Xcelsus XP620 Primum 6.5" 2 Way Coaxial System
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Everything Must Go Pricing
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Trade Show Display Models
Many items are pristine display models from major audio trade shows - equipment that's been seen but never installed. These pieces often include special editions or limited releases not available through regular retail channels.
Xcelsus XP620 Primum 6.5" Coaxial Speakers
Designed by the Inventor of the Component Speaker System
The Inventor's Final Coaxial Design
The Xcelsus XP620 Primum represents something extraordinarily rare in car audio: a discontinued coaxial speaker designed by the man who invented the component speaker system itself. Dawid Koniarski—co-founder of DLS in 1979 and the engineer who in 1983 created the world's first automotive component speaker system—poured over four decades of acoustic expertise into this innovative design before Xcelsus discontinued the Primum series.
These are brand new, factory-sealed units from remaining stock—never installed, never used, complete with original packaging and accessories. Once this inventory is exhausted, the XP620 Primum will be gone forever, making this your last opportunity to own a piece of car audio history at closeout pricing.
The Man Behind the Design: Dawid Koniarski
In 1979, Dawid Koniarski co-founded DLS (Dynamic Loudspeaker Systems) in Sweden alongside his friends Stefan and Leif. While Dawid and Leif worked as high-frequency technicians building police scanners, Stefan managed production logistics and administration. This partnership would eventually revolutionize car audio forever.
The breakthrough came in 1983. Dawid had just purchased a new Volvo but found the factory sound system deeply disappointing. After testing numerous premium coaxial speakers from top brands of the era, he remained unsatisfied. One day, while listening to his home stereo speakers, a realization struck him:
The Component Speaker Epiphany
"I looked at my home speakers and it hit me—I said to myself, if the coaxial was the ultimate solution, then they would have used them in home Hi-Fi speakers, right?"
The very next day, Dawid visited an electronics parts shop and purchased Philips drivers for televisions and Audax polyimide tweeters. He designed a simple crossover, installed the system in his Volvo, and discovered the sound was better than all the coaxials he had tested before.
"This, to the best of my knowledge, was the origin of the component speaker system that you are familiar with in the car audio market today." — Dawid Koniarski
Four Decades of Competition Dominance
Dawid's designs didn't just change the industry—they dominated it. His speakers became the weapon of choice for sound quality competitors worldwide:
- IASCA Competitions: Dawid's drivers achieved championships across Europe, Sweden, and internationally
- EMMA Championships: His USA team, led by Keith Doney, secured multiple second places as USA and World Champions, featuring legends like Scott Buwalda and "Eddy the Jesus"
- International Success: Dawid's designs earned World Champion titles from Thailand competitors Mr. Buck and Mr. Pong at EMMA European and USA Championships
- Global Reach: Champions emerged using his speakers in Russia, South Africa, Australia, China, Philippines, Thailand, Indonesia, Malaysia, and beyond
From 1979 until February 2016, Dawid served as Chief Speaker Designer at DLS, creating legendary products that set benchmarks for sound quality worldwide. When DLS's new owners unexpectedly retrenched him in 2016 after 37 years, Dawid founded Xcelsus Audio, bringing his uncompromising design philosophy to a new brand where he could work with a small, dedicated specialist team.
The XP620 Philosophy: Rethinking Coaxial Design
While Dawid invented the component speaker system in 1983, he never abandoned coaxial development. The XP620 Primum represents his solution to a fundamental problem: modern vehicles mount speakers deep behind doors and trim panels, severely dampening treble response from traditional coaxial designs.
The design premise was ambitious: create a coaxial speaker that delivers rich, full sound at an affordable price while solving the treble-attenuation problem that plagues factory locations. The solution? An innovation not commonly seen in competing brands: dual 16mm Mylar dome tweeters in a forward-mounted array configuration.
The result is not just a speaker that impresses on a demo board, but one that excels in the real-world acoustic environment of your vehicle—where it truly matters.
Technical Specifications
| Specification | Value |
|---|---|
| Model | XP620 Primum |
| Series | Primum Series (DISCONTINUED) |
| Configuration | 2-Way Coaxial |
| Woofer Size | 6.5" (16.5 cm / 165mm) |
| Tweeter Configuration | Dual 16mm (0.63") Mylar dome tweeters |
| Tweeter Magnet Structure | Neo-magnet array (neodymium) |
| Tweeter Mounting | Forward-mounted dual array |
| Woofer Cone Material | Polypropylene with mica fill |
| Power Handling (RMS) | 50W |
| Power Handling (Max) | 80W |
| Impedance | 4Ω (ohms) |
| Frequency Response | 50 Hz - 20,000 Hz |
| Sensitivity | 92 dB (1W/1m) |
| Crossover Type | Integrated MXP capacitor crossover |
| Crossover Slope | 6 dB/octave (first-order) |
| Outer Diameter | 165mm (6.5") |
| Mounting Hole Diameter | 145mm (5.7") |
| Mounting Depth | 52mm (2.0") - shallow mount |
| Magnet Size | 80mm (3.15") diameter |
| Weight (per speaker) | 2.4 kg (5.3 lbs) for pair |
| Condition | Brand New (Factory Sealed, New Old Stock) |
| Status | DISCONTINUED - Limited remaining inventory |
Dual 16mm Tweeter Array: Engineering Breakthrough
The Problem: Factory Location Treble Attenuation
Modern vehicle design prioritizes aerodynamics, safety, and interior aesthetics over acoustic performance. The result? Speakers are increasingly mounted in challenging locations:
- Deep Behind Door Panels: Door-mounted speakers sit 2-4 inches behind plastic trim, grilles, and speaker covers
- Off-Axis Positioning: Factory locations rarely point directly at listeners—speakers aim at feet, knees, or door pockets
- Obstructions: Window switches, door handles, armrests, and interior trim create acoustic barriers
- Absorption Materials: Sound-deadening materials and door panel fabric absorb high frequencies preferentially
Traditional single-tweeter coaxials suffer dramatically in these environments. High frequencies (above 5 kHz) are highly directional and easily absorbed by materials. A single tweeter struggling to overcome door panel absorption simply can't deliver adequate treble energy to the listening position.
The Solution: Dual Tweeter Array with Neo-Magnet Structure
Dawid's XP620 design addresses treble attenuation through dual 16mm Mylar dome tweeters in a forward-mounted array configuration. This isn't simply adding a second tweeter—it's a sophisticated acoustic solution:
Doubled Acoustic Output
Two tweeters radiating coherently produce approximately +3 dB higher output than a single tweeter (doubling acoustic power). This 3 dB advantage compensates for door panel absorption, maintaining treble energy at the listening position.
Extended Frequency Response
Dual tweeters distribute the workload, allowing each dome to operate more comfortably within its linear range. This extends usable high-frequency response and reduces distortion at typical listening levels compared to a single tweeter working harder.
Improved Power Handling
Two voice coils share thermal load, improving power handling and reliability. When one tweeter might reach thermal compression (reduced output due to heat), dual tweeters maintain consistent performance at higher volumes.
Neo-Magnet Efficiency
Neodymium magnets provide 3-5× stronger magnetic field than ferrite magnets of equivalent size. This allows compact 16mm tweeters to achieve high efficiency (92 dB sensitivity) while maintaining low mass for excellent transient response.
Forward-Mounted Array Configuration
The XP620's dual tweeters aren't simply positioned side-by-side—they're configured in a forward-mounted array that came about after extensive real-world testing in various factory locations. This mounting strategy provides several advantages:
- Directivity Control: The array pattern focuses high-frequency energy forward, minimizing off-axis losses to door panel sidewalls
- Phase Coherence: Closely-spaced tweeters (16mm centers) remain within coherent summing distance through the critical 2-10 kHz range, avoiding comb-filtering issues
- Reduced Sensitivity to Obstructions: Dual sources provide some acoustic redundancy—if one tweeter's path is partially blocked, the second maintains treble output
- Visual Balance: The symmetric array appears intentional and premium, unlike single off-center tweeters that can look like afterthoughts
Mylar Dome Material Selection
Dawid specified Mylar (biaxially-oriented polyethylene terephthalate) dome material for the XP620's tweeters—a deliberate choice based on four decades of tweeter design experience:
- Low Mass: Mylar is extremely lightweight (typical dome weighs <0.1 gram), allowing rapid acceleration and excellent transient response for crisp, detailed highs
- Self-Damping: The polymer structure provides inherent mechanical damping, reducing resonances and breakup modes that color treble response
- Temperature Stability: Mylar maintains consistent mechanical properties across the -40°C to +100°C temperature range common in automotive environments
- Fatigue Resistance: Unlike metal domes that can work-harden and crack under repeated flexing, Mylar exhibits excellent long-term durability
- Smooth Response: Properly designed Mylar domes produce smooth, extended high-frequency response without the ringing and harshness that can plague metal domes
Polypropylene Mica-Fill Woofer: Balanced Performance
Material Science for Midbass Accuracy
The XP620's 6.5" woofer employs polypropylene cone material with mica mineral fill—a composite approach that balances competing requirements of stiffness, damping, and mass:
Polypropylene Base
Polypropylene provides the base polymer matrix, offering excellent moisture resistance, temperature stability (-40°C to +100°C automotive range), and fatigue resistance for long-term reliability in harsh vehicle environments.
Mica Mineral Fill
Mica particles distributed throughout the polypropylene matrix increase cone stiffness without proportionally increasing mass. This raises the cone's breakup frequency (where bending modes begin), extending smooth response through the critical 1-3 kHz midrange.
Optimized Damping
The polypropylene/mica composite provides internal damping that controls cone resonances. Pure metals or pure polymers can ring at specific frequencies; the composite structure dissipates vibrational energy as heat.
Manufacturing Consistency
Injection-molded mica-filled polypropylene produces highly consistent cone geometry and material properties from unit to unit—critical for left/right channel matching in stereo imaging.
52mm Shallow Mounting Depth
At just 52mm (2.0") mounting depth, the XP620 fits virtually any factory 6.5" location without clearance issues. This shallow profile is achieved through several design optimizations:
- Compact Magnet Structure: The 80mm diameter magnet provides strong magnetic field within minimal depth envelope
- Optimized Voice Coil Gap: Precision machined gap between pole piece and top plate maximizes magnetic flux efficiency without excessive depth
- Integrated Dual Tweeter Array: Tweeters mount within the woofer basket structure rather than adding external depth
- Flush-Mount Terminals: Connection terminals recess into basket structure, preventing protrusion beyond mounting plane
This 52mm depth accommodates factory locations in door panels, kick panels, rear decks, and dashboard positions where deeper aftermarket speakers simply won't fit. If your factory speakers fit, the XP620 will fit—guaranteed.
92 dB Sensitivity: Amplifier-Friendly Efficiency
The XP620's 92 dB sensitivity rating (1W/1m) represents excellent efficiency for a 6.5" coaxial speaker. This means the XP620 produces 92 decibels of sound pressure level when driven with just 1 watt of power, measured at 1 meter distance.
Why High Sensitivity Matters:
- Factory Head Unit Compatibility: Most factory head units produce 15-22 watts RMS per channel. With 92 dB sensitivity, the XP620 reaches 104-106 dB maximum SPL from factory power alone—plenty loud for most listeners
- Amplifier Efficiency: If you add an aftermarket amplifier, high sensitivity means less power required to reach target volume levels, allowing smaller, more efficient amplifiers
- Reduced Thermal Stress: Less power input for equivalent output means less heat generation in voice coils, improving reliability and longevity
- Dynamic Headroom: With 50W RMS handling and 92 dB sensitivity, the XP620 can reach ~109 dB maximum SPL—sufficient for enthusiast listening levels without distortion
50W RMS Power Handling
The XP620 is rated for 50 watts RMS continuous power (80 watts maximum short-term). This conservative rating reflects Dawid's design philosophy: specify honest, sustainable power handling rather than inflated marketing numbers.
50W RMS is appropriate for:
- Factory Systems: Most factory head units produce 15-22W RMS—well within the XP620's capabilities
- Entry-Level Amplifiers: 50W×4 channel amplifiers (common configuration) match perfectly
- High-Power Head Units: Aftermarket head units rated 22-30W RMS provide excellent performance without risk
The 80W maximum rating allows brief musical peaks and transients above the 50W continuous rating without damage, providing dynamic headroom for percussion, bass kicks, and other high-energy musical content.
Integrated MXP Crossover: Elegant Simplicity
First-Order 6 dB/Octave Topology
The XP620 employs an integrated MXP capacitor crossover with 6 dB/octave slope—a first-order high-pass filter that allows the dual tweeters to roll in gently above the woofer's natural rolloff point. This simple topology offers several advantages in coaxial applications:
Minimal Phase Shift
First-order filters introduce only ±45° maximum phase shift, compared to ±90° (second-order) or ±135° (third-order). Minimal phase shift preserves time-domain accuracy, maintaining transient coherence between woofer and tweeters.
Smooth Power Response
Gentle slopes allow significant overlap between woofer and tweeter response, creating smooth summed power response. Steeper slopes can create dips or peaks at crossover frequency due to phase interactions.
Simplified Parts Count
First-order crossovers use minimal components (single high-quality MXP capacitor), reducing insertion loss, cost, and potential failure points. Fewer parts mean higher reliability over years of thermal cycling in vehicle environments.
Component Quality Focus
With only a single capacitor in the signal path, Dawid could specify premium MXP (metallized polypropylene) film capacitors known for low ESR (equivalent series resistance), excellent temperature stability, and long-term reliability.
Why MXP Capacitors?
The choice of MXP (Metallized Polypropylene) film capacitors rather than cheaper electrolytic types reflects attention to sonic quality:
- Low Dielectric Absorption: MXP capacitors exhibit minimal dielectric absorption (energy storage in dielectric material), reducing distortion and maintaining signal transparency
- Temperature Stable: Capacitance value remains consistent from -40°C to +105°C, ensuring crossover point doesn't shift with temperature
- Self-Healing: Metallized film construction provides self-healing properties—if localized breakdown occurs, the metallization vaporizes around the fault, isolating it without catastrophic failure
- Long Lifespan: MXP capacitors maintain performance for decades, unlike electrolytic capacitors that can dry out and fail within 5-10 years in automotive heat
Installation Excellence & Vehicle Compatibility
Universal 6.5" Fitment
The XP620's standard 6.5" mounting dimensions ensure compatibility with the vast majority of vehicles using 6.5" (165mm) factory speakers:
| Dimension | Measurement | Compatibility Note |
|---|---|---|
| Outer Diameter | 165mm (6.5") | Standard 6.5" speaker size |
| Mounting Hole | 145mm (5.7") | Fits standard 6.5" cutouts |
| Mounting Depth | 52mm (2.0") | Shallow mount—fits nearly all factory locations |
Compatible Vehicle Applications:
- Front Doors: Most common 6.5" location—ideal for XP620's dual tweeter array aimed at listeners
- Rear Doors: Excellent rear fill application, shallow depth accommodates tight door panel clearances
- Rear Deck: 52mm depth fits shallow rear deck installations in sedans and coupes
- Kick Panels: Custom kick panel installations benefit from shallow depth and high sensitivity
- Dashboard: Fits factory 6.5" dash locations when present (less common but possible)
Factory Integration Scenarios
Factory Head Unit Upgrade
Scenario: Keep factory head unit, upgrade speakers only
Benefit: 92 dB sensitivity means XP620 achieves excellent volume from factory 15-22W power. Dual tweeter array overcomes door panel absorption in factory locations. Maintains steering wheel controls, factory integration.
Aftermarket Head Unit + Speakers
Scenario: Aftermarket head unit (22-30W) + XP620 speakers
Benefit: Increased power drives XP620 to higher clean output levels. Better source quality (less compression, better DAC) reveals XP620's transparency and detail. Simple direct connection, no amplifier required.
Budget Amplified System
Scenario: Entry-level 4-channel amplifier (50W×4) + XP620
Benefit: Perfect power match to 50W RMS rating. Achieves maximum XP620 output potential (~109 dB SPL). Improved damping factor from amplifier enhances bass control. Total system cost remains budget-friendly.
High-Power Amplified System
Scenario: Premium amplifier (75-150W×4) + XP620
Benefit: Use amplifier's gain control to limit power to safe 50W RMS levels. Massive headroom means amplifier never strains, reducing distortion. Excellent for enthusiasts who may upgrade speakers later while keeping amplifier.
Installation Tips & Best Practices
- Orientation: Orient speakers so dual tweeter array aims toward primary listening positions (usually inward and upward from door locations)
- Sound Deadening: Add CLD (constrained layer damping) tiles to door panels behind speakers to reduce panel resonance and improve midbass punch
- Vapor Barrier: Install vapor barrier (plastic sheet) between speaker and door inner structure to create proper sealed rear chamber for bass response
- Wiring: Use minimum 16-gauge speaker wire for runs up to 15 feet, 14-gauge for longer runs. Maintain polarity (+/+, -/-) for proper imaging
- Grilles: Factory grilles are fine, but aftermarket perforated metal grilles reduce high-frequency absorption compared to fabric grilles
Discontinued Status: Last Chance Opportunity
New Old Stock Explained
These XP620 Primum speakers are New Old Stock (NOS)—a term meaning:
- Brand New: Never installed, never used, never opened
- Factory Sealed: Original factory packaging intact with all accessories
- Old Stock: From discontinued production run, not current production
- Full Functionality: Mechanically and electrically identical to when originally manufactured
Speakers, unlike electronics, don't suffer from component aging when stored properly. Mica-filled polypropylene cones, Mylar tweeter domes, rubber surrounds, and MXP capacitors remain stable for decades when protected from UV exposure and extreme temperatures. These NOS units will perform identically to when they were first manufactured.
Why Discontinued?
Xcelsus discontinued the Primum series (including XP620) as part of a product line rationalization, focusing resources on their higher-end series where Dawid's expertise commands premium pricing. The Primum series represented Xcelsus's entry-level offering—affordable speakers with genuine engineering pedigree.
This doesn't mean the XP620 was deficient. Rather, Xcelsus chose to position themselves in premium markets where Dawid's legendary reputation and four decades of design experience justify higher price points. The discontinuation creates an exceptional opportunity: speakers designed by a legend, priced as closeout inventory.
Limited Remaining Inventory
These are the final remaining units from original Primum series production. Once this inventory is exhausted:
- No additional XP620 Primum speakers will be manufactured—ever
- Xcelsus has confirmed no plans to reintroduce the Primum series
- Secondary market prices for NOS units will likely increase as rarity grows
- This is your last opportunity to purchase brand new units at closeout pricing
Collectibility & Historical Significance
Beyond their sonic performance, XP620 Primum speakers represent a unique piece of car audio history: affordable coaxials designed by the inventor of the component speaker system. As Dawid's final mass-market coaxial design before Xcelsus focused exclusively on premium products, these speakers carry historical significance that will only increase with time.
For collectors, historians, and enthusiasts who appreciate the lineage behind their equipment, NOS XP620 speakers represent the last chance to own an affordable piece of Dawid Koniarski's 40+ year design legacy.
The Inventor's Legacy at Closeout Pricing
In 1983, Dawid Koniarski looked at his home speakers and realized coaxials weren't the ultimate solution. The very next day, he created the world's first automotive component speaker system—an innovation that redefined car audio forever. For 37 years at DLS and now at Xcelsus, his designs have dominated sound quality competitions on every continent.
The XP620 Primum represents Dawid's final mass-market coaxial design before Xcelsus discontinued the affordable Primum series. These brand new, factory-sealed speakers showcase his solution to modern vehicles' acoustic challenges: dual 16mm Mylar tweeter array with neo-magnet structure, overcoming door panel treble absorption through doubled acoustic output and forward-mounted array configuration.
The mica-filled polypropylene woofer delivers accurate midbass. The 92 dB sensitivity drives loud from factory head units. The 52mm shallow mount fits virtually anywhere. The 50W RMS power handling matches entry-level amplifiers perfectly. The integrated MXP crossover provides elegant simplicity and long-term reliability.
This is discontinued inventory at closeout pricing. Once these final units are sold, the XP620 Primum will be gone forever—no restock, no reproduction, no second chances. Brand new speakers from a discontinued product line, designed by the man who invented component speakers, available at a fraction of their original value.
Experience acoustic engineering from the inventor himself. Own a piece of car audio history before it disappears. Upgrade your factory speakers with legendary design pedigree.
New Old Stock. Discontinued Forever. The Inventor's Legacy.
Xcelsus XP620 Primum 6.5" 2 Way Coaxial System
Frequently Asked Questions
Are these items authentic, and why are the prices so low?
This sale includes demo units we've used for customer demonstrations since 2016, new-old-stock from discontinued product lines, display models from trade shows, and carefully curated inventory we've collected over nearly a decade. Most items include original packaging where available.
What types of items are included in the relocation sale?
Our relocation sale includes demo units we've used for customer demonstrations, new old stock from discontinued product lines, and display models from trade shows. All items are genuine products from top car audio brands - we're simply clearing inventory we can't take to our new location. Items range from amplifiers and speakers to processors and accessories accumulated over nearly 10 years at this location.
Do sale items come with manufacturer warranties?
Warranty coverage varies by item and condition. New old stock items typically include full manufacturer warranty if still valid. Demo and display items may have limited or no manufacturer warranty remaining. We clearly state warranty status in each product description. All sales are final on relocation sale items.
How does shipping work for relocation sale items?
We ship relocation sale items using the same careful packaging methods as our regular inventory. Shipping costs are calculated at checkout based on size and weight. For multiple item purchases, we'll combine shipping where possible to save you money. Large items like subwoofer boxes may require freight shipping with additional costs.
Can I return or exchange relocation sale items?
All relocation sale items are sold as-is with no returns or exchanges. We encourage local pickup customers to inspect items before purchasing. For shipped items, we provide detailed descriptions and photos. Since we're relocating, we cannot accommodate returns or warranty service after the sale period ends.