Note: This article contains affiliate links. If you click on these links and make a purchase, I may earn a small commission at no extra cost to you. This helps support my research and content. Read my full affiliate disclosure here.
Upgrading the Kia Soul 6×8 speakers can noticeably improve clarity, bass response, and listening enjoyment during daily drives. Choosing the right set matters because even small differences in size, power handling, and mounting depth change how the speakers fit and perform in your vehicle. This guide lists our shortlisted top picks for 6×8 speakers that suit the Kia Soul. We evaluated candidates on sound quality, installation fit, and electrical compatibility to help you pick a practical upgrade. Read on for what to look for and which factors mattered in our selection.
Looking for other parts? See all Kia Soul parts & accessories.
Top Picks at a Glance
| Best Reviewed A top-rated pick with lots of positive feedback | Kenwood KFC‑C6866S 6×8 2‑Way Car Speakers (Pair) |  |
| Most Popular A crowd favorite that many people choose with confidence | MB Quart FKB168 6×8" 200W Coaxial Car Speakers (4-Pack) |  |
| Best Quality Built to a higher standard if you want something more solid | KICKER 6×8" CS Series Coaxial Speaker Upgrade Kit with Harness (4-pack) |  |
| Best Budget The cheapest option that still gets the job done reliably | Orion Cobalt Series CB683 6×8" 3-Way Coaxial Car Speakers (Pair) |  |
| Most Sold A high-volume bestseller chosen again and again | UTV Stereo 6×8" DS Series Coaxial Speaker Kit with Harness for Ford F-150 (4-Pack) |  |
| Best Value for Money The sweet spot between price and what you get | JBL GX8628 6×8" 2-Way Coaxial Car Speakers (Pair) |  |
| Best Overall The best all-around choice for most situations | Alphasonik AS268P 6×8-inch 3-Way Car Speakers (2 Pairs) |  |
1. Kenwood KFC‑C6866S 6×8 2‑Way Car Speakers (Pair)
| Speaker Type | Coaxial |
|---|---|
| Impedance | 4 Ohms |
| Power (Max/RMS) | 250W peak / 30W RMS |
| Tweeter Diameter | 1 Inches |
| Speaker Size | 8 Inches |
The Kenwood KFC-C6866S is a 6×8 two-way coaxial speaker pair intended as a direct replacement for factory 6×8 locations in vehicles like the Kia Soul. Each speaker uses a polypropylene/paper woofer for solid midbass and a 1-inch PEI balanced-dome tweeter for clearer highs, and the enlarged magnet circuit and sound field enhancer are tuned to improve clarity at typical car listening levels. These wired speakers are powered by the car stereo and are rated to handle up to 250 watts peak (30 watts RMS), which suits stock or slightly upgraded factory head units without an external amp. Installation is straightforward in most 6×8 openings, though some owners may need adapters or wiring connectors depending on the Soul's panel and harness. Practical benefits are better vocal presence, cleaner highs, and a simple upgrade path that keeps the stock radio; limitations are modest bass extension compared with component systems or powered subwoofers and the need for proper mounting adapters for some Kia Soul model years.
Best for: A reliability-focused buyer who wants a straightforward, factory-style speaker upgrade that improves clarity and durability without adding an external amplifier or complex installation.
Less Ideal for: Audiophiles seeking deep, room-shaking bass or owners planning a high-power aftermarket system who will need component speakers and a dedicated subwoofer instead.
- Clear high-frequency detail from 1-inch PEI balanced-dome tweeters
- Polypropylene/paper woofer provides improved midbass and midrange clarity over many stock speakers
- Fits standard 6×8 openings so installation is typically quick for a door or rear deck replacement
- Handles modest power levels safely with 4 ohm impedance for use on factory head units
- Not designed for deep bass so expect limited low-frequency output without a subwoofer
- May require speaker adapters or minor panel work for some Kia Soul years to achieve a flush, secure fit
Verdict A dependable, easy 6×8 replacement that sharpens mids and highs for Kia Soul owners who want a reliable factory-style sound upgrade.
2. MB Quart FKB168 6×8" 200W Coaxial Car Speakers (4-Pack)
| Speaker Type | Coaxial, Tweeter |
|---|---|
| Impedance | 4 Ohms |
| Speaker Maximum Output Power | 200 Watts |
| Woofer Diameter | 8.6 Inches |
| Tweeter Diameter | 1 Inches |
These MB Quart FKB168 6×8 coaxial speakers are a drop-in upgrade intended to replace factory speakers in vehicles like the Kia Soul. The set includes four speakers with aluminum dome tweeters, polypropylene cones, butyl rubber surrounds and a built-in 6 dB internal crossover for smoother transitions to the tweeter. In practice they deliver clearer highs and tighter midrange than many stock units, and the butyl surrounds and Kapton voice coil former improve durability and heat handling when fed by an aftermarket head unit or amp. They handle up to 200 watts peak (50 watts RMS per speaker) so pairing them with a modest 4-channel amp or a more powerful factory-replacement head unit will unlock better dynamics and bass presence. Limitations to expect are moderate sensitivity and midbass that benefits from an amp or enclosure support; in free-air door mounting they will not reproduce deep sub-bass. Also they do not include speaker grilles, so plan for protection if your Kia Soul installation exposes drivers to debris or contact.
Best for: A convenience-driven buyer who wants a straightforward, better-sounding factory replacement for a Kia Soul without vehicle modification and prefers quick installation and dependable daily performance.
Less Ideal for: Audiophiles seeking deep bass or maximum output without adding an amplifier or a subwoofer should look at component systems or powered subs instead.
- Drop-in 6×8 size designed for direct replacement in many vehicles including Kia Soul speaker openings
- Aluminum dome tweeters for clear, durable high frequencies
- Butyl rubber surrounds and Kapton voice coil former improve durability and thermal handling
- Integrated 6 dB internal crossover simplifies installation and ensures smoother tweeter integration
- Modest sensitivity and RMS power mean they perform best with a proper amplifier rather than a low-power factory head unit
- No included protective grilles are provided
- Limited deep bass output without a dedicated subwoofer or enclosure support
Verdict Solid, user-friendly 6×8 drop-in upgrade for a Kia Soul that gives clearer highs and tighter mids but performs best when paired with an amplifier or subwoofer.
3. KICKER 6×8" CS Series Coaxial Speaker Upgrade Kit with Harness (4-pack)
| Speaker Type | Coaxial |
|---|---|
| Impedance | 4 Ohms |
| Sensitivity | 90 dB |
| Peak Power (per pair) | 225 watts |
This KICKER bundle replaces stock 6×8 door speakers with CS Series 2-way coaxials and includes harnesses to simplify installation. It is designed to deliver clearer highs and tighter bass than many factory units by using PEI tweeters, a large woofer motor and UV-treated poly-foam surrounds for durability in a cab environment. The kit is typically used as a direct swap to upgrade a vehicle’s door speakers for more detail at highway volumes and stronger low-end without adding an amplifier. Notable features are the zero-protrusion tweeter for shallow mounting, extended voice coil technology for cleaner excursion, and included harnesses that plug into factory connectors for a quick, no-cut install. Practical benefits include a noticeable improvement in clarity and sensitivity compared with basic factory speakers and easier installation because of the harnesses. Limitations are that these are still passive coaxials so peak and sustained output depend on the head unit or amp used, and they may not replace a full component system if you want the highest separation or deepest sub-bass.
Best for: Performance-oriented buyers who want a clear, factory-like upgrade that improves detail and bass without a complex component system or aftermarket amp.
Less Ideal for: Buyers seeking an audiophile component setup with separate crossovers and speakers or those who need extreme low-frequency output without adding a dedicated subwoofer or amplifier.
- Designed as a vehicle-specific package with speaker harnesses for plug-and-play installation
- Zero-protrusion tweeters allow shallow mounting in tight factory locations
- CS Series design offers higher sensitivity and improved clarity over typical stock speakers
- UV-treated poly-foam surrounds and robust motor structure for heat and sunlight resistance
- Passive coaxial design limits highest-end separation and ultimate output without added amplification
- Some users may need to crimp or secure connections for long-term reliability
Verdict A high-sensitivity, vehicle-focused 6×8 upgrade that delivers clearer, punchier sound and easy installation but still benefits from additional amplification for maximum performance.
4. Orion Cobalt Series CB683 6×8" 3-Way Coaxial Car Speakers (Pair)
| Impedance | 4 Ohms |
|---|---|
| Peak Power | 280W |
| RMS Power | 70W |
| Frequency Response | 75Hz-20kHz |
| Sensitivity | 87.5 dB |
The Orion CB683 is a 6×8 3-way coaxial speaker pair built to upgrade factory sound in a simple, DIY-friendly install. Each speaker combines a polypropylene woofer, midrange and a tweeter in a single assembly, which reproduces low, mid and high frequencies without separate components. Orion rates the pair for 280W peak (70W RMS), 4-ohm impedance and an 87.5 dB sensitivity, so they play loud on most factory head units and benefit from an amplifier if you want cleaner headroom. The butyl rubber surround and polypropylene cone are durable and resistant to common cabin conditions, while the universal bracket-style mounting and included hardware speed installation into existing 6×8 openings. Expect noticeably stronger bass and clearer vocals compared with many stock Kia Soul speakers, though the small physical size and budget construction mean they will not match the punch or fidelity of high-end component sets or larger woofers. Also check fit and mounting depth for your Soul model because some customers have needed minor trimming or shims to seat the frame flush.
Best for: Budget-conscious owners looking to noticeably improve their Kia Soul's factory sound with an easy DIY upgrade and louder, fuller audio without buying amplifiers or component sets.
Less Ideal for: Audiophiles seeking top-tier clarity, deep bass, or component-level staging should consider component speakers or adding a dedicated woofer instead.
- 3-way coaxial design delivers fuller frequency coverage without external crossovers
- Up to 280W peak (70W RMS) handling for louder output than many factory speakers
- Durable polypropylene cone and butyl rubber surround for reliable in-car use
- Bracket mount and included hardware make installation straightforward for DIYers
- Not as powerful or detailed as component speakers or larger aftermarket woofers
- May require minor trimming or adjustment to fit flush in some vehicle openings
Verdict A budget-friendly 6×8 coaxial that delivers louder, fuller sound for a Kia Soul without complex installation, but it falls short of component-level fidelity.
5. UTV Stereo 6×8" DS Series Coaxial Speaker Kit with Harness for Ford F-150 (4-Pack)
| Speaker Type | Coaxial |
|---|---|
| Speaker Maximum Output Power | 200 Watts |
| RMS Power | 50 watts |
| Impedance | 4 ohms |
| Sensitivity | 90dB |
This bundle packages four 6×8" DS Series coaxial speakers with two vehicle-specific wiring harness pairs and basic trim tools to simplify a direct replacement install. The speakers are two-way coaxials with polypropylene cones, acoustic-foam surrounds, and a half-inch dome tweeter; the listing cites 50 watts RMS (200 watts peak) and 90 dB sensitivity, which helps deliver clear, source‑focused sound at typical car listening levels. The included harnesses claim to plug into factory connectors so you can avoid splicing, and the shallow top-mount depth reduces clearance issues behind door panels. In practice this kit is best for shoppers wanting a straightforward swap that improves clarity and mids compared with many aged factory speakers, while keeping installation simple. Limitations are modest bass extension versus a sub or larger woofer and variability in what's included with third-party bundles, so confirm the harness plug matches your vehicle before installing. The package is budget-friendly but oriented toward sound improvement rather than high‑powered bass performance.
Best for: Risk-averse buyers who prioritize a low‑hassle, factory-style speaker upgrade and want predictable sound improvement without complicated installation or amplifier installation.
Less Ideal for: Enthusiasts seeking deep, high-output bass or those wanting a custom high-power system should look at larger woofers, external amplifiers, or purpose-built subwoofers instead.
- Includes speaker harnesses for plug‑and‑play installation to avoid cutting or splicing
- Coaxial two‑way design with dome tweeter for clearer highs and improved vocal detail
- Shallow top-mount depth for easier fit behind door panels
- Bundle includes two pairs (four speakers) so front and rear doors can be upgraded together
- Spec'd RMS power and peak outputs are modest so bass will be limited compared with dedicated subwoofers
- Product is packaged for Ford F-150 fitment so harness compatibility with other vehicles may vary
Verdict A convenient, plug‑and‑play 6×8" speaker bundle focused on clear, reliable sound and easy installation rather than deep bass performance.
6. JBL GX8628 6×8" 2-Way Coaxial Car Speakers (Pair)
| Peak Power Handling | 180W each pair / 180W peak (360W per pair noted in description) |
|---|---|
| RMS Power Handling | 60W each / 120W per pair |
| Frequency Response | 50Hz – 21kHz |
| Sensitivity | 92dB @ 2.83V |
| Nominal Impedance | 2.3 ohms |
The JBL GX8628 pair replaces factory 6×8" speakers to deliver clearer highs and improved mid-bass for everyday driving in a Kia Soul. These coaxial speakers use a Plus One polypropylene woofer and an edge-driven soft dome tweeter with a proprietary tweeter deflector to push response up to 21 kHz, so vocals and instruments sound more detailed than typical stock units. They handle up to 180 watts peak (60 watts RMS each) and have a sensitivity around 92 dB, meaning they play loud enough from a factory head unit and accept additional power if you add a small amp. Installation is typically straightforward in vehicles that accept 6×8" replacements, and customers report cleaner sound and better presence without major modifications. Limitations are the modest continuous power rating for high-output builds and the lower nominal impedance that can draw more current from weak head units. Also they do not include installation hardware or wiring adapters, so some buyers will need connectors or brackets to complete the swap in certain Kia Soul model years.
Best for: Practical optimizers looking to cost-effectively improve Kia Soul cabin sound quality without major system changes and who prioritize reliable, balanced upgrades over audiophile power builds.
Less Ideal for: Buyers planning a high-power, competition-level system or those who want a plug-and-play kit with adapters and mounting hardware included should look for purpose-built components or full installation kits.
- Clear high-frequency detail from the edge-driven soft dome tweeter
- Plus One woofer cone improves mid-bass compared with typical stock speakers
- High sensitivity makes them loud enough with a factory head unit
- Individually voiced drivers for balanced sound across frequencies
- Modest RMS power rating limits extreme high-volume or heavily amplified systems
- No installation hardware or wiring adapters included
Verdict A practical, factory-quality 6×8" speaker upgrade for Kia Soul owners who want clearer highs and tighter mid-bass at a strong value, as long as they do not need high-power output.
7. Alphasonik AS268P 6×8-inch 3-Way Car Speakers (2 Pairs)
| Speaker Type | 3-Way Speaker |
|---|---|
| Impedance | 4 Ohms |
| Sensitivity | 92 dB |
| Frequency Response | 28 – 22,000 Hz |
| Included Components | 4x Speakers, Coaxial Cables, Mounting Screws, Installation Manual |
These Alphasonik AS268P speakers are a four-piece 6×8-inch, 3-way coaxial kit intended to replace factory door speakers and lift in-car clarity and volume. They are typically used as a direct upgrade to stock systems, driven by a factory head unit or modest aftermarket deck; the kit includes mounting screws and pigtail leads to simplify installation. Notable features include a claimed 350W max per speaker (35W RMS per speaker), a 28–22,000 Hz frequency range and a 92 dB sensitivity rating, which together suggest they will deliver louder output than many OEM units without an external amp. Real-world benefits are clearer vocals, stronger midrange presence and improved perceived bass compared with base-model speakers, and reviewers report easy bolt-in installs for many vehicles. Limits are typical for an economy 3-way set: low-end extension is modest so drivers wanting deep bass will still need a subwoofer, and peak power claims are not the same as sustained RMS power, so heavy amplification may stress the drivers. Build quality is good for the price but not on par with premium competition.
Best for: Balanced buyers who want a straightforward, value-minded full-range upgrade to their Kia Soul's factory audio that improves clarity and volume without adding amps or major modifications.
Less Ideal for: Audiophiles seeking deep, punchy bass or competition-grade sound staging should look at higher-end component speakers and a dedicated subwoofer instead.
- Includes four speakers plus mounting screws and pigtail leads for easier installation.
- 92 dB sensitivity and wide frequency claim that helps louder output from a stock head unit.
- 3-way coaxial design improves vocal clarity and high-frequency detail compared with typical factory speakers.
- 35W RMS per speaker provides limited sustained power and modest bass without an external amplifier.
- Not water resistant so exposure to moisture in door cavities could affect longevity if doors are not sealed well.
Verdict A budget-friendly 6×8 3-way kit that noticeably beats stock speakers for clarity and volume but will need a sub or amp for real low bass.
Choosing the Right Kia Soul 6X8 Speakers: Key Factors to Consider
Physical Fit and Mounting Depth
Correct physical fit is the first practical constraint. Speakers that match the Kia Soul's 6×8 footprint and have an appropriate mounting depth avoid the need for door trimming or spacer rings. Too shallow and you lose performance; too deep and the speaker may hit internal hardware or window mechanisms. Check mounting hole pattern, overall frame diameter, and cutout dimensions before purchase. Also consider included mounting brackets or adapters because those simplify installation and can secure a stable speaker-to-door seal, which affects bass performance and reduces rattles.
Power Handling and Sensitivity
Power handling tells you how much amplifier power a speaker can safely accept and sensitivity indicates how loud it will play from a given input. For many Kia Soul installations the factory head unit or amplifier delivers modest power, so pairing speakers with appropriate sensitivity avoids underdriven, muddy sound or the temptation to crank volume and introduce distortion. Choose speakers whose RMS rating matches or slightly exceeds the head unit's continuous output, and favor higher sensitivity if you plan to run on stock power. Avoid expecting high-power ratings to improve sound unless you also upgrade the amplifier.
Frequency Response and Tonal Balance
A speaker’s frequency response gives a general idea of its ability to reproduce lows, mids, and highs. In door-mounted 6×8 speakers, achieving controlled bass is more challenging than with larger woofers, so prioritize models that offer a balanced midrange and clear highs to preserve vocal and instrument detail. Consider whether the speaker emphasizes bass or midrange and how that interacts with the rest of your car audio system. A flatter response often translates to more natural sound, while a bass-boosted signature can sound exciting but may mask detail at higher volumes.
Coaxial Versus Component Design
Coaxial 6×8 speakers combine tweeter and woofer in one assembly, making installation simpler and saving dash or door space. Component 6×8 setups separate the tweeter from the woofer, allowing more precise placement and typically better imaging and clarity, but they require additional mounting locations and potentially crossovers. Decide based on how much installation complexity you can accept and whether improved stereo imaging and treble detail are important to you. In many factory door locations, coaxial speakers provide a strong balance of ease and performance.
Build Quality and Weather Resistance
Car door speakers are exposed to temperature swings, humidity, and dust. Materials such as treated cones, durable surrounds, and corrosion-resistant frames extend speaker life. Weather resistance matters more if you frequently park outdoors or live in humid climates. Inspect specifications for materials that resist deterioration and look for sealed tweeters or protective grills that help prevent moisture ingress. Better build quality reduces risk of mid-term failure and maintains consistent performance over years of use.
Installation Hardware and Compatibility
Accessible installation hardware and clear fitment instructions reduce installation time and mistakes. Standardized mounting holes, included screws, and adapters can eliminate the need for additional purchases or custom brackets. Compatibility with factory wiring harnesses or the availability of plug-and-play adapters also simplifies the process. Consider whether the speakers require new crossovers, splicing, or modifications to the factory connector. The less custom wiring required, the quicker and more reversible the upgrade, which is helpful for owners who want a clean installation without permanent changes.
FAQ
Can I install 6×8 speakers in the Kia Soul without modifying the doors?
Often you can, provided you choose speakers with matching mounting dimensions and shallow enough mounting depth. Many aftermarket 6×8 speakers are designed for direct-fit installations, but it depends on the exact model year and factory speaker location. Check mounting hole patterns and clearance for window mechanisms before purchase.
Do I need a new amplifier to run upgraded 6×8 speakers?
Not always. If you select speakers with sensitivity and RMS power handling suited to your factory head unit or amp, you can get a noticeable improvement without adding amplification. However, if you pick speakers designed for high power or with low sensitivity, an aftermarket amp will be necessary to realize their full potential.
Are coaxial 6×8 speakers a good option for everyday listening?
Yes. Coaxial 6×8 speakers provide a convenient balance of ease of installation and improved tonal quality over worn stock units. They integrate a tweeter and woofer in one assembly, which usually gives better clarity and dynamics for everyday music listening without complex mounting.
How important is speaker impedance when replacing 6×8 speakers?
Impedance matters because it affects how the speaker loads the head unit or amp. Matching the replacement speakers to the vehicle’s electrical system helps ensure efficient power transfer and reduces the risk of amplifier strain. Most car audio systems use 4-ohm speakers, but you should verify the Kia Soul's specification for your model year.
Will replacing 6×8 speakers improve bass in the Kia Soul?
You can often get tighter and clearer bass by upgrading the door-mounted 6×8 speakers, but their small size limits low-frequency extension compared with larger subwoofers. Expect improved mid-bass and overall clarity, while deep, room-shaking bass typically requires a dedicated subwoofer or enclosure.
How We Chose the Best Kia Soul 6X8 Speakers
We focused on speakers that specifically meet the physical and electrical constraints typical of the Kia Soul speaker locations. Our editorial filters prioritized correct mounting dimensions, reasonable mounting depth for factory doors, and compatible impedance so the factory amplifier or head unit can drive the speakers without excessive distortion. We assessed sonic performance using criteria like frequency response balance, midrange clarity, and bass extension relative to enclosure and door placement. Durability factors included cone material and weather resistance for door-mounting. Installation ease and availability of mounting hardware or adapters were also important since complex modifications reduce appeal for most owners. Excluded items were any speakers that required major door trimming, custom enclosures, or significant electrical modification. We also excluded products that lacked clear fitment specifications for the Kia Soul or that did not provide standard mounting dimensions and depth information.
Our full evaluation process is outlined in our review methodology.
Conclusion
When choosing Kia Soul 6×8 speakers prioritize correct physical fit, appropriate power handling, and a tonal balance that matches your listening preferences. Pay attention to mounting depth, sensitivity, and the tradeoff between coaxial convenience and component-level imaging. Focus on speakers that meet your installation constraints and sound goals. Properly matched speakers will deliver clearer vocals, tighter mid-bass, and a more enjoyable in-car listening experience without unnecessary modification.
Explore More:
- Check out all Kia Soul parts & accessories
- Explore Electronics
- Browse all Accessories
