Introduction

Products History 
Mr Chui Yat Sang 

Since there is no photo record on some products and before 1988 , 
the introduction below is just part of the products made by Mr Chui Yat Sang.

6L6GC Power Amp

Date of production : 1989
Introduction : 6L6GC 13W Push-Pull (Triod) Mono Block Power Amplifier
Recent Situation: Repairing

lee300b1.jpg (77260 個位元組)

Date of production : 1996
Introduction : 300B Sing-Ended Mono Block Power Amplifier
Tube complement :  one 6SN7GTB input and driver , one 300B output , one 5R4 rectifier. 
Transformer complement : Hi-Pro Force power , Tango X-5S output , 
                                           Shuguang 3H 700mA choke.    
Serving Mr Lee in Australid

s9ou1s.jpg (156948 個位元組)

Date of production : 1994 ~ 1995
Introduction : EL34 x4 120W Ultra- Linear Push-Pull Power Amplifier
Tube complement : one EF86 input , one A2900 driver , two matched EL34 pairs (output)
Transformer complement : Shuguang power ,  Shuguang 3H 700mA choke
                                           Tango X-3.5P output.
one pair in Japan , another pair in Hong Kong (Mr Chan's home)

9.jpg (110197 個位元組)

Date of production : 1995
Introduction : 300B Sing-Ended stereo Power Amplifier
Tube complement :  one 6SN7GTB input and driver , one 300B output , one 5R4 rectifier. 
Transformer complement : Hi-Pro Force power , Tango X-5S output , 
                                           Shuguang 3H 700mA choke.    
Serving Mr Tam in Hong Kong

we300b-se.jpg (30792 個位元組)

Date of production : 1993
Introduction : 300B Sing-Ended stereo Power Amplifier
Tube complement :  one 6SN7GTB input and driver , one 300B output , one 5U4G rectifier. 
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , Hi-Pro Force input
                                           Hi-Pro Force 10H 250mA choke.    
Sold in1993

ysa-100b.JPG (73903 個位元組)

Date of production : 1997
Introduction : KT-90 x4 120W Ultra- Linear Push-Pull Power Amplifier
Tube complement : one EF86 input , one E182CC driver , two matched KT90 pairs (output)
                               one 6BM8 regulator.
Transformer complement : Shuguang power ,  Shuguang 3H 700mA choke
                                          Audio Note output.
For reference

211-20w.jpg (16944 個位元組)

Date of production : 1989
Introduction : 211 Sing-Ended stereo Power Amplifier
Tube complement :  one EF86 input , one 6FQ7 driver , one 211 output , one 5AR4 rectifier.
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Hi-Pro Force 10H 350mA choke.    
Lay up (treasure) in our workshop

6L6CG-30w.JPG (16857 個位元組)

Date of production: 1988
Introduction : 6L6GC 20W Push-Pull stereo Power Amplifier
Tube complement : one 12AU7 input , one 12AX7 driver , 
                                one matched 6L6GC pairs (output)
Lay up (treasure) in our workshop

Ap.JPG (14514 個位元組)

Date of production : 1988
Introduction : 6N1 line amplifier
don't know

6c33c.jpg (75197 個位元組)

Date of production : 1998
Introduction : 6C33C-B OCL 120W external power supply Mono Block Power Amplifier 
                      (Atma-Sphere chassis)
Tube complement : one 12AX7 input , one 5963 driver , 
                               two matched 6C33C-B pairs(output).
Transformer complement : one 3000W toroidal power , one 300w toroidal power.
                                          two 0.1H 4A choke
Serving Mr To in Hong Kong

6C33C400W.jpg (147354 個位元組)

Date of production : 1995
Introduction : 6C33C-B OCL 400W Mono Block Power Amplifier
Tube complement : one 12AX7 input , one 5963 driver , 
                               Four matched 6C33C-B pairs(output).
Transformer complement : one 3000W toroidal power , one 1000w toroidal power.
                                          four 0.1H 4A choke
Serving Mr Chung in canada

6550-20w.JPG (22030 個位元組)

Date of production : 1994
Introduction : 6550A 25W Push-Pull(Triod) stereo Power Amplifier
Tube complement : one 6DJ8 input , one 6SN7GTB driver , one 6BQ5 regulator.
                                one matched 6550A pairs (output)
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Hi-Pro Force 5H 250mA choke.    
don't know

2A3-30wpp.JPG (29872 個位元組)

Date of production : 1995
Introduction: 2A3 x4 Push-Pull Mono Block 35W Power Amplifier 
Tube complement :  one 6SJ7 input , one 6K6 driver , two matched 2A3 pairs (output) 
Transformer complement :  Hi-Pro Force output , Hi-Pro Force input
                                           Hi-Pro Force 10H 350mA choke.    
Serving Mr Young in Hong Kong

6BQ5-30wpp.JPG (15817 個位元組)

Date of production : 1993 ~ 1994
Introduction: 6BQ5 x6 Push-Pull stereo 35W Amplifier 
Tube complement :  one 12AT7  input, one 12AT7 driver , 
                               
three matched 6BQ5  pairs (output)
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Hi-Pro Force 5H 400mA choke.    
Has produced a lot

2A3-15wpp.JPG (24246 個位元組)

Date of production : 1993 ~ 1995
Introduction: 2A3 Push-Pull stereo 15W Power Amplifie
Tube complement :  one 6SJ7 input , one 6K6 driver ,
one matched 2A3 pairs (output) 
Transformer complement :  Hi-Pro Force output , Hi-Pro Force input
                                           Hi-Pro Force 15H 250mA choke.    
has produced about 20

6V6pp.JPG (24058 個位元組)

Date of production : 1989 ~ 1995年
Introduction : 6V6 10W  Push-Pull stereo Power Amplifier
Tube complement : one 6DJ8 input , one 6SN7GTB driver , one 6BQ5 regulator.
                                one matched 6V6 pairs (output)
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Hi-Pro Force 5H 250mA choke.    
has produced about 20

211se.JPG (14636 個位元組)

Date of production :  1994 ~ 1996
Introduction : 211 25W Sing-Ended stereo Power Amplifier
Tube complement :  one EF86 input , one 6FQ7 driver , one 211 output , one 5AR4 rectifier.
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Hi-Pro Force 15H 350mA choke.    
Lay up (treasure) in our workshop

811Ase.JPG (24861 個位元組)

Date of production :  1994 ~ 1996
Introduction : 811A  16W Sing-Ended stereo Power Amplifier
Tube complement :  one 6SL7 input , one 6L6G driver , one 811A output .
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , Hi-Pro Force input
                                           Hi-Pro Force 15H 350mA choke.    
has produced a lot , two of them lay up in our workshop

6L6gc50w.JPG (19845 個位元組)

Date of production :  1995
ntroduction : 5881 50W Push-Pull stereo Power Amplifier
Tube complement : one 6SL7 input and driver , one 5AR4 rectifier.
                                one matched 5331 pairs (output)
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Hi-Pro Force 5H 500mA choke.    
Serving Mr Yip in Hong Kong

EL34-120w.JPG (16624 個位元組)

Date of production :  1990
Introduction : EL34 x6 120W Ultra- Linear Push-Pull external power supply Power Amplifier
Tube complement : one 6N2 input , one 6F2 driver , three matched EL34 pairs (output)
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Two Hi-Pro Force 5H 500mA choke.    
has produced a lot , one of them lay up in our workshop

300B13Wse.JPG (28361 個位元組)

Date of production : 1993 ~ 1996
Introduction : 300B Sing-Ended Mono Block Power Amplifier
Tube complement :  one CV181 input , one 6L6G  driver , one 300B output 
                                 
one 12AX7 regulator , one 6080 regulator.
Transformer complement : Hi-Pro Force power , Hi-Pro Force output , 
                                           Two Hi-Pro Force 10H 250mA choke.       
has produced about 20 

EL34-90Wpp.JPG (10654 個位元組)

Date of production : 1990
Introduction : EL34 x4 90W Ultra- Linear Push-Pull Power Amplifier
Tube complement : one EF86 input , one 12AU7 driver , two matched EL34 pairs (output)  
Lay up (treasure) in our workshop

Ms.jpg (35232 個位元組)

Date of production : 1996
Introduction: 300B  Push-Pull Mono Block 45W Power Amplifier 
Tube complement :  one 12AX7 input , one 5963 driver , one matched 300B pairs (output)
                                 
one 12AX7 regulator , one 6080 regulator.
Transformer complement :   Shuguang power ,  Shuguang  choke
                                           Tango X-3.5P output.

Introduction: YS-Audio YSP-200 external power supply Preamplifier
Tube complement :  two 12AX7 and two 6V6 Line stage .
                                one 6SJ7
regulator , two 5881 regulator , one EF80  regulator ,
                                one 6BQ5 regulator, for  power supply.

Serving in Malaysia

Date of production : 9 / 2000
Introduction: Tubes Line preamplifier with Input and Output transformer .
Tube complement :  Two Western Electric 396A P-P Line stage , One 83 rectifier
Transformer complement : UTC A26 line output , UTC A11 line input .
specially match SE power amplifier.
 

n.jpg (160434 個位元組)

Date of production : 10 / 2000
Introduction: Tubes balance Line preamplifier with Input and Output transformer .
Tube complement :  Two Western Electric 396A balance Line stage , 
Two Sylvania 6BH8 regulator for HV B+ power supply every channel
Transformer complement :  Tango NP-8 line output , Sowter 9062E line input .
AA Grade Hi-End full balance line preamplifer .
Serving Mr Chan in Hong Kong

a26pm.JPG (61492 個位元組)

Date of production : 11 / 2000
IntroductionTubes Line preamplifier with Input and Output transformer .
Tube complement :  Two Western Electric 396A P-P Line stage , One 83 rectifier
Transformer complement : UTC A26 line output , UTC A20 line input .
specially match SE power amplifier.
Serving Mr Buhl in Germany

n2.jpg (122813 個位元組)

Date of production : 12 / 2000
Introduction: Tubes full balance external power supply Line preamplifier with Input and Output transformer .
Tube complement :  Two Western Electric 396A balance Line stage , 
Two Sylvania 6BH8 regulator for HV B+ power supply every channel
Transformer complement :  Tango NP-8 line output , Sowter 9062E line input .
AA Grade Hi-End full balance line preamplifer .
Serving Mr Chan in Hong Kong

a26mk3.jpg (71024 個位元組)

Date of production : 1 / 2001
Introduction: Tubes Line preamplifier with Input and Output transformer .
Tube complement :  Two Western Electric 396A P-P Line stage , Two 6U8A regulator for HV B+ power supply every channel
Transformer complement : UTC A26 line output , UTC A11 line input .
Specially match SE power amplifier.
 

superkt88.jpg (235425 個位元組)

Date of production : 2 / 2001
Introduction: Ultimate Grade ,  full balance KT88 power amplifier.
Output power : RMS 100W / 30Hz sine wave, Max 175W / 30Hz .
Tube complement : 
One Sovter 6AS7  for 600V/350mA B+ regulator power supply
One ECG 6SJ7 for 600V/350mA B+ regulator power supply , 
One Sovter 6BM8 for 300V/40mA B+ regulator power supply , 
Two Telefunken 12AT7 balance input 
One Mullard ECC82 driver
Two G.E.C. KT88  AB1 P-P power output
Transformer complement :  
Tango X-5P output. 3 pcs Tango choke , Hi-Pro Force power .
Serving Mr Chan in Hong Kong

u300b1.jpg (274295 個位元組)

Date of production : 9/2001
Introduction: Ultimate Grade , 300B or VV52B SE power amplifier.
Output Power : 
Use VV52B RMS 17W / 30Hz sine wave , Max 34W / 30Hz .
Use 300B RMS 10W / 30Hz sine wave , Max 32W / 30Hz.
  
Tube complement : 
One Western Electric 420A for 500V / 150mA B+ regulator power supply
One Western Electric 396A for 500V / 150mA B+ regulator power supply.
One Western Electric 417A input
One Western Electric 350B driver
One Western Electric 300B power or VV52B power.
Transformer complement :  
Tango XE-60-3.5S , Lundahl  interstage for 350B driver power tube , 
Hi-Pro Force power , GE choke.

More.......

Serving Mr To in Hong Kong

uad1pp1.jpg (237376 個位元組)

Date of production : 10/2001
Introduction: Ultimate Grade , AD1 P-P power amplifier.
Output Power : 
RMS 10W / 30Hz sine wave , Max 15W / 30Hz.

Tube complement:
One Telefunken RGN4004 rectifier
One Telefunken AC2 input
Two Telefunken RE074 driver
Two Telefunken AD1 power .
Transformer complement :  
Tango XE-60-8P , UTC A20 input , Western Electric choke ,
Fluke choke , Paeco power .

More........

Serving Mr To in Hong Kong

EL156_200W.jpg (213402 個位元組)

Date of production : 11/2001
Introduction: Reference Grade , EL156 x4 P-P  power amplifier.
Output Power : 
RMS 112.5W / 30Hz sine wave , Max 220W / 30Hz.

Tube complement:
One  Western Electric 417A input
One Telefunken ECC82 driver
Four Telefunken EL156 power 
Transformer complement :  
LUNDAHLL Sweden 250W Output , LUNDAHLL Sweden Input , 
LUNDAHLL Sweden Power x 2, Shuguang  choke.

Serving Mr Wong in Hong Kong

new_396ap.jpg (98602 個位元組)

Date of production : 4/2002
Introduction: Reference Grade Tubes full balance external power supply Line preamplifier with Input and Output transformer .
The preamplifier working by 396A P-P mode with output transformer.

Tube complement :  Two Western Electric 396A balance Line stage , 
Two Sylvania 6BH8 regulator for HV B+ power supply every channel

Transformer complement :  Western Electric line output , Sowter line input . 
Serving for Mr Kim in South Korea

U_one.jpg (64150 個位元組)

u_one2.jpg (186269 個位元組)

Date of production : 6/2002
Introduction: Ultimate Grade Tube Line Preamplifier.
with Balance or RCA Input and Balance or RCA Output , Remote.

The preamplifier working by 396A SE mode with output transformer.
with twin Crystal SC3310 digital volume control.
Twin solid state regulator for HV B+ power supply with tube current control 
every channel.

Tube complement :  
Western Electric 417A input.
Western Electric 396A output.
Western Electric 412A current control.

Transformer complement :  
FLUKE power , HP choke , Tango Line output , LUNDAHLL Sweden input.

Serving for Mr Chan in Hong Kong.

YS-Audio
Room1308, 13/F,BLK C,.  
Kai Tak FTY BLDG.   
99-101 King Fuk ST,.   
San Po Kong,   KLN,.
Hong Kong
Tel:(852)93440168    
E-mail : info@ys-audio.com