Theme Settings

Mode Layout
Theme color
Choose your colors
Background Color:


XiangSheng 728A Tube PreAmp Tons Adjustable HIFI EXQUIS Wada Shigeho Cuircuit Pre-amplifier

 Be fan

Be fan of our Facebook page and get $5.00 discount!

 Be fan

If you are not logged in to Facebook, please first log in and then refresh this page before clicking the Like button. Otherwise, you will not get your voucher.

Customer ratings and reviews

Nobody has posted a review yet

New product





  • With Bluetooth
  • Without Bluetooth

ngsheng manufacture have 3  different 728A preamplifier model,

  1. 728A without Ton adjustement

  2. 728A with Ton adjustement without remote(we sell this model in this page)

  3. 728A with Ton adjustement with remote with balanced input and output

This page we sell  the 2nd model : 728A with Ton adjustement without remote

No Bluetooth: option is preamplifier comes WITHOUT Bleutooth module:


Bluetooth: option is with Bleutooth 5.1 module:



Wonderful  stereo  Pre-Amplifier,  built  with the  best  parts  available,(HIFI EXQUIS)
The  pre-amplifier  improved  based on  famous  Wada  Shigeho's  Style  Electric  circuit, which  was  Introduced  by Wada  Shigeho  in the  early  1960s  and gave  an  excellent  performance.
Regarding  the Wada  Shigeho's  Style  Electric  circuit, it not  only  still  keep the  good  features  of  Marantz7,meanwhile  it have  superrior  features  in  Dynamic, High/Low  Frequency  Response,  Resolution  and  Signal  to Noise  Ratio as  compared  to  Marantz7.But  apart  from  above  features,  it’s  also not  inferior  to  Marantz7  in Sound  stage  and airy  feeling. Adopt  4 PCS  paper in  oil  capacitors  and  German  WIMA  capacitors  for  coupling  effect, make  the  sound  warm and  delicate.(HIFI EXQUIS)

Product characteristics :
The reference of
Wada  Shigeho's circuit toimprove lines and adjust according to the different uses of the bile duct peripheral component parameters to maximize the strengths of the bile duct , so that the machine can no matter what the outstanding performance of the bile duct . Japanese and Shigeru launched in the early 1960s, the performance is excellent. It maintained a Marantz7 mellow and full of musical taste characteristics, but regardless dynamic , transient, high frequency response , power analysis , signal to noise ratio than Marantz7 good , and in the sound field , transparent flu and Marantz7 enough to keep pace .(HIFI EXQUIS)


  • Size : 430 × 90 × 290mm

  • Input impedance : 100K;

  • Output impedance : 600 ohms

  • Output max volatage: 15v

  • SNR : 90dB;(HIFI EXQUIS)

  • Frequency Response : 10Hz - 30KHz;

  • Distortion : ≤ 1%.

  • Input Power :    AC100V-AC240V available 60Hz/50Hz

  • Output Tube : 2x ECC81(12ax7), 2xECC82(12au7)  ,  6Z4 rectifier×2,

  • Input Sensitivity :    400m

  • Humidity :    35%—80%(HIFI EXQUIS)

  • TMD :    less than 0.01%

  • Input Jack :    4 groups

  • Output Jack :    2 groups(same voltage), you can connect double same amplifiers

  • Net weight : 8.5kg,

  • Package size weight : 11.8kg

  • Colors:BlackorSilverfront panel to choose

The export-oriented unit 728 in the third generation on the basis of preamp after many improvements made , compared with the original machine , elegant and dignified appearance , taste extraordinary.
In addition to retaining all of its advantages, it also increases the following advantages :

  • Bluetooth 5.1 (option): support APTX-HD and LDAC, with CS4398 decoder chip

  • The circuit board designed interior layout is more reasonable , clean and beautiful .

  • The front panel with silver plating 6mm thick aluminum wire drawing process panel , blue power indicator tube , and adds a unique large window display tubes , with warm red-orange background , higher grade quality .

  • Advanced sandblasting paint process sheet steel enclosure , high light metal knobs, a large cellular machine feet.

  • 4 stereo input signal switch , rotary switch control using conventional sealed relays senior converted signal , avoiding the switching noise , long life.

  • using a relay signal output delay , to be enlarged after the tube into the steady state relay output signal , avoiding the unpleasant noise generated in the tube preheating process .

  • The output signal provides two output sets, both you can connect two power amp together, you can also connect two integrated Amplifier do tone regulator uses.

  • Input and output interfaces that are used in a gold-plated RCA seat

  • Increase the grid filter purification circuit , you can filter the grid and DC components of clutter .

  • Taiwan good quality potentiometer volume control.

  • Antique oil capacitors and German WIMA red MKP polypropylene capacitive coupling.

  • Using the best quality in the transformer power supply R-type bovine ( Square transformers and toroidal transformers leakage magnetic flux leakage is large, and therefore have a greater radiation frequency noise, and small R-type is very small ) , using high-pressure tube rectifier in parallel , two large reservoirs and high-quality inductors filtering.

  • With treble, bass, treble and bass straight ( bass and treble adjustment automatically shield ) , volume, balance adjustment.