YSA-300B  7W+7W Integrated Stereo Valve Tube Amplifier  Version: 1.5

Retired Product

Audio Experience YSA300B  version 1.5 is a 7W + 7W Integrated Stereo Valve Tube Power Amplifier.
   The power amplifier use one Shuguang 300B power tubes work at SET Single Ended Triode configuration status to provide Class A 7W adequate output . Moreover, It use the high quality output transformer ( Hasimoto . made in Japan).

   The version 1.5 with high / low gain selector,  high gain for Integrated amplifier model, low gain for power amplifier model.

   The line preamp stage use 6SJ7 tube , The driver stage use 6SN7 to driver 300B power tube . The 300B tube work at SET Single Ended Triode mode to driver Hasimoto HC-203U high quality output transformer , The Hasimoto HC-203U EI output transformer has very low Insertion Loss 0.6dB only.  ( Many SET tube power amplifier in Hi-End audio market , Their have the output transformers is over 2dB 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. 

    This power amplifier case structure and parts arrangement are perfect, the signal path is directly and shortly connected. Great heat dissipation, an anti-shock and anti-RF function to guarantee it works at a very stable status. For sure, this machine is produced by point-to-point methodology. 



ysa300bintg1.jpg (533607 個位元組) ysa300bintg2.jpg (595328 個位元組) ysa300bintg4.jpg (555466 個位元組)

ysa300bintg5.jpg (472724 個位元組) ysa300bintg6.jpg (516861 個位元組) ysa300bintg10.jpg (566105 個位元組) ysa300bintg11.jpg (772517 個位元組) High / low gain selector.

ysa300bintg8.jpg (486859 個位元組) hc203u.jpg (699179 個位元組) Hashimoto HC-203U output transformer.



Output and T.H.D :  

High gain:
1W per channel , 1kHz total harmonic distortion typically 0.4% 
7W per channel , 1kHz total harmonic distortion typically 5%  (rated output)

Low gain:
1W per channel , 1kHz total harmonic distortion typically 0.2% 
7W per channel , 1kHz total harmonic distortion typically 5%  (rated output)

Input :  4 pair RCA 

Volume, Input selector , input gain , main high/low gain selector,  Power On/Of

Input Impedance : RCA is 100K ohm

Frequency Response:

High gain:
Test at 1W  20Hz ~ 23kHz  (20Hz  0dB, 20kHz -2.3dB, 23KHz -3dB)
Test at 7W  20Hz ~ 23kHz  (20Hz -1dB, 20kHz -2.3dB, 23KHz -3dB)

Low gain:
Test at 1W  20Hz ~ 53kHz  (20Hz -0dB, 20kHz -0dB, 53KHz -3dB)
Test at 7W  20Hz ~ 53kHz  (20Hz -1dB, 20kHz -0dB, 53KHz -3dB)

Input Sensitivity :  volume at MAX ,  
High gain: 0.125V / 7W (rated output)   36dB gain (test at 8ohm)
Low gain: 0.25V / 7W (rated output)   30dB gain (test at 8ohm)

Output impedance : 4 ohm , 8ohm , 16ohm

Noise: Less than 1mV
Phase Mode : Normal

Construction: Copper and High quality aluminum

Tubes Required: 6SJ7WA x2 , 6SN7 x2 , 300B x 2,  5AR4 x 1

Dimension: 400mm x 300mm x 210mm (W x D x H)

Total Weight: 16kg

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

Retired Product

Actual Price: HK$20,380


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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