What is the primary material used in Ernie Ball 2731 strings?

These strings are wrapped with a proprietary cobalt-iron alloy. This material is selected for its high magnetic permeability compared to traditional nickel-plated steel.

What are the specific gauges in the Power Slinky 2731 set?

The set includes four strings with gauges of .055 (G), .075 (D), .090 (A), and .110 (E). This is considered a 'Power' gauge, which is heavier than standard sets.

How does Cobalt technology affect the volume of the bass?

Cobalt strings are engineered to maximise output by creating a stronger magnetic relationship with the pickups. This results in a louder, more powerful signal being sent to the amplifier.

Are these strings suitable for 5-string basses?

The 2731 set is a 4-string set. While the individual strings can be used, a 5-string bass would require an additional low B or high G string not included in this specific pack.

Do Cobalt strings feel different to the touch?

Yes, many players find that Cobalt strings have a unique feel that is slightly 'softer' or more flexible than stainless steel, despite their high output. They provide a smooth surface that is comfortable for the fingers.

What kind of tone can I expect from the Cobalt Power Slinky set?

Expect an extended dynamic range with increased low-end punch and very clear, crisp high frequencies. The harmonic response is also significantly enhanced.

How do these compare to Ernie Ball M-Steel strings?

M-Steel (like the 2921 set) uses a Maraging Steel core for maximum strength and output on guitars, whereas the Cobalt Slinky line focuses on the wrap wire alloy to enhance the magnetic response for both guitar and bass.

Are these strings durable for heavy playing?

The Power Slinky gauge (.055-.110) is specifically designed for durability and a heavier tension. The cobalt wrap is also resistant to corrosion, potentially extending the life of the string's brightness.

Can I use these strings for slap bass?

Yes, the increased clarity and high-end response make them very effective for slap bass. The .055 G string provides a substantial snap and presence.

What is the typical price for the Ernie Ball 2731 set?

The typical price range for this specific Cobalt bass set is approximately £32.00. This reflects its status as a premium innovation in the Ernie Ball catalogue.

Will these strings fit a short-scale bass?

The 2731 set is designed for long-scale basses (34 inches). Using them on a short-scale bass may result in the thick part of the string wrapping around the tuning post, which is not recommended.

Do these strings require special pickups?

No, they are designed to work with all standard magnetic bass pickups. They simply enhance the performance of the pickups already installed on your instrument.

Gear article

Ernie Ball Power Slinky 2731 Cobalt Bass Guitar Strings

The Ernie Ball Power Slinky 2731 Cobalt Bass strings are a high-output set designed for four-string electric basses, featuring a gauge range of .055 to .110. They utilise a proprietary cobalt-iron alloy wrapping to provide enhanced magnetic response and an expanded frequency range compared to traditional nickel or stainless steel strings.

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Background and Innovation

Ernie Ball introduced the Cobalt Slinky range as a significant innovation in string technology, moving beyond the standard nickel-plated steel and stainless steel formulations that have dominated the market for decades. The development focused on the magnetic relationship between the strings and the instrument's pickups. By using a cobalt-based alloy, the manufacturer aimed to provide a 'new voice' for the instrument, specifically engineered to maximise output and clarity for modern playing styles.

Technical Specifications

The 2731 Power Slinky set is characterized by its heavy gauge profile, consisting of .055, .075, .090, and .110 diameter strings. The core is typically a hex-shaped high-carbon steel, wrapped with a cobalt-iron alloy. This specific alloy is chosen for its superior magnetic properties, which interact more efficiently with the magnetic fields of bass pickups than traditional materials. This results in a stronger signal and a broader dynamic range.

Sonic Character

The primary tonal characteristics of the Cobalt Slinky series include an increased low-end presence and crisp, clear highs. The harmonic response is notably improved, allowing for more complex overtones to be captured by the amplifier. Players generally report a higher output level, meaning the strings can drive an amplifier harder at the same volume settings compared to standard nickel strings. The 'Power Slinky' gauge specifically adds a sense of weight and tension that suits aggressive playing styles.

Comparison and Alternatives

Within the Ernie Ball ecosystem, the 2731 Cobalt set sits as a premium high-output alternative to the standard Nickel Power Slinky sets. While other specialized strings like the M-Steel 2921 or Tim Henson Signature sets cater to specific guitar requirements, the Cobalt Bass series is dedicated to low-end fidelity. Outside of the bass world, brands like D'Addario offer the Zyex or Helicore series for orchestral instruments, which use different materials like synthetic cores or tungsten to achieve specialized tension and tone, whereas the Cobalt Slinky remains focused on electromagnetic enhancement for electric instruments.

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Frequently asked questions

What is the primary material used in Ernie Ball 2731 strings?: These strings are wrapped with a proprietary cobalt-iron alloy. This material is selected for its high magnetic permeability compared to traditional nickel-plated steel.
What are the specific gauges in the Power Slinky 2731 set?: The set includes four strings with gauges of .055 (G), .075 (D), .090 (A), and .110 (E). This is considered a 'Power' gauge, which is heavier than standard sets.
How does Cobalt technology affect the volume of the bass?: Cobalt strings are engineered to maximise output by creating a stronger magnetic relationship with the pickups. This results in a louder, more powerful signal being sent to the amplifier.
Are these strings suitable for 5-string basses?: The 2731 set is a 4-string set. While the individual strings can be used, a 5-string bass would require an additional low B or high G string not included in this specific pack.
Do Cobalt strings feel different to the touch?: Yes, many players find that Cobalt strings have a unique feel that is slightly 'softer' or more flexible than stainless steel, despite their high output. They provide a smooth surface that is comfortable for the fingers.
What kind of tone can I expect from the Cobalt Power Slinky set?: Expect an extended dynamic range with increased low-end punch and very clear, crisp high frequencies. The harmonic response is also significantly enhanced.
How do these compare to Ernie Ball M-Steel strings?: M-Steel (like the 2921 set) uses a Maraging Steel core for maximum strength and output on guitars, whereas the Cobalt Slinky line focuses on the wrap wire alloy to enhance the magnetic response for both guitar and bass.
Are these strings durable for heavy playing?: The Power Slinky gauge (.055-.110) is specifically designed for durability and a heavier tension. The cobalt wrap is also resistant to corrosion, potentially extending the life of the string's brightness.
Can I use these strings for slap bass?: Yes, the increased clarity and high-end response make them very effective for slap bass. The .055 G string provides a substantial snap and presence.
What is the typical price for the Ernie Ball 2731 set?: The typical price range for this specific Cobalt bass set is approximately £32.00. This reflects its status as a premium innovation in the Ernie Ball catalogue.
Will these strings fit a short-scale bass?: The 2731 set is designed for long-scale basses (34 inches). Using them on a short-scale bass may result in the thick part of the string wrapping around the tuning post, which is not recommended.
Do these strings require special pickups?: No, they are designed to work with all standard magnetic bass pickups. They simply enhance the performance of the pickups already installed on your instrument.