FiiO E12DIY Limited Edition Version---DIY your own sound !

Discussion in 'Portable Headphone Amps' started by jamesfiio, Jul 31, 2013.
  1. NCSUZoSo
     
    Then why are they plugged into the buffer locations?
     
  2. snellemin
    Just to see what it could do, which is barely anything.
     
  3. NCSUZoSo


    I didn't even know you could do that.
     
    Can someone who has their E12 DIY out of the case do me a favor and check the resistance value of the two resistors found on the volume knob traces (backside of PCB/opposite of op-amp side) shown below:

    Also if someone really wants to help me check continuity at the two spots I showed failing on my circuit below. 

    1. The top resistors of the parallel resistors (current divider?).
    2. The bottom resistor on the volume knob traces.
     
    E12PCBExposedbottomIllustrationsAddedSm.jpg

    Also, could someone look at the reset switch/button and tell me if it easily moves in a circular pattern if pushed on from an angle with slight pressure. I am trying to make sure I didn't accidentally break the reset switch and that is causing my problem/s.

    I noticed when I was trying to use the reset with my thumb (PCB out of enclosure) that it didn't only push straight down, it moved like a basketball rimming out of the basket before pushing straight down. I do not think this is normal and it might be my needed fix...

    Be careful if you do check your reset switch, don't want you to break yours if this isn't normal. Give it very light pressure and see if it leans at all when light pressure is applied from the top and a slight angle. I believe it is supposed to be rigid and only move up and down (like any switch I have used/installed in the last 20 years).

     
     
  4. snellemin
    The two resistors by the potentiometer are between 101 and 102 ohms.
    The one by the voltage divider is 463 ohms.
     
    NCSUZoSo likes this.
  5. NCSUZoSo
     
    Thanks for the information on the resistance values so quickly! There is nothing wrong with me trying full-size resistors of equal resistance in their place right?  Should I use 1/4 or 1/2 watt? I am assuming 1/4 watt.

    However isn't that a current divider? Resistors in series would be a voltage divider while parallel resistors create a current divider.

    http://www.allaboutcircuits.com/textbook/direct-current/chpt-6/current-divider-circuits/
     
  6. snellemin
    You could use 1/8W resistors.  
     
  7. Pete7

    There are op-amps that output enough current that they can be used as buffers, such as AD797 (but not in the DIY because it's a single) or AD8397.
     
  8. NCSUZoSo
    Can you check your reset switch like I had mentioned? If not, I am sure someone will have their E12 out of the enclosure and can check for me soon.

    If anyone wants me to check values of any components or think you see something suspect in my pictures let me know! I am in contact with FiiO, but I get faster input/feedback from this forum.
     
    Here is a shot of the entire bottom of the PCB without any writing in the way:

    Full Res: https://www1.picturepush.com/photo/a/15624789/img/Audio-Related/E12-PCB-%28Plain%29-v2.jpg

    E12PCBPlainv2.jpg
     
  9. snellemin
    My switch has zero play in it.  
     
  10. NCSUZoSo

    Thank you, I think this might be the problem.
     
    I wonder how you find a switch/button such as that one?
     
  11. snellemin
    The switches can be found, I just don't have a link right now.  Or you can buy a used FIIO for parts.  There is one E12 on Ebay for 35 bucks.
     
  12. CH23
    I think it might be either the RK0971221Z05 or the RK0971221Z11 as specified on http://www.alps.com/prod/info/E/HTML/Potentiometer/RotaryPotentiometers/RK097/RK097_list.html


    MIGHT BE. no guarantees given.
     
  13. odessamarin
    @NCSUZoSo
     
    I would like to try V5-OPA-D or V5i-D in my set.. which one you could suggest to get. What is the main difference you find comparing them in E12?
    thx
     
  14. snellemin
    Got me a interesting opamp.  Uses two dual opamps, but one is used as a buffer to the second one.  Sounds pretty good.
     
    WP_20170203_11_30_06_Pro.jpg
    WP_20170203_09_11_29_Pro.jpg
     
  15. audioxxx
    I had the same biasing issue soon after receiving my fiio e12diy, where the amp would crackle and pop no matter what opamp went in.

    And after searching the board for hours for the fault, I couldn't find it, so off it went on its long trip back to Fiio for repairs.
    The amp was returned several weeks later repaired and working perfectly, and with a new battery. I had to pay a small fee, however it was well worth it. Unfortunately after requesting what the fault was, I couldn't get a clear response, as to the exact issue.
    (I was told it was a dry joint near the headphone jack)
    I was also told I didn't cause the issue.
    I'm still really enjoying this amp especially with the opa627au opamp installed, this amp sounds very clean.

    20170204_134644.jpg
     

Share This Page