Nagaoka MP-300 Phono Cartridge

Boron cantilever, elliptical diamond, and machined aluminum frame

The Nagaoka MP-300 combines a boron cantilever and 0.4 × 0.7 mil elliptical diamond with the machined aluminum frame used in the upper tier of the MP series. It retains the high-output Moving Permalloy generator and replaceable stylus architecture of the range while extending frequency response to 25 kHz.

Its 3 mV output is designed for a standard 47 kΩ MM phonostage, providing the low-moving-mass advantages of Nagaoka's MP system without requiring a moving-coil input or step-up device.

Moving Permalloy Generator

Nagaoka's Moving Permalloy design replaces the moving magnet of a conventional MM cartridge with a much lighter piece of magnetically permeable permalloy attached to the rear of the cantilever. The magnet and coils remain stationary in the cartridge body.

Reducing moving mass gives the cantilever greater freedom to respond to fine groove modulation while maintaining a useful high-output signal.

Boron Cantilever

The MP-300 uses a boron cantilever, combining low mass with very high stiffness. Its rigidity helps transmit the movement of the stylus to the generator without excessive flexure or stored mechanical energy.

Elliptical Diamond

The 0.4 × 0.7 mil elliptical diamond presents a narrower tracing radius to the groove than a conical stylus, allowing it to follow shorter-wavelength high-frequency modulation more accurately.

Machined Aluminum Frame

The MP-300 uses a machined aluminum frame to provide the generator and suspension with a rigid mechanical foundation. Nagaoka specifies channel separation of 25 dB at 1 kHz and channel balance within 1 dB.

Replaceable Stylus

The matching replacement is the Nagaoka JN-P300, retaining the elliptical diamond and boron cantilever.

What's Included

• MP-300 cartridge
• Stylus guard
• Mounting screws, washers, and nuts
• Non-magnetic screwdriver

Specifications

Type: Moving Permalloy stereo cartridge

Mounting: 1/2 in.

Stylus: 0.4 × 0.7 mil nude elliptical diamond

Cantilever: Boron

Output Voltage (At 1 kHz, 5 cm/sec): 3 mV

Frequency Response: 20 Hz–25 kHz

Channel Separation (At 1 kHz): 25 dB

Channel Balance (At 1 kHz): ≤1 dB

Dynamic Compliance (At 100 Hz): 7.2 × 10⁻⁶ cm/dyne

Vertical Tracking Force: 1.3–1.8 g

Load Resistance: 47 kΩ

Load Capacitance: 100 pF

Frame: Machined aluminum

Replacement Stylus: JN-P300

Weight: 7.8 g