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NF04R Active Speaker


The NF04R is an active speaker with a built-in amplifier that enhances the reproduction capabilities and expresses rich musicality of small-sized speakers.

It features dual amplification drivers for both the woofer and tweeter. Additionally, it is equipped with a filtering function that effectively corrects low frequencies, allowing you to adjust the bass according to the installation position. The speaker also includes XLR/TS combo jacks as input terminals, enabling you to connect balanced signals (+4dBu) or unbalanced signals (-10dBV) from mixers and other devices.



I thought it was excellent as a near-field speaker. The quality of vocals and other sounds is really good. They have a distinct presence and clarity. The only thing I feel is lacking is a bit more of the deep bass, but I suppose that's understandable given its size. On the other hand, I'm quite impressed by the fact that it produces such impressive sound from such a compact size.

Powerful Bass and Compact Design

The NF series features a compact 4-inch (10cm) HR-shaped woofer unit, delivering tight, high-speed, and surprisingly deep bass that surpasses its size. With the adoption of "UDR Tangential Edge" and "Push-Pull Damper," it eliminates reverse resonance in the edge, ensuring excellent linearity and a responsive mid-low range.

High-Fidelity Reproduction and Responsive Performance

The NF series introduces a UFLC soft dome tweeter that exhibits high responsiveness and fidelity even with delicate audio signals. The soft dome design ensures accurate reproduction of intricate details, while the implementation of magnetic fluid in the magnetic circuit enables stable operation over extended periods of use.

Powerful Amplification for Enhanced Audio Performance

The NF series features a high-performance D-Class amplifier, delivering 30W for the woofer and 20W for the tweeter, enabling efficient and powerful driving of the speaker units in a bi-amp configuration.

Customizable Sound Pressure Level and Gain Adjustment

The NF series introduces adjustable sound pressure levels to suit different listening environments. It allows for adjusting the bass level by -2dB, -4dB, or -6dB, and the tweeter level by -2dB. Additionally, it offers a GAIN switch for matching the output level of external audio devices, with options for 0dB or +10dB.

Enhanced HR Diaphragm Design

The HR (HP Rotation) shape, known in the field of architectural structural mechanics, is an improved version of the HP (Hyperbolic Paraboloidal) shape achieved by incorporating rotational elements along the circumference. This shape experiences shear forces as internal stress, eliminating bending stress and resulting in a lightweight structure with high rigidity. Additionally, it disperses resonance caused by divided vibrations, making it an ideal shape for the diaphragm.

Exceptional Fidelity with UFLC Diaphragm

The UFLC (Ultra Fine Layered Construction) diaphragm, made of polyurethane resin with a polyurethane film laminated on a cloth material, is employed in the high-frequency tweeters of this device. By utilizing this diaphragm, it becomes possible to faithfully reproduce audio signals with natural extension into the high-frequency range.

Revolutionary UDR Tangential Edge

The UDR (Up/Down Roll) Tangential Edge is an innovative edge structure that combines upward and downward rolls using a tangential surface. Its shape is optimized based on FEM (Finite Element Method) modal analysis to maximize the functionality of the edge. This groundbreaking edge design is employed in the woofers, which play a crucial role in the speaker's performance.

SN04 Speaker Grill (Optional)

The SN04 Speaker Grill is designed specifically for the NF04R model. It features a high-precision resin-molded frame and a robust steel punching grill.

  • The high-precision resin-molded frame ensures a perfect fit.
  • Cushion materials are strategically placed on the inner side to provide stability and prevent rattling during installation.
  • The grill can be easily removed and attached without the need for screws.
  • Suitable for various applications in relay stations, halls, and other audio equipment settings.
EB-6301 Wall Mount Bracket (Optional)

The EB-6301 Wall Mount Bracket enables angle adjustments and wall installation for speakers.

  • Adjustable angle for the speaker body to achieve the desired sound projection.
  • Constructed with a robust 3mm thick iron plate for durability and stability.



2 way bass reflex type


100mm HR shape woofer
19mm soft dome tweeter

Frequency Response

57Hz - 36kHz

Internal volume


Output power

Woofer: 30W, Tweeter: 20W


Balanced:XLR-3-31 type (No. 2 HOT)
Unbalanced:φ 6.3 mm (1/4”) TS phone

Input level

-10dBV (TS phone) / +4dBu (XLR) GAIN SW 0dB
-20dBV (TS phone) / -6dBu (XLR) GAIN SW +10dB

Input impedance

20kΩ or more


– ∞ ~ 0dB


0 / -2 / -4 / -6dB

Tweeter level




External dimensions

(W)120 × (H)189 × (D)157mm
*Excluding protrusions


Approximately 3.1kg

Power supply (AC IN)

220V to 50/60Hz

Power consumption



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