Ninjai Woofer · Audio Edition

Feel the
music.

A precision acoustic chamber, fired in stoneware, tuned to 40Hz. The home hub that moves air.

From €699
100W
RMS Output
35Hz
F3 Bass Limit
112dB
Peak SPL at 1m
18mm
Ceramic Wall
40Hz
Tuning Frequency

The material

Why ceramic
changes everything.

Every speaker enclosure resonates. Wood, MDF, plastic — they all flex, absorb energy, and add a character to the sound you didn't ask for. Ceramic doesn't.

High-fire stoneware has a resonant frequency well above the audio band. The walls don't vibrate sympathetically with the music. At 100W, the enclosure stays acoustically silent — only the air moves, only the driver speaks.

The cobalt glaze that gives the base its International Klein Blue finish is integral to the material — not painted on. The colour and the acoustic properties are fired together at 1280°C. One object, no compromises.

🎯
Resonant frequency above audio band The ceramic walls ring at frequencies your ears can't hear. Below 20kHz, the enclosure is effectively silent — all the acoustic energy stays in the music.
⚖️
Mass kills resonance Stoneware is 2.4× denser than MDF. Heavier enclosures are consistently better sounding — it's why audiophile speakers weigh absurd amounts. Physics, not marketing.
💧
Naturally airtight Fired ceramic is hermetically sealed without compounds or gaskets. Predictable internal air volume means precisely calculable acoustic behaviour — every unit identical.
🔷
Integral bracing ribs Three horizontal ribs are cast into the mould and fired as part of the form. No glued joints, no flex. The enclosure is as rigid as the geometry allows.
🎨
Cobalt IKB glaze Reduction-fired cobalt blue at 1280°C produces a depth of colour that no painted surface can match. The Ninjai blue is in the clay, not on it.

Acoustic Engineering

The interior
architecture.

Technical cross-section at 1:5 scale. Every internal dimension is calculated from acoustic first principles — Helmholtz resonator theory, passive radiator tuning equations, and driver parameter matching.

Front Elevation — Section A–A

36cm height 32cm base width Rib 1 Rib 2 Rib 3 20cm 100W driver Passive radiator + mass Electronics · CPU · WiFi Section A–A · 1:5 scale · cm

Side Elevation — Section B–B

20cm depth Passive radiator 18mm wall FRONT REAR Section B–B · 1:5 scale
Why a passive radiator, not a port
A conventional bass reflex port for this enclosure volume, tuned to 40Hz, would require a tube 4.6 metres long — physically impossible to fold into the base. A passive radiator (a second cone with no magnet, tuned by a bolt-on mass disk) achieves identical acoustic behaviour with no tube at all. This is how KEF, Bose, and most premium compact speakers solve this exact problem. The tuning frequency is adjusted at manufacture by the weight of the mass disk — making each ceramic unit acoustically identical despite natural firing shrinkage variation. The rear-facing radiator also creates an omnidirectional bass field, filling the room from every direction rather than projecting forward.
External dimensions
32 × 20 × 36
W × D × H cm · revised for acoustics
Net acoustic volume
~7.5 litres
After driver + electronics displacement
Enclosure type
Passive radiator
No port tube · ceramic-compatible
Active driver
8-inch / 20cm
Front face · 100W RMS · Qts 0.3–0.4
Passive radiator
8-inch / 20cm
Rear face · tunable mass disk · Fb ≈ 40Hz
Tuning frequency
~40 Hz
Musical, tight bass · F3 at ~35Hz
Wall thickness
18mm
High-fire stoneware · acoustically inert
Internal bracing
3 ribs
Integral ceramic · cast into mould
Glaze
Cobalt IKB
Reduction fired 1280°C · matches #002FA7
Peak SPL
108–112 dB
At 1m · 90dB/W/m driver sensitivity
Damping
20mm foam
All non-driver interior faces
Electronics bay
Top section
Acoustically isolated · sealed ceramic shelf

How it works

The passive radiator
explained simply.

1
The active driver pushes air
The 100W driver on the front face moves forward and backward, creating pressure waves inside the sealed ceramic chamber. At bass frequencies, this internal pressure builds rapidly.
2
The passive radiator responds
On the rear face, a second cone — with no magnet, no motor — responds to the internal pressure. It moves in sympathy, radiating bass into the room from behind. This doubles the effective radiating area without doubling the power.
3
The mass disk controls tuning
A small ceramic disk bolted to the passive cone adds mass. More mass = lower tuning frequency. This is set at manufacture to exactly 40Hz — below this, the system rolls off gently rather than catastrophically.

Inside the Woofer

Origami paper shade Hand-folded washi Ceramic neck mount Cable channel · WiFi antenna Electronics bay CPU · WiFi 6E · Bluetooth Acoustically isolated Rib 1 Rib 2 Rib 3 18mm stoneware walls Cobalt IKB glaze · 1280°C 3 integral bracing ribs 8-inch driver 100W RMS Front-firing 8-inch passive radiator Tunable mass disk Rear-firing · Fb = 40Hz 4× USB-C (3.2 Gen 2) 2× USB-A · Power in Speaker expansion jack
01 — Overview
Seven components.
One object.
The Ninjai Woofer is an engineered acoustic system disguised as a lamp. Scroll to explore each layer — from the origami shade to the port connectors at the base.
02 — Origami Shade
Hand-folded.
Acoustically transparent.
Washi paper, folded over a wire frame. The folds allow sound from the electronics neck to pass through without obstruction. The shade is the only component that doesn't affect the acoustic chamber.
MaterialWashi paper
Fold techniqueHand-folded
Light transmission~60%
03 — Electronics Bay
Sealed above.
Silent below.
The top section of the ceramic enclosure houses all electronics — CPU, WiFi 6E, Bluetooth, and the 100W Class D amplifier. A ceramic shelf seals it from the acoustic chamber. Electronics never touch the sound.
ProcessorQuad-core ARM
WirelessWiFi 6E · BT 5.3
Amp classClass D · 100W
04 — Ceramic Body
Fired at 1280°C.
Acoustically inert.
High-fire stoneware with three integral bracing ribs cast into the mould. The walls ring at frequencies above the audio band — the enclosure adds zero coloration. At 100W, the ceramic stays completely rigid while wood would flex.
Wall thickness18mm
Firing temp1280°C
GlazeCobalt IKB
Internal volume7.5 litres
05 — Active Driver
100W. Front-firing.
20cm cone.
An 8-inch long-throw woofer sits flush in the front face. The ceramic mounting surface is rigid enough to prevent the driver from rocking — a common failure mode in MDF cabinets at high power. The voice coil and magnet assembly are rated for continuous 100W operation.
Diameter20cm / 8-inch
Power (RMS)100W
Sensitivity90dB / W / m
Qts0.3 – 0.4
06 — Passive Radiator
Rear-firing.
Tuned to 40Hz.
A second 8-inch cone on the rear face — no magnet, no motor. It responds to the internal air pressure created by the active driver, radiating bass in all directions. The ceramic mass disk bolted to the cone is calibrated at manufacture to tune the system to exactly 40Hz.
TypePassive radiator
Tuning freq40 Hz
F3 point~35 Hz
DirectionRear-omnidirectional
07 — Connectivity
Everything.
At the base.
All ports are recessed into the rear face near the base — invisible from the front, accessible from behind. Four USB-C ports handle data and power delivery simultaneously. The speaker expansion jack connects satellite speakers with a single cable.
USB-C4× USB 3.2 Gen 2
USB-A2× USB 3.0
Power in100–240V
Speaker out3.5mm expansion
Scroll to explore

Ready to order

Ninjai Woofer.

Ceramic enclosure. 100W passive radiator system. Tuned to 40Hz. International Klein Blue.

€699