Kondo Audio Note Japan Kagura 2i Power And Overture PM 2i Integrated Amps

NEW KONDO AUDIO NOTE JAPAN KAGURA 2I POWER AND OVERTURE PM 2I INTEGRATED AMPLIFIERS RELEASED

Kondo Audio Note Japan has released two new amplifiers, the Kondo Kagura 2i Power Amplifier and Kondo Overture PM 2i Integrated Amplifier.

KONDO AUDIO NOTE JAPAN KAGURA 2I POWER AMPLIFIER

The Kondo Audio Note Japan Kagura 2I is a parallel single ended monaural power amplifier.

The Kondo Kagura 2I’s circuit design is configured with 12AU7～6SN7 x2 for amplification and 6SN7 x2 (cathode follower) for the driver stage to powerfully drive the large-scaled transmitter 211 tube.

Kondo Audio Note Japan Kagura 2i Power And Overture PM 2i Integrated Amps — Kondo Audio Note Japan Kagura 2i Power Amps

These circuits are independently powered by large-scale and low impedance power supply sections supporting high purity amplification stages. In order to attain the prime audio quality expected from a Kagura, each stage has been re-examined and newly developed.

POWER SUPPLY CIRCUIT

There is a total of 3 power supply transformers used in the amplifier; B power supply transformers above the rear section of the chassis, and amplifying heater transformers and rectifier heater transformers inside the chassis. Four choke coils are installed to form three system power supply circuits with four different voltages +/-200V, +450V, and +950V. The power supply section features oil capacitors rated at 1000V and newly developed cut-core type choke coils; Two power cables are supplied with one unit of Kagura due to the fact that main power supply and heater power supply are separated from the AC inlet.

MODULARIZED UNITS

By modularizing the voltage amplifying section, Kondo has employed manual wiring and shortening of paths. By placing three system decoupling capacitors quite near each module, high purity signal loops could be formed in each stage.

211 OUTPUT TUBES

Compactly arranged 211 output tubes and the near heater peripheral section are placed near the amplification unit so that from the first stage tube to output tube base could be stowed in a compact space eventually minimizing the wiring length to the furthest tubes. The 211 heather circuit is mounted with large capacitors (40000uF x2) to minimize ripple elements while residual noise level has been reduced with the use of a hum balancer circuit.

HIGH GRADE PARTS

Between the amplification stages Kondo employed newly developed electrode oscillation proof silver foil capacitors. Instead of conventionally used EI core choke coil, Kondo have developed a new cut-core type of choke for an improvement in sound quality. Kagura’s pure silver coiled output transformer handles output impedances of 4, 8 and 16Ω. The setting is preset for 4Ω and 8Ω for speaker impedance in the factory.

KONDO AUDIO NOTE JAPAN KAGURA 2I POWER AMPLIFIER SPECIFICATIONS

Product: 211 parallel single ended monaural power amplifier

Model: Kagura 2I

Rated power: 50W @1kHz, 5% THD

Frequency response: 8Hz ～ 55kHz (+0dB, -3dB @1W)

Input / Impedance: RCA x1(unbalanced) / 70kΩ,

XLR x1(unbalanced, 2:HOT) / 70kΩ

Output: 4Ω, 8Ω, 16Ω (2 outputs factory preset)

Noise: Less than 0.5mV

Vacuum tubes: 211 x2, 6SN7 x2, 12AU7 x1, GZ34 x4

Power consumption: 270W

Dimension: 320mm(W) 370mm(H) 558mm(D) (excluding protrusions)

Weight: 62kg

KONDO AUDIO NOTE JAPAN OVERTURE PM 2I INTEGRATED AMPLIFIER

Kondo applied a new design guideline of “Cleaner with more Triode Splendidness” for the new Overture Integrated amplifier. This was refined through extracting the knowledge that they learned from the Kagura research and development.

NEW OUTPUT TRANSFORMER

A new output transformer was designed for higher sound quality, introducing a third winding exclusively for NFB. The circuit has been redesigned and retuned and the power supply section has been heavily improved and re-laid out for better channel separation. An improved version of Kondo’s original silver foil signal capacitors has been used.

Power tubes are the pentode EL34. Output impedance is selectable 4Ω and 8Ω.

NEW DESIGN PUSH-PULL CIRCUIT

The first stage and driver stage are both direct coupling circuits. Pure silver foil capacitors are used as coupling in the output stage. Kondo aimed to make the entire circuit low impedance so that a transparent and direct sound is achieved. There is also a newly design circuitry CCB (constant current biasing) adopted in the output stage. It prevents music signal from flowing into the bias adjustment VR and maintain music signal’s purity and integrity. The output transformer is a UL connection and the wiring is all arranged so that shortest paths and best performance are obtained.

POWER SUPPLY

The high reserve power supply circuit is constructed with choke coils and large capacitors. After the ripple filter stage, the decoupling capacitors are further arranged to serve left and right channels independently.