YSA300S-Reference  Mono Block Power Amplifier

Audio Experience YSA300S-Reference is a Mono Block Power Amplifier 
It uses three matched pair of KT120 ( KT150, KT88 ) power tubes and UL working staus to provide RMS 250W adequate output for most of the Hi-End Speakers to ideal performance. Moreover, It use the high quality output transformer ( Sowter . made in United Kingdom).
Huge dynamic range, both the beautiful tone color and wonderful rhythm , ultra linear circuit of the valve tubs power amplifier designed for the SACD source in the New Century. uncanny natural flowing heart-stirring sound that matches any other ultra-Fi products on the market .



   The input/driver stage is new design, 12AU7 input stage direct coupling to 6H30 driver stage , The driver stage use AudioCap Theta coupling capacitors to three pair TUNG-SOL KT120 power tube , The power tube work at P-P UL mode to driver Sowter 3 inch Grain Oriented (M6) laminated core output transformer , The Sowter 3 inch Grain Oriented (M6) laminated core for minimal losses and distortion. 14 section interleaved primary and secondary windings to give excellent bandwidth. Two chamber bobbin ensures full capacity and resistance balance to eliminate distortion caused by transformer unbalance. Low copper resistance to minimize losses and maximize loudspeaker damping. 

The power supply with two separately HVB+ power supply for power output stage and  input driver stage.

The components ,  NFB value , tube type , circuit all select by listen test.



 ysa300s11.jpg (631442 個位元組) AudioCap Theta coupling cap.

ysa300s8.jpg (550909 個位元組) ysa300s9.jpg (375052 個位元組) Sowter 3 inch Grain Oriented (M6) laminated output transformer

ysa300s2.jpg (538617 個位元組) ysa300s3.jpg (515980 個位元組) ysa300s4.jpg (664303 個位元組) ysa300s5.jpg (677519 個位元組)    

ysa300s10.jpg (457628 個位元組)  ysa300s6.jpg (483441 個位元組) ysa300s7.jpg (507292 個位元組)


Racewong report - 膽後風情 YS AUDIO YSA300s

好耐無未試過咁興奮 ~ YS AUDIO YSA300S POWER AMP


Output and T.H.D :  
1W per channel , 1kHz total harmonic distortion typically 0.1% (0.2% at 20Hz , 0.3% at 20KHz)
250W per channel , 1kHz total harmonic distortion typically 2% (rated output)

RMS Max: 350W

Input :  RCA and XLR (balanced)

Input Impedance :  100K ohm is  RCA , 10K ohm is XLR .

Frequency Response:  

1W    20Hz ~ 100KHz ( 20Hz 0dB, 100KHZ -3dB)
250W  20Hz ~ 50kHz (20Hz -1.5dB , 50kHz -3dB)

Input Sensitivity :  1.5V / 250W

Output Impedance: 4 ohms.                                                      

Noise: Less than 1mV
Damping factor : approximately over 23

Phase Mode : Normal

Tubes Required per channel: Three Matched pair KT120 Power Output , ( 1 ) 6H30 Driver , ( 1 )12AU7 Input .

Dimension: 433mm x 460mm x 233mm (W x D x H) each

Total Weight two block: 58kg

Power Source: 110-117 or 220-240V,50/60Hz


With XLR input ( Jensen input tran ) HK$56000.

Without XLR input (Jensen input tran) HK$55000.



Room1308, 13/F,BLK C,.  
Kai Tak FTY BLDG.   
99-101 King Fuk ST,.   
San Po Kong,   KLN,.
Hong Kong
E-mail : info@ys-audio.com 
WhatsApp: 93440168   
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