Early this year Ernie Ball released a unique line of electric guitar and bass strings. Known as Cobalt Slinkys. The proprietary cobalt steel wrap on the wound strings is said to be provide a “stronger magnetic relationship between the strings and the pickups”, resulting in higher output, more sustain, and richer harmonics. The initial response was so strong that Ernie Ball were left scrambling to keep pace with the demand. I recently got my hands on a set and put them through their paces.

EB Cobalts

The first thing you notice when taking Cobalts strings out of the package is the colour. The wound strings are obviously different. They have a dull, matte finish, and a darker grey colour than you’ll be used to seeing, with just a hint of  of blue. Are they pretty? No, but they don’t need to be! By the way, the new cobalt alloy is only used for the wrap on the wound strings and not used on the plain strings, which are the same tin-coated high-carbon steel that you’ll find in any pack of Ernie Ball Slinkys.

Once installed on my guitar, I noticed that Cobalts felt a little ‘rougher’ than I’m used to. Compared to a standard EB Slinky, the Cobalts have a slightly bigger wrap on slightly smaller core resulting in fewer wraps per unit length. It’s not a big difference but our finger tips are sensitive enough to feel it. That extra roughness bothered me a little at first. It’s not bad, it’s just different and I got used to it pretty quickly.

As a result of the smaller core, the Cobalts also have a slightly lower tension than regular wound strings of a similar gauge. The difference here was less than I expected, quite subtle actually, but after a short time playing I suddenly realised that I wasn’t fighting the wound strings any more. They were just a little more pliable, a little slinky-er. Once I got used to the rougher feel, these are the most comfortable strings I’ve ever played. They feel great!

EB Cobalt close up

Cobalt string (top), standard Slinky (bottom), both strings are 0.042″. Note the slightly larger winding on the Cobalt string.

Tonally, Cobalts strings have a deeper bass response, a different mid-range focus, and more upper treble content. It reminds me a little of changing strings on an acoustic guitar from 80/20 bronze to Phosphor Bronze.  There is more depth and ‘zing’. It’s a great mix of power and clarity. The shifted mid-range gives them a tone that I would describe as slightly scooped, in fact it’s almost piano-like on the lowest notes. The extra volume is obvious, yet subtle and doesn’t overpower the plain strings.

With distortion the deeper bass is still present and gives power chords a great depth and ‘chunk’. There is more definition and harmonics and more clarity to notes and chords. Pinch- and tapped-harmonics jumped off these strings with an ease that had me grinning from ear to ear. It’s a lot of fun! I think distortion players will love these strings.

I had these strings on for just over a week. In that time,  I played two three-hour rehearsals, a two-hour gig,  and about 10 hours of practice at home. The tone of the Cobalt strings stayed bright and clear far longer than I expected from an uncoated string. At the end of that week, their sound had dulled a little but they still sounded as bright as the fresh set of standard Slinkys that I put on after. That impressed me.

I love the comfort and feel of the Cobalts, and I love the harmonics with distortion. Obviously, I can see rock and metal players loving these strings but I can see country and jazz players really digging them too. These are comfortable, responsive, great sounding strings and I really enjoyed them. Despite that, I’m going back to the Coated Super Slinkys. It was a tough call but I prefer the mid-range structure of the normal Slinkys more than I’ll miss the feel and harmonics of the Cobalts.

At the end of the day, electric guitar strings sound pretty similar no matter where they come from. Cobalts don’t offer a huge tonal change that, say, changing amplifiers will give, but they do offer a new flavour to guitarists in the never-ending quest for “the ultimate tone”. While tone and feel are entirely subjective and Cobalts won’t suit everyone, I do think everybody should try them out. Even if you don’t like them, they’ll certainly make you think about how strings function in the chain of tone that starts with your pick or fingers and ends at the speaker. That’s always a good thing.

Edit: (Jan 30, 2013) Some people have been asking so just to clarify – Cobalt strings are slightly lower tension than standard slinkys, confirmed by EB (in case you didn’t take my word for it all ready).

3 comments on “Ernie Ball Cobalt Strings Review

  1. DrKev

    There is a different balance between the wound and plains strings, yes, but I won’t call it an ‘issue’, because is it of course a personal thing. A small adjustment to the pickups is a good idea (perhaps raising the treble side a little, or lowering the bass side) and we can always tweak our tone a little by raising or lowering pickups, something many people overlook. That should be a future post. Thanks for your comment!

  2. ernie ball

    “Excellent read, I just passed this onto a friend who was doing some research on that. And he actually bought me lunch as I found it for him smile So let me rephrase that: Thanks for lunch!”

  3. Anthony J. Anderson

    honestly, i have tried close to every brand of strings. while the cobalts have longer life than other Ernie Ball Bass Strings, i dont think that they stay alive longer than say an elixer. but still wonderful feel, wonderful tone, wonderful string.

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