00 × GNK00 Audio × GNK Audio

B&C S218BP subwoofer flatpack kit fully assembled - dual 18-inch drivers loaded, internal bracing, castors and Speakon connectors fitted

00 Audio × GNK Audio

CNC sub flatpacksfrom people who build speakers.

Precision-cut Baltic birch panels for low-stress assembly. Batch CNC runs share setup costs - giving you 142dB peak sub flatpacks from £750.

CNC’d right - no guesswork with a CNC shop that doesn’t know audio
UK-cut & QA’d - damaged panel? We’ll ship a replacement fast
Batch-run economics - shared setup savings passed on to you

Built to order

CNC Batch Pricing

Per cab. Final pricing confirmed at pre-order.

Batch 1 - Bulk rate pricing on all orders regardless of quantity

B&C Speakers

S218BP

Plans

2×18" 6th order bandpass

15mm Baltic birch ply142dB peak32Hz–80Hz (±3dB)1200×520×800mm

Flatpack only£900

Precision CNC-cut Baltic birch panels. Engineered for accurate, low-stress assembly. Build guide included.

2–3 units:£825 each4+ units (Bulk rate):£750 each

With hardware£1,000

Panels + connectors, handles, castors, fixings

2–3 units:£925 each4+ units (Bulk rate):£850 each

Unloaded, assembled£1,250

Built raw cabinet, hardware and damping fitted

Unloaded, finished£1,375

Built, finished with TuffCab (black or white), no drivers fitted

+ drivers

Loaded w/ 18DS100Base

£2,100

Finished cabinet with B&C 18DS100 drivers installed

Loaded w/ 18DS115Premium

£2,350

Finished cabinet with B&C 18DS115 neo drivers installed

18Sound

21" Manifold

Plans

2×21" manifolded bandpass

18mm Baltic birch ply146dB peak32Hz–80Hz (±3dB)1220×596×920mm

Flatpack only£1,050

Precision CNC-cut Baltic birch panels. Engineered for accurate, low-stress assembly. Build guide included.

2–3 units:£975 each4+ units (Bulk rate):£900 each

With hardware£1,150

Panels + connectors, handles, castors, fixings

2–3 units:£1,075 each4+ units (Bulk rate):£1,000 each

Unloaded, assembled£1,400

Built cabinet, hardware and damping fitted

Unloaded, finished£1,525

Built, finished with TuffCab (black or white), no drivers fitted

+ drivers

Loaded w/ 21LW1400Base

£2,500

Finished cabinet with 18Sound 21LW1400 drivers

Loaded w/ 21NLW9001Premium

£2,700

Finished cabinet with 18Sound 21NLW9001 neo drivers

Loaded w/ 21NLW9601Extreme

£2,850

Finished cabinet with 18Sound 21NLW9601 flagship neo

CNC Batch Information

Next cut date: TBC

Order deadline: TBC

Bulk rate pricing applies to 4+ units

Collection & Shipping

£50 per cabinet discount for local collection

Pallet shipping charged at cost

Got your own design? Request a custom quote

What's included?

Chop and change - order just what you need. We'll sort the rest.

Premium materials

Premium grade Baltic birch plywood, CNC-cut for strength and consistency.

Optional hardware pack

Handles, castors, connectors, screws, gasket tape, padding - skip the sourcing.

No fiddly cuts

Just glue and clamp. All precision cuts and dados done on CNC.

Build support

We'll tell you what tools you need, and support you through the build.

S218BP subwoofer flatpack kit - front view showing CNC-cut port structure and panel assembly

S218BP subwoofer cabinet - 18-inch drivers loaded with castors, handles, and Speakon hardware fitted

S218BP subwoofer flatpack - upright view showing internal bracing and bandpass port chambers

Who's behind this?

00 Audio

Brand, design, finishing, and operations. Building software for the DIY community and bringing quality audio experiences to music-led venues.

Website Instagram

GNK Audio

Decades of cabinet building and venue fit-out experience. In-house CNC, a high bar for quality, and a background touring and engineering for bands.

Instagram

Register your interest

Configure what you want below. We'll reach out to confirm final spec and pricing before taking deposits.

Batch 1 - Bulk rate pricing on all orders

Frequently asked questions

What is a flatpack?

A CNC-cut set of panels for a specific cabinet design, cut from birch ply and prepared for straightforward assembly. Panels are cut accurately so you get repeatable results without having to measure, route, or improvise.

What's included in the flatpack?

All CNC-cut wooden panels required to build the cabinet. Depending on the design, this can include internal braces, baffles, access panels, and any internal partitions required by the plan.

What's in the hardware pack?

We're still finalising the exact hardware selection, but it will include all necessary connectors, fixings and fittings (think connectors, screws, handles, castors and related mounting hardware). You'll receive a full itemised list before the deposit phase.

Do I need special tools to build it?

Minimal tools. You'll need glue, clamps, and a driver. We'll send a full recommended tool list and build notes before the deposit phase so you know exactly what you're signing up for.

Do you provide build instructions or support?

Yes. We'll provide build notes and practical guidance so you can assemble cleanly. If you get stuck mid-build, you can message us and we'll help you get unstuck.

Do you offer assembled or finished cabs too?

Yes. If you'd rather skip the workshop time, you can choose assembled or finished options depending on the design and batch.

Do you supply drivers as well?

Flatpacks are wood only. If you choose a "loaded" option (where available), it includes the cabinet plus drivers installed and ready to run.

Are these official B&C or 18Sound products?

No. These are third-party builds/flatpacks based on proven public designs and common driver pairings. We'll be clear about what each cabinet is designed around.

What material do you use?

Birch ply by default. If there are material options (for example thickness or grade), they'll be listed per product.

How does shipping work?

For large cabs, we typically ship via pallet. Flatpacks can often ship more easily than fully built cabinets. Shipping options and costs will be confirmed before you place a deposit.

What if I change my mind?

Change your mind? Return within 30 days in original packaging for a full refund.

What if my order arrives damaged?

If damaged in transit, we'll ship out replacement panels to you at no cost.

How do deposits and batches work?

We run small batches. You'll get full details (hardware list, tool list, lead time, delivery options) before the deposit phase. Deposits reserve a slot in the next batch.

Can I order just one, or do I need to buy a pair?

You can order a single, but most customers run pairs. If you're building a system, ordering two in the same batch helps keep everything consistent.

Can you customise things like connector position, handle type, or finish?

Sometimes, within reason. Small changes are easiest (connector plate style, handle choice, castor style). If you need custom dimensions or a modified design, that's usually a separate project.