MB Quart XK2-108 3.5-Inch 2-Way Coaxial Speaker System - Compact

Our review of the MB Quart XK2-108 3.5-in coaxial speakers finds them best suited for drivers who want a clear, punchy upgrade in cramped installation locations. The single biggest reason to buy is the combination of 70 watts RMS power handling and an 88dB sensitivity that together deliver surprisingly dynamic sound from a very compact package. These are not full-size replacements for large door speakers, but they shine where space is limited and clarity matters.

Key Features

• High power handling: 70 watts RMS and 140 watts peak per pair mean the speakers can handle louder playback without obvious strain in typical car systems.
• Wide frequency response: The 55Hz to 22kHz range preserves bass fundamentals and high-frequency detail for balanced everyday listening.
• Good sensitivity: An 88dB rating helps the speakers play decisively even with modest factory head units or low-power amps.
• Compact dimensions: The 3.5-in diameter, 3.41-in cut-out and 1.5-in depth from the flange make these easy to fit in tight factory locations.
• Durable construction: Built from quality materials for reliable, longer-term performance in a vehicle environment.
• Versatile compatibility: Designed to upgrade a wide range of car audio systems without complex modification.

Who It's For

The XK2-108 is ideal for owners of compact cars, motorcycles with fairing speaker spaces, or any vehicle where factory openings are small and a clean installation is a priority. It serves listeners who value clear mids and highs, and who want better performance than stock speakers without adding large speakers or significant power.

Drivers seeking deep sub-bass or full-range door speakers with large cone area should look elsewhere; while the frequency range starts at 55Hz, these are best paired with a separate subwoofer or larger component speakers for very low bass impact.

Pros & Cons

Pros

• Compact size makes them straightforward to install in tight factory locations.
• High power handling and good sensitivity deliver energetic playback with limited amplification.
• Wide 55Hz-22kHz response provides clear highs and usable low-mid extension.

Cons

• Limited cone size means bass will be less full than larger speakers; a subwoofer is recommended for deep bass lovers.

Specifications

Speaker type	3.5-in 2-way coaxial
Power handling	70W RMS / 140W peak per pair
Sensitivity	88dB
Frequency response	55Hz - 22kHz
Cut-out diameter	3.41 in
Mounting depth	1.5 in from flange

Our Verdict

The MB Quart XK2-108 delivers a compact, well-balanced sound upgrade for vehicles with limited speaker space. Choose these if you need reliable, clear midrange and treble, and pair them with a sub if you want stronger bass-they represent good value for anyone prioritizing fit and clarity over deep low-end output.

Frequently Asked Questions

Will these fit in small factory openings?
Yes, the 3.41 in cut-out diameter and 1.5 in depth from the flange make them suitable for many tight factory openings.

Can I drive these with a factory head unit?
Yes, the 88dB sensitivity helps them perform well with low-power factory head units, though an amp will improve dynamics.

Do these produce deep bass?
They extend down to 55Hz but, due to their small cone size, deep bass is limited; a dedicated subwoofer is recommended for full low-end impact.