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Ernie Ball 2721 Regular Slinky Cobalt Electric Guitar Strings - .010-.046 Reviews

.010-.046 Electric Guitar Strings - Cobalt

Ernie Ball Cobalt guitar strings are made of a new alloy formulation that gives you higher output, better sound, and longer life. Cobalt strings' special iron/cobalt blend attracts the magnets in your pickups better than any other alloy. When you string up with Ernie Ball Cobalts, you'll immediately notice the incredible comfort these strings offer - silky and pliable under your fretting fingers; your pick will seem to glide over the strings, letting you execute fast passages effortlessly. And when you plug in, you'll get increased power, beefy yet defined lows, improved midrange focus, harmonics, and sustain, and crisp highs. Try a set of Ernie Ball Cobalt strings - you're gonna love 'em!

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Highest Rated Reviews

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Amazing

By Michael Petett from CANYON COUNTRY, CA on January 30, 2024

These strings made a shocking improvement to my sound.

Want low-tension strings for your acoustic? Instead of $26/set strings, try these.

By Jim Casler from NEWTON, NJ on January 19, 2023

You read that right, I put 'em on my acoustics, and they sound great. Even, not woofy or boomy, and they feel like nothing else you might have tried. I had a set of these on my old Alvarez 5059. Took those off and tried D'Addario Balanced Tension 10-46. Had those on for one day. One day, and I was saying, "I want my Balls back!" Put on a fresh set of these, and I'm a happy camper. Great if you're accompanying a singer, as they don't produce a lot of voice-burying noisy harmonics.

Best strings I've ever used

By Ed from Jackson on January 23, 2022 Music Background: Guitarist for I Decide I

Exceptional tone and playability, they feel great, I run them on my 7 strings and they're the best strings I've used to date.
I noticed that a bunch of the poor reviews talking about string breakages I have yet to have that issue. I also notice them talking about regular slinkys being better when in fact they're the same exact string with a different wrapping, which is why they a tad more and sound better. Returning to what I was saying these strings outclass so many brands and they do not disappoint.

The remedy for a nickel allergy

By Sam Small from Los Angeles, CA on January 4, 2020 Music Background: Professional touring and session guitarist

I'm a touring and session guitarist and have been playing for a long time now. I, as well as a small number of my colleagues, have a nickel allergy. This poses a huge problem as most electric guitar strings are wound with nickel. For the longest time, I had to use stainless steel strings, which are harsh sounding and feeling. However, when I discover the Ernie Ball Cobalts, I was blown away. They have no nickel but feel like regular guitar strings. The sound is full and natural sounding. If you, like me, have a nickel allergy (or you don't and just like great guitar strings) try the cobalts.

Made Me A Believer

By William Maxwell from Cullman, AL on January 3, 2020 Music Background: Home Recording

I have a Gibson LP and even though I like brite-wires I just wasn't sure about the sound when it came time to record. So I went on a mission to try and find the perfect strings to help achieve the sound I was looking for when the guy at my local shop suggested these. For real I've always hated Ernie Ball strings until I tried these things. What a difference. They give you more output and string definition. I did some setup adjustments to help harmonize the strings to my liking and that thing sounds great. If you haven't tried these already I would definitely recommend it. They might just give you the sound your looking for.

Best strings period!

By Rafael from New Mexico on October 3, 2018 Music Background: Musician full time

I have used regular Slinky's for years and decided to give the Cobalts a try. I immediately heard a huge difference in tone, feel, etc. Amazing.
I went back to the Slinky's again and just didn't get the same as the Cobalt's. Very noticeably different.
So, gonna stick to the Cobalt's from now on.
Best strings period! ✌

Superb Strings period

By Sweetwater Customer from MISSISSIPPI on April 22, 2017 Music Background: 20+ year pro

I was reluctant but a friend gave me a set. Ive used the D'addarios for years. Just happened to break a string and his gift set was all I had. Tied`em on and wow. They were full of tone, and slightly louder I suppose. But Tone for days. So, I started using them and have been ever since. I have tried some of the coated strings and they`re just too bright and jangle. These strings are awesome. But I would reluctantly state that these strings are maybe not for beginners nor those who don`t play their guitar regularly, because they are strong. But if you are a daily player you`ll not notice the difference. They also last longer. My normal time frame, when gigging steadily, on a set of strings before using these was about once every week or two, now, I tie on a new set about once every 3-4 weeks.

Best string out there

By Shawn from Poconos pa on March 25, 2017

I bought these strings to try out on my Les Paul will never buy anything else they sound so nice clear you can hear ever note I'll I have to say is people that don't like them are to cheap to pay the price of the strings or they are playing on guitars that are not set up properly if your guitar is not set up right you will never hear the beauty these strings give these string are for pro's if your a beginner you will think a ten dollar fleamarket amp sounds great Lmao

Put Some Grrr in your Guitar

By Eric from San Francisco on January 3, 2017 Music Background: Years of classical way back when, now just a hobbyist

I've been playing Regular Slinkies for a while now on all my electrics, but I just restrung two of them with Cobalt Slinkies. I was literally taken aback. It's like I'd turned up my amp or something. I never thought I'd get this kind of sustain out of a Telecaster…and the Les Paul…. Wow. I'm pretty sure I heard upper partials I didn't know existed coming out of an electric guitar.

You might actually irritate your drummer, the way these things cut through the mix.

wow!

By Sweetwater Customer from fairfield california on February 19, 2016

iv been playing GHS strings for years ,and a friend told me to try these out.i cant believe how good they are! I play metal mostly with high gain amps and these strings really clean up your sound.arpeggios sound totally different you can hear every note better and they seem to be louder as well its pretty crazy iv never been so happy with a pair of strings before.

Very Noticeable Difference

By EdKo from Niagara Falls NY on January 28, 2016 Music Background: Professional

It's amazing the difference these strings actually make. The feel is just awesome. I've been a die hard Daddario guy for 30 plus years and these have made me switch. They need to be tried out to be believed. seriously, its a actual improvement in guitar strings.

Ernie Ball cobalt 10-46

By steven from wi on August 11, 2015 Music Background: home recording, hobby

These are awesome strings. Last longer, sound much better, and they have a very smooth silky feel to them. They are pricey but they are worth it. Used D'addario for 25+years and will never go back. Thanks to Andy Plank at Sweetwater for ridiculous fast service!!

Changed all my strings after one use to this specific one

By Amos from Washington state on April 24, 2015 Music Background: 10 years

Was a fan of the orange diadario till a buddy gave me a set of these. After a few minutes I ordered them for all my guitars. You can play for hours and have no finger wear at all. So smooth to the touch and a great sound too! Stronger than others as well and they stay in time exceptionally well

one killer set of strings

By Brendan Steed from Ft. Wayne, IN on January 27, 2015 Music Background: Sweetwater Employee, Audio Engineer, Guitar Builder, Guitar Player.

If you are looking for a straight metal sound or just want more gain without having to twist the knob on your amp or are just looking for a very versatile and playable set of strings that will give you great volume and tone on whatever tone you play on well then these are for you. I strapped these onto my 72 reissued Telecaster thinline and wow what an improvement in overall tone and sound. I now have more gain then I know what to do with and my tone control on my guitar has never been so noticeable. These are an amazing set of strings and I will start putting them on all of my electric guitars.

VERY COOL!!!

By Bryon Weaver from United States on February 11, 2014 Music Background: 40+ years playin' Blues, Rock, Country, and Jazz.

First of all I've been a regular slinky fan for 40 years! I've tried a few different brands over the years. And the only ones that came close to my ears were the GHS Boomers. But they didn't cut the mustard... That was 20 years ago. And only because our lead player used them. He was wrong!!! Reg Slinky's are the best I've ever used! Until now... These "Cobalts" are better! They hold their intonation even when new!!! And they really do make your axe sound better!!! Point in case... I bought a Gibson "SGJ14" in December and thought it was weak. And stated so in my review. You can read it for yourself! And at the time I meant every word of it!!! I thought the pups sucked! But after a couple weeks, I broke one of the strings Gibson put on it from the factory. So I decided to put the "Cobalts" I bought during the holiday season. What a difference!!! I couldn't believe the tone I was getting just by changing my strings!!! It was truly amazing. I can't wait to replace the strings on my other guitars! Give them a try Mikey, you'll like 'em!

Good bye Elixir

By mark from augusta ga on July 5, 2012 Music Background: semi

I have played since 1974. I remember back in the 70's when strings broke for me on a regular basis. I read about these in a interview with The ball family in Guitar player and felt "why not?" .. I put them on my 2012 Les paul classic custom since I had some issues with elixirs ( was my favorites) staying in tune on it. it was also a instructional moment for my daughter showing her the right way to string em up.
Once i was done and tuned up I proceeded to play the hell out of them doing all sorts of bends and such for about 30 mins. My daughter asked me what was wrong. I was blown away. Still in tune. I have never had strings hold tune like that being brand new. I swear never have I been so sold on something. That was 2 weeks ago and have only had to make a few adjustments. Outstanding !!!!!!

Ernie Ball Slinky Cobalt (Hawaii)

By RJ Kaneao from Waikoloa, HI USA on June 17, 2012 Music Background: Artist,musician,producer,recording engineer and Ernie Ball- Music ManArtist

I've tried many different strings and wasn't to much a gimmick biter.. Everyone claims to have the best strings and rightfully they should feel that way cause it's their own product.. I have two small string endorsements that I've had for awhile until I got signed by Ernie Ball-music man a month or so ago.. I've used their super slinky for years and lets face it "there's nothing better then a great set of fresh strings on your instruments"! Being that this is my comment and review on these Cobalts I want you to know in no way am I bring partial or bias but giving you a true fact! Ready? Here it comes.. "Ernie Ball Cobalt strings are the best strings I've ever used in my entire life"! I've been a solidified professional full-time musician for 17 years and counting and I'm on stage a minimum of twice a week to 6-7 days a week.. I've literally tried them all or atleast I feel I have.. These strings are a pleasure to use and feel so seductive and light but still holds beautiful tone,sustain is amazing and the output seems to have more gain in it.. Idk what else I could say but this " best strings on the market" hands down! Aloha

I was a GHS Boomer guy... until now...

By MA Mealer from Tunnel Hill, Ga on June 1, 2012 Music Background: Church Musician

Best tone out of a string I've had in a long time. They stretch out well and my guitar just seemed to have higher, clearer output. I didn't believe there could be that much of a difference between string brands, but this one blows away all the others by far!

thought it was just hype

By Gary Gambill from Wausau,Wi on March 4, 2012 Music Background: Music teacher

I don't buy into the next big thing most of the time,but i thought i would try these strings.I noticed a big difference right away.I bought the 10-46 set but to me they play and feel like a 9 set.for some reason the tension seems lighter more rubbery in a sense.I had my setup the same as far as guitar amps and so on,and there is a volume difference.A person just learning to play might not notice it,but its like there is more of what was there before,if that makes sense.I haven't put down my guitar for about 4 hours now,everything seems to be easier to play.....a bit more smooth....

Crazy Strings

By Andrew M from Louisiana on April 9, 2023

I'm going to be honest, I'm not 100% sure I actually like them enough to keep buying them. When I bought them I saw the description saying things like 'higher pickup output' 'thicker tone' etc, etc, and assumed it was all marketing boast. I was just feeling frisky and giving them a go to try something different. Imagine my surprise when it was all TRUE. These things are absolutely bonkers! The mids and mid-lows are SO strong and pronounced. The output really is stronger through the pickups - like - a LOT stronger. I'm getting breakup on my amp at about 10% gain whereas I wouldn't start getting breakup until at least 40% or higher, and it's all mids. There's such an immediate and noticeable difference in sound from all of this that you can't help but love it. When I threw them on, I spent a solid 30-40 mins doing nothing but riffing and had a big **** smile on my face the entire time. It sounded so gnarly - just the meanest snarls and growls coming from my guitar that I had ever heard. I immediately ordered another set to string up my other electric with.

The next day, however, I was less impressed. Once the immediate fun of having my guitar sound like it was possessed by a snarling hell beast wore off, I noticed that there was a complete and total lack of 'shimmer' or delicateness of any kind. No amount of eq'ing on my amp could get a less boomy and growly sound. Actually, that's not true, I could barely eek something out, but these definitely are not as versatile as any other string I've ever used. I recorded a little with them and the final sound wasn't as bad as I feared, maybe even kind of good. My second order of strings hadn't shipped yet, so I went as far as to cancel that order. I likely won't string my other guitar with them. I'm debating whether they're worth keeping. I guess I just need more time to play with them and see how things go. I'm really intrigued by someone else's review suggesting to try to them on acoustic - I might have to give that a try. Either way, I am leaving a 4.5 star review, because the strings really do deliver on everything they promise and I did have the biggest **** smile on my face when I was riffing away with them at first. If you want your axe to growl like a rabid dog and snarl like some kind of hellbeast, then you should definitely get these. There are worse ways to blow $10 or $11.

Deep Tone and Punch

By Sweetwater Customer on July 9, 2020 Music Background: 2+ year guitarist. Drummer forever!

Had played Elixir 10's for a long time on my CE 24. Decided to try these based on reviews. The depth in tone of these stings is amazing. I tune to D Standard and they can bring the heavy. A little tacky at first and a bit of finger noise (compared to the polywebs I was using) but all in all great strings. Going to try the 9's out too on my RG. Well worth the $$$$ for the tone and lifespan.

High quality strings

By Jacob on September 21, 2019 Music Background: 60's, thru 90's rock

I have an Ibanez Art-100 that I changed the pickups to a Dimarzio X2N in the bridge, and a Dimarzio DP-156 in the neck. I put in the 10-46 Cobalt strings. These strings have a great tone, break in time was minutes, and they stay in tune. They have a PERFECT tone on the neck pickup clean amp, & great tone and growl with the bridge pickup dirty amp. I have tried many different brands looking for the tone I wanted until trying these. I will look no further, these are it, IMO with my setup. Amp used is a Blackstar. I don't think any strings will suit all players and guitars, but these are worth trying. I will be putting a set on my ES-335 next!

Perfectly fine

By Tim on October 11, 2016 Music Background: 40+ years, almost semi professional

The Cobalt 10s have been my string of choice for the last few years. I can't go overboard; it's not like they turn me into Brent Mason or Jimi Hendrix. But they've got a nice ringing tone and last longer than regular strings, so they are worth the premium, especially at the bulk discount. I mainly use them for blues, rock, and country. And, as everyone else says, Sweetwater's customer service is the best.

These are nice

By Corey from Washington on October 10, 2015 Music Background: Gigging/recording guitarist, guitar tech, repair, maintenance and restoration

Ive been using these since they came out. Ive used the 9's and 10's. They are a bit louder, clearer and have more highs than regular Slinkys. From my testing thus far, they seem to retain their tone for longer than standard Slinkys. They do feel different to play, and you may not like that at first but once you get used to it, its no big deal. Many people seem to have a problem with these breaking while they are still very new. I have never had that happen. I make sure my string pressure points at the nut and bridge saddles on fixed or vibrato bridges are smoothed so they have no sharp edges. In fact, Ive never broken and Ernie Ball Guitar string. The only drawback to Cobalts is that they are very bright. On some guitars they are too bright. One of my guitars just didn't work with Cobalts. They were too bright. Generally though, they are very nice, sound clear and full and sound fresh longer than standard strings. I think they are a bit expensive though so I only use them on some of my guitars. Ill keep trying strings of all brands and materials, but Ernie Ball Cobalts are at the top of my list right now. Give them a try. They might not be for everybody but I think they're great.

I used them for a couple years

By M'Ike from Washington on April 17, 2015 Music Background: Live and Recording Musician

I put these on a Schecter 006 Elite with stock Duncan Designed pickups. I have used DR MT-10s for about 20-25 years but on my Schecter they sounded a little smeared on the G, B, and high E strings. After reading about the Cobalts in a guitar magazine I decided to pick up a set.

The positives of these strings are that they are slightly louder and a little brighter than nickel wound strings, such as the DR MT-10s, and have noticeably more definition on the G, B, and high E strings. They stay in tune well and tune right up.

The downsides are that they have a stiffer feel, are a little more difficult to bend, and due to the hardness of the metal will chew up your picks (plectrums?). Also, instead of losing their liveliness gradually, they kind of hit a wall and lose life very quickly.

My verdict is that for a guitar with pickups that aren't that great, or on a dark sounding guitar, these will improve your sound, especially if you want some more definition than the standard nickel wound strings provide. If you prefer easy bending and a more predictable loss of string life, I'd suggest not using the cobalts.

Strings not living up to its hype

By David Niles from Texas on March 23, 2020 Music Background: Rock, metal,

I bought these strings in hoping that they would be in the same style, feel, and tone of regular EB's. After putting these on my ESP 256 guitar I did notice that my sound and tone was more clearer, and did bring some extra umff to my overall sound. The down side unfortunatly is that the strings feel very stiff and sterile, compared to the regular EB Slinky's. While these arent bad strings, I will stick to the regular EB's, that feel way better and are tested, tried and true strings.

Mixed bag

By Greg from Asbury Park, NJ on April 9, 2017 Music Background: Guitarist and engineer

I'm a fan of Ernie Ball strings and I think that a lot of the new offerings are excellent. However, I do have a little problem with these Cobalt strings. They sound great and are loud and defined and bend fairly easily. My issue is not with tone or output; it's with the feel under my fingers. I hate the way they feel. They Remind me of the feel of flatwounds. They seem to grab and hold my fingers, making it hard to slide and move up and down the fingerboard, and feel rough and abrasive. I like a smooth string. I want to love these strings because they do sound good, but they just don't feel good to me, and in the end if a string doesn't feel good you're not gonna want to play with it. The new Titanium, on the other hand; those feel great!

Not worth the extra money

By Donald on August 16, 2015 Music Background: Gigging Musician

I've been using Ernie Ball strings for 20+ years. I found these strings stiff compared to the regular slinky strings. I broke a string after 3 hours of live play. I haven't broke a string at a gig in years. In my opinion, while they do sound very good, I can't justify the cost difference.

Hard

By Art from CT on August 26, 2013 Music Background: Hobbyist

Lots of sound from these.
But they're hard. Very hard. Compared to regular 10's, I had to adjust the truss rod cause they pull the neck so hard. And unless you have decent calluses, they are hard on the fingers too.

But they do sound very good - making the twang in a Telecaster even more crisp.

Not worth it

By Jason Goodwin from Wisconsin on March 31, 2015 Music Background: 28 year vet

I have been playing guitar for 28 years and have always been an Ernie Ball user on all my electric guitars. I usually don't stray from regular Ernie Ball slinky 10s but tried these on a whim. These do nothing to increase volume or output and actually lack that bell-like clarity that regular slinky strings have. To my ears they sounded like dead strings that stay in tune. Overpriced. Hype. I won't buy these again.

Disappointed

By Shawn from Argenta, IL USA on July 16, 2012 Music Background: Audio Engineer, Producer, Singer/Songwriter, Artist, Pro

I've been a Slinky user for a long time and although these strings sound good, they didn't hold up for my playing. After one gig, they were breaking ( I haven't broke a string in years ). I have acidity hands so I have to wipe the strings clean after every set but it didn't help a bit. I believe I'll go back to the long life coated slinkys as they are more dependable for my playing.

broken string 1st song

By jay from fl on August 10, 2018

I play a lot, I have 3-4 hour gigs and rarely break strings. If i do, its beacuse I'm using a guitar that I've already played a few shows with. I put a brand new set of these on and snapped my high E before our first song was over. Brand new strings!!!.....that's never happened. On my trusted Les Paul too.

I won't use these anymore.

Not Impressed

By Jake on August 18, 2015

Upon stringing up my guitar with these (rather expensive) strings, the high E broke within 1 minute of breaking them in. I replaced it with a Regular Slinky .10 and carried on to see if the rest of the strings were any good.

In a nutshell, they weren't. In standard tuning on a 25" scale guitar (nothing crazy), the unwound strings do feel like they're stretching quite a bit. And after the first one broke for absolutely no reason, I had very little confidence in them to even perform normal string bends.

The wound strings are unusually and extremely grippy compared to any other strings I've played. I can't see any benefit to this. It makes sliding low notes and chords difficult, which is completely unnecessary.

These strings do have a notable odd scent to them which kind of put me off at first but isn't technically a drawback.

The one good thing I can say about the Cobalts is that they do, in fact, sound really good. They are unquestionably clearer-sounding and definitely sound better and stronger than standard Regular Slinky strings. But to me, that doesn't outweigh all the other annoyances of these strings.

Dont Buy These Just a Big Hype

By Abe from il on July 27, 2013 Music Background: Recording Engineer- Musician

These strings are just a big hype dont buy these. When I first got these they felt different than the regular Ernie ball strings. They felt really stiff. When I put them on they felt harder to bend than the regular ernie ball. They feel like they are about to break. The tone of these strings is bit brighter than other strings which for my taste is not good and they are not louder than other strings thats just a marketing scam. Just stick to the good old regular Ernie Ball strings they cost much less and they just work

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