
63 Reviews
88%
of respondents would recommend this to a friend
Most Liked Positive Review
I like them, but...
I'll cut to the chase. As compared to the run-of-the-mill nickel strings... THE GOOD 1) Smooth feel 2) Slightly increased output 3) Better definition/clarity (bright, but not tinny/shrill) 4) Very good tuning stability - tuned up to pitch quickly and stayed there very consistently THE NOT-SO-GOOD 1) A bit pricey 2) Very small drop in "warmth" - didn't bother me much So I really liked these as compared to nickel strings. However, I use GHS Progressives. Compared to these, the Cobalts have fewer advantages. Tonally, I think they are on the same level. The Cobalts may have a bit more output and smoother feel. The tuning stability might sway me to these. I'll need to see how they hold up over time. Only 1 gig on the Cobalts so far, so I'll need to weigh-in on the longevity at a later date. That will also give me some time to refine my opinion as the strings "season". Definitely worth a try as they do provide non-trivial differences. Everyone has different tastes, so no better way to decide than for yourself!
Most Liked Negative Review
Overpriced and Underperforming
Bought a 3-Pack of 10's. Right out of the package the 0.46 felt "Ruff" and Rusty, not smooth at all. All 3 packs had a similar "Ruff" almost "Tacky" feel on the 0.46, 0.36 and 0.26. The solid wire strings were quite smooth. Strung up my PRS Custom 24 to start, tried the Strat next. Clearly a much brighter tone than your typical Nickel wound string. Within a week the 0.46 on the PRS Custom 24 showed signs of what looked to be rust. This guitar was exposed to daily play and practice. Brightness seemed to decay on both instruments after a Month. Tone 5/5, Consistency 3/5, Quality 1/5. Verdict: Save your money, and go buy better Guitars, Pickups and Tube Amps instead.
- Practicing17
- Concerts14
- Back-Up5
- Studio1
- All1
- Not Consistent2
- Breaks Easy1
- Durability1
- Poor Quality1
- strings feel stiff1
- Experienced24
- Professional Musician8
- Novice3
- Good Tone31
- Consistent24
- Well Built / Quality23
- Long Life18
- Good tuning stability1
Reviewed by 63 customers
Quality strings
Verified Buyer
submitted5 months ago
byGavin
fromLos Angeles, CA
Submitted as part of a sweepstakes
Use these on all my guitars now (single coils and humbuckers), really bring out the brightness and, of course, volume. Highly recommended for all scenarios, practice, studio, and stage. Wear well, reasonably priced, and feel just right in terms of smooth v course. Look out for offers from Guitar Center, and buy in bulk!
Quality strings
Verified Buyer
submitted6 months ago
byGavin
fromLos Angeles CA
Submitted as part of a sweepstakes
Nice bright but balanced tone, strong and easy to bend. No sign of wear after a month. Putting these on all my guitars from now on. #sweepstakes
Good brand
Verified Buyer
submitted10 months ago
byVeronica
fromTexas
Submitted as part of a sweepstakes
One of my son's preferred brand of guitar strings.
Excellent Strings
Verified Buyer
submitteda year ago
byBrian
fromLos Lunas ,New mexico
Submitted as part of a sweepstakes
Very high quality strings with great sustain, tone and strength.Really put these to the test with some brutal riffing and stayed in tune throughout the session.Plan on buying more.
I would buy these strings again.
Verified Buyer
submitteda year ago
byMitch
fromNew York
Submitted as part of a sweepstakes
I put them on my Les Paul Trad Pro. They are very crisp and clear. Each note rings out with clarity. I don't use pedals much because I prefer the pure sound of the guitar and these strings sound great.
Good strings after a few plays
submitted2 years ago
byJordan
fromMaine
These strings have good tone and tuning stability after the initial break in. They can be a bit shrill when they're fresh, so just a word if caution for those with brighter, higher output pickups. #sweepstakes
Q&A
Have a question about this product? Our expert Gear Advisers have the answers.
submitted5 years ago
asked byTerry
fromKemp tx
Are these the nickle strings?
Yes they are.