Improvement

 

New design guideline "Cleaner with more Triode Splendidness" was refined through extracting the knowledge we learned from Kagura researches and applications.

 

• New output transformer was designed for higher sound quality. By introducing a 3rd winding exclusively for NFB and re-calculated feedback amount, a well balance of dynamic and low distortion is realized.
• Power and sound quality co-exist created by circuit re-design and re-tuning most CR values.
• Power supply section is heavily improved and re-layout for outstanding channel separation.
• Improved version of KONDO original silver foil signal capacitors for highest reliability.

 

Design

 

To develop an integrated amplifier which has best sound quality, simple and easy to use. True music lovers can enjoy various kind of music from delicate solo to big scale orchestra.

 

• Power tubes are famous pentode EL34, which are first application in Audio Note product. In order to secure a minimum of 30W even matching with low efficiency speakers. Output impedance are 4Ω and 8Ω selectable.
• Reference to many classic push pull circuits with addition to our original new ideas, the performance of EL34 amplifier is elevated to a completely new level, combining both dynamic and delicate tonal balance.
• Fulfilling the requirements of modern specification and keep Audio Note traditional natural music performance.

 

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. Moreover, we aimed to make the entire circuit into low impedance so that 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. Output transformer is UL connection, only 3dB NFB employed to get the best balance of low distortion and good dynamic. Furthermore, Internal wirings are skillfully arranged so that shortest paths and best performance are obtained.

 

Super High Quality Parts

 

All parts were carefully chosen after massive hours of listening tests. High grade audio volume, silver foil capacitors, silver lead resistors, SSW silk silver wires, Ls-41 shield cable, Audio Note custom made output transformers and power transformer. All CR part are carefully selected and arranged.

 

Big Power supply

 

The high reserve power supply circuit is constructed with choke coils and large capacitors group. After the ripple filter stage, the decoupling capacitors are further arranged to serve left and right channels independently. In addition, we prepared 500μF/ch in the input stages of left and right channel; achieving high headroom and wide bandwidth sound possible.

 

Specifications

 

Product	EL34 Push-Pull stereo integrated amplifier
Model	PM-2 i
Rated Power	32W + 32W @1kHz, 1% THD
Frequency Response	6Hz ～ 140kHz (+0dB -3dB @ 1W)
Input / Impedance	4pairs (RCA, unbalanced) / 50kΩ
Output	4Ω, 8Ω
Noise	lower than 0.5mV
Vacuum tube	EL34 x4, 12BH7 x2, 6072 x2
Power consumption	180W
Dimension	438mm(W) 201mm(H) 409mm(D) (excluding protrusions)
Weight	26kg
*Due to the characteristic of the vacuum tubes used, it takes around 15 minutes to reach nominal sound quality and performance level.