Sansui AU-555A Rebuild Cap Coupled Goodness

Discussion in 'Exclusively Sansui' started by patfont, Mar 19, 2015.

  1. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    It is listed as a choke coil in the SM. There are 2 on the board.
     
    Last edited: Apr 1, 2015
  2. c.coyle

    c.coyle Fighting the Dunning-Kruger Effect Subscriber

    Messages:
    2,593
    Location:
    40.333468 -76.423711
    What is the advantage over a polarized audio grade electrolytic?
     
  3. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    Here are the caps removed from the board, one rolled out under the bench which I found later.

    [​IMG]


    Here is the finished board, I used a 4.7uf Wima film for the output caps in place of the 10uf e-cap for an upgrade.
    This board got: 1 pr. Wima MKS2, 1pr. Nichicon KL, 1pr. Nichicon FG and the rest Elna Silmic II.

    [​IMG]


    [​IMG]



    Here she is all done and sounding smooth and punchy! Will let it play awhile and then bring up to the main system for a listen.



    [​IMG]
     
    Last edited: Apr 1, 2015
    backinthelou likes this.
  4. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    .......see post #29:D



     
  5. c.coyle

    c.coyle Fighting the Dunning-Kruger Effect Subscriber

    Messages:
    2,593
    Location:
    40.333468 -76.423711
    Whoops. Missed it. I think you're gonna love this amp.
     
  6. slimecity

    slimecity Super Member

    Messages:
    1,344
    Location:
    New Zealand
    These are great little amps once restored. Tons of bottom end. LOVE the Silmics - they revolutionise the sound.
     
  7. Alienz

    Alienz Super Member

    Messages:
    1,249
    Location:
    The Netherlands
    Great job again Pat :)

    Only question I have: would using a Wima film cap instead of a COG also make an improvement or does it have to be ceramic?
     
  8. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    Yes you could use a Wima FKP they are available from Mouser in both values needed. The problem is with the fit. The phono board would be a tight squeeze, looks like the amp board would be fine. You also have the option of mounting on the back of the board if you choose.






     
  9. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    Yes I am lovin' the Sansui sound! I just got a 505 here and am going to see what she can do with some all out upgrades. Will post a thread when I get started.




     
  10. Alienz

    Alienz Super Member

    Messages:
    1,249
    Location:
    The Netherlands
    Thanks Pat :)

    Did you keep the 2SC871's in there or replaced them as well?
     
  11. stereofun

    stereofun AK Subscriber Subscriber

    Messages:
    1,052
    Location:
    Tucson, AZ
    ...and don't forget the 777 series. I have the "a" version along with two 555a and a 505. The 505 has impressive low end and can project a sound much bigger than its 23 watts calls for, whereas the 555a has better definition higher up the register. I might even pick the 505 if I really had to choose between the two.

    But the 777a is a true class act and the king of the cap couplers if you ask me. I'd even pick it over a 999 a 517 and an Eight, but not an Eight deluxe.
     
    smurfer77 likes this.
  12. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    The 2SC871's are still on board. There does not seem to be a direct drop in for them with the same gain. I have a decent list of bad boy transistors and the 2SC871 is not on it.






     
  13. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    What I really love about the 555A and the 505 is that they sound so amazing even at very low volumes. And compared with a Marantz 1060 the 555A is able to achieve higher volumes without breaking up while playing one of my torture test songs Perculator by Slice and Case.







     
    smurfer77 likes this.
  14. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    I have a 505 here now and I think I will try the C0G and Wima FKP on the amp board, and see if I have a preference.





     
  15. Alienz

    Alienz Super Member

    Messages:
    1,249
    Location:
    The Netherlands
    :thmbsp:

    My local tech store doesnt stock FKP's this small or COG's so I have to wait for my next big order.
     
  16. WarriorAnt

    WarriorAnt New Member

    Messages:
    35
    Location:
    The Sonoran Desert
    Did you ever get to compare a COG and Wima FKP on the amp board of the 505?
     
  17. catama

    catama AK Subscriber Subscriber

    Messages:
    399
    Location:
    Northern California
    I am the very fortunate new owner of this beauty. Thank you, thank you, Pat! You are a genius!

    When I hooked it up today, I was stunned. To give you an idea of how good this unit sounds, it rivals my McIntosh MX110/MC2505 set up using the same sources. The sound is crystal clear, detailed, distortion free and very warm. Very much like a tube set up. The mids are wonderfully executed and the bass is tight, focused and vibrant. You can feel the vibrations on a string bass! The highs are lush, expansive and sweet. Pat was right. This unit is a sleeper. Count me a believer. This is my first Sansui. It may not be my last. I may sell my Mac gear!

    In case you want to know, the speakers are Reference 3A mm de capos, the TT is a Thorens TD125MKII, the tuner is a Jolida 402 and the tape deck is a Pioneer RT707. I am in heaven!
     
    smurfer77 likes this.
  18. stereofun

    stereofun AK Subscriber Subscriber

    Messages:
    1,052
    Location:
    Tucson, AZ
    Dang it - don't spread the word too much. The cap coupled Sansui's are world class once restored and modded. Trust me, a restored 777a will best the 555a.
     
    BLAH BLAH and slimecity like this.
  19. patfont

    patfont AK Subscriber Subscriber

    Messages:
    3,017
    Location:
    South Jersey
    Thanks Andy!

    I am so glad you love it, it just seems to tick all the right boxes. And yes the upper bass has real punch and drive. Def reminds me of tube gear as you can really hear/feel the visceral impact of a plucked string in the chest.










     
  20. c.coyle

    c.coyle Fighting the Dunning-Kruger Effect Subscriber

    Messages:
    2,593
    Location:
    40.333468 -76.423711
    Couldn't agree more. I've been enjoying mine for about 8 months. Your description is spot on.

    My fix-up of a 1969 AU-777A isn't going as fast as I'd like, but there are early signs that it might even be better.

    These are just heavenly amps.
     

Share This Page