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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
4.43
65 Reviews
89%
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
- All types. of playing situations.1
- Studio1
- Not Consistent2
- Breaks Easy1
- Durability1
- Poor Quality1
- strings feel stiff1
- Experienced25
- Professional Musician9
- Novice3
- Good Tone33
- Consistent26
- Well Built / Quality25
- Long Life20
- Good tuning stability1
Reviewed by 65 customers
LOVE! these strings.
Verified Buyer
submitted3 months ago
byKevin
fromPittsburgh PA
Submitted as part of a sweepstakes
Started using these a few years ago, I used to only play XL's. I find that these strings bring my guitar to life. They also keep that crisp snappy sound through out the life of the strings.
Recording-Worthy Strings
Verified Buyer
submitted4 months ago
bySteve
fromCoral Springs, Florida, USA
Submitted as part of a sweepstakes
Ernie Ball is my favorite string for nearly all my guitars and basses. I've tried many strings on friends' instruments or as gifts, but they don't compare. I use regular Slinkys when gigging, Cobalts when recording. I note the difference. Cobalt are just a bit sweeter and clearer.
Quality strings
Verified Buyer
submitted9 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
submitted9 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
submitteda year ago
byVeronica
fromTexas
Submitted as part of a sweepstakes
One of my son's preferred brand of guitar strings.
Excellent Strings
Verified Buyer
submitted2 years 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.
Q&A
Have a question about this product? Our expert Gear Advisers have the answers.
submitted6 years ago
asked byTerry
fromKemp tx
Are these the nickle strings?
Yes they are.