YSA150S-Reference Version 1.5  150W + 150W Stereo Valve Tube Power Amplifier

Audio Experience YSA150S-Reference Version 1.5 is a 150W + 150W Stereo Valve Tube Power Amplifier.
Version 1.5 is last version
Old version see there

It uses two matched pair of KT150 power tubes and UL working status to provide RMS 150W adequate output for most of the Hi-End Speakers to ideal performance. Moreover, It use the high quality output transformer ( Hasimoto . made in Japan).
Dual mono power supply design ( It is same one pair mono block build in at one chassis )
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 MultiCap RTX coupling capacitors to TUNG-SOL KT150 power tube , The power tube work at P-P UL mode to driver Hasimoto special grade CUT CORE orient high B" output transformer , The output transformer has very low Insertion Loss 0.13dB only.  ( Many tube power amplifier in Hi-End audio market , Their have the output transformers is over 1dB Insertion Loss . only about 10% very high price tube amplifier use under 1dB Insertion Loss of output transformer ) . The output transformer has low insertion loss is very important , the best of the best is 0 dB Insertion Loss , The output transformers for High End tube amplifier need under 1dB  Insertion Loss . The Insertion Loss over 1.5dB output transformer will lost many low level music.

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




ysa150sv2l.jpg (394321 個位元組) Dual mono power supply ( this is equal one pair mono block build-in one chassis )


ysa150sv2k.jpg (347860 個位元組) ysa150sv2m.jpg (374728 個位元組)  Power supply use Mundorf power caps

ysa150sv2j.jpg (397365 個位元組) MultiCap RTX coupling caps

realxlout.jpg (707814 個位元組) Hasimoto special grade CUT CORE orient high B output transformer.

ysa150sv2b.jpg (388524 個位元組) ysa150sv2c.jpg (523865 個位元組) ysa150sv2d.jpg (445416 個位元組) ysa150sv2e.jpg (407996 個位元組) ysa150sv2f.jpg (484111 個位元組) ysa150sv2g.jpg (442106 個位元組) ysa150sv2h.jpg (504714 個位元組) ysa150sv2i.jpg (413648 個位元組)   




Power On/Of, Input RCA/XLR Selector 

Output and T.H.D :  
1W per channel , 1kHz total harmonic distortion typically 0.09% (0.15% at 20Hz , 0.2% at 20KHz)
150W per channel , 1kHz total harmonic distortion typically 1.5%

Input :  RCA and XLR (balanced)

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

Frequency Response:  

1W    20Hz ~ 100KHz ( 20Hz 0dB, 100KHZ 0dB)
150W  20Hz ~ 100kHz (20Hz -0.4dB , 100kHz -3dB)

Input Sensitivity :  1.6V / 150W       25.5dB Gain ( Test at 8 ohm )

Output Taps: 16 ohm ,8 ohms, 4 ohms.                                                      

Noise: Less than 0.5mV
Damping factor : approximately over 23

Phase Mode : Normal

Tubes Required per channel: Two  Matched pair KT150 Power Output , ( 1 ) 6H30 Driver , ( 1 )12AU7 Input .

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

Total Weight: 32kg

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

Actual Price: 

With XLR input ( Jensen input tran ) HK$42300.

Without XLR input (Jensen input tran) HK$39800.


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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