Description item

KORG Nu: tekt HA-S (new)

Tube sound everywhere

HA-S is a high-quality portable headphone amplifier DIY (self-made) kit equipped with Nutube. No soldering is required, even beginners can assemble it immediately, and you can enjoy your favorite music with high sound quality.


Make a headphone amplifier with your own hands
The HA-S DIY kit does not require any soldering, making it easy and fun to make headphone amplifiers. What's more, this amp provides a genuine tube sound that audiophiles will love.


Nutube installed
Nutube is a fully analog next-generation vacuum tube jointly developed by KORG and Noritake Itron. Nutube is made up of an anode, grid, and filament, just like a traditional tube, and acts as a complete triode. Nutube provides the same rich overtone characteristics as traditional tubes in a smaller, more stable and energy efficient way. Light and compact, the HA-S case design allows the Nutube light to show through, making it the perfect choice for carrying high-quality audio.


Energy Conservation
By using a DC-DC converter, it efficiently converts when generating filament power from a battery. This reduces current consumption and improves battery life. But there is no compromise in sound. HA-S can generate a 26V line voltage to drive Nutube with just two AA batteries, and realize a rich and authentic vacuum tube sound!


Possibility of timbre
The HA-S is equipped with an NFB (negative feedback) switch. With this switch, you can switch between a clean and clear sound with high sound quality and a warm, overtone-rich vacuum tube sound.

When the negative feedback switch is OFF, the circuit becomes a circuit without feedback, the overtones of Nutube (triode) are enhanced, and a richer sound with a stronger vacuum tube color is generated. Turning on the NFB switch reduces distortion and overtones for a more "hi-fi" sound.

Two types of output stage operational amplifiers are included to change the sound. There are two types, the JRC premium audio-oriented "MUSES 01" and the orthodox "NJM4580". These can be easily replaced with IC sockets.

In addition, a circuit diagram is included for customization. If you change the parts to higher sound quality parts, you have infinite possibilities to easily create your own headphone amplifier that matches the desired tone and performance.


Specifications Specifications
■ Vacuum tube: Nutube 6P1

■ Connection terminal: INPUT / OUTPUT terminal Stereo mini phone jack
■ Control: Volume, NFB switch (internal)

■ Output impedance: 10Ω, recommended load 15Ω or more

■ Power supply: 2 AA alkaline batteries (sold separately)
■ Battery life: Approximately 9 hours (when using alkaline batteries)

■ External dimensions: 111 (width) x 65 (depth) x 29 (height) mm
■ Mass: 110 g (excluding batteries)

■ Accessories: Manual