Roadster‑grade bass. OEM look.

Frequently Asked Questions (FAQ)

1. What is this subwoofer enclosure designed for?

Our custom 3D-printed enclosure is specifically designed to replace the weak factory subwoofer in the BMW Z3 Roadster. It fits perfectly into the original factory location with no cutting or major modifications required, delivering superior bass performance tailored to the car’s acoustics.

2. What is the enclosure volume?

The Stealth Box features a volume of 5.3 litres, optimized for 6.5” subwoofers to deliver tight and impactful bass.

The Big Box features a volume of 11.05 litres, optimized for 6.5” subwoofers to deliver maximum output.

3. What subwoofers can I choose from?

We offer three carefully selected 6.5” subwoofer options, each including wiring and professional installation:

• SWS Earthquake 6.5X: 100W RMS, 4Ω — great power with low distortion.

• Helix IKW6 DVC 2 Ohm: 150W RMS, Dual 2Ω — our recommended model for deep, controlled bass.

• JL Audio 6W: 150W RMS, 4Ω — premium clarity and punch, great for discerning listeners. (Not compatible with Stealth Box)

4. Is the subwoofer installation included?

Yes! Every subwoofer installation includes:

• A proprietary airtight seal to prevent air leaks for maximum bass efficiency.

• Pre-installed with matching black screws for a factory-like appearance.

• Enclosure tuning to ensure your sub sounds exactly as intended.

• Full installation instructions provided.

5. How long is the lead time?

These are handmade, custom products. Please allow approximately 2.5 weeks for production and quality assurance before shipment.

6. Can I add sound deadening or other upgrades?

Absolutely. We offer premium add-ons to enhance your system’s performance and durability:

• Premium Acoustic Fill — fine-tunes bass response.

• Sound Deadening (Full Wrap) — Recommended for loud music enthusiasts, this greatly reduces vibrations and distortion at high volumes.

• Oversized Mesh-Wrapped Speaker Cable (16 ft) — for clean, noise-free rewiring from amp to speaker.

• Weather-Resistant Upgrade — essential insurance for humid, wet, or hot climates, featuring thicker gaskets, mold-resistant fill, and protective coating to protect your enclosure from the elements.

7. Are there cosmetic upgrades available for the Big Box?

Yes, we offer Big Box-exclusive luxury wrap options:

• Vegan Leather Lid Wrap (UV resistant) — durable and stylish.

• Premium Marine Leather Wrap (Black or Beige) — weather-resistant and refined.

8. What about Seatbelt Guide Retainer Clips?

Our clips protect your seatbelt guides from cracking by reinforcing them.

• Priced at $29 with an optional $40 shipped version including North America shipping.

9. Can I buy a subwoofer enclosure only?

Yes, but our packages are designed to include professional installation with an airtight seal and quality screws to ensure maximum performance.

10. Do you provide amplifier recommendations?

Yes! Upon ordering, you can request a list of recommended amplifiers perfectly matched to your chosen subwoofer and enclosure.

11. What are the shipping options and costs?

• North America: $49–$69

• Europe: €49–€69

• Australia: $79

12. How do I place an order?

Click the "Order Now" button on the product page or complete the order form available at www.z3subwoofer.com. For any questions or custom requests, email us at BMWZ3Enclosure@gmail.com.