Hybrid Vacuum Tube Headphones Amplifier (Part 4) Upgrade Using Foxconn Mini Jack

This hybrid vacuum tube headphones amplifier has comes in 3 part. I don't have any planning to make an additional post about this but because it sound so good and beyond my expectation, so why not to make some update posting.

For pass few days, I have listen from this little vacuum tube amplifier and it is a new listening experience for me. In the initial built, I am using cheap 3.5mm socket connector. This is very common to use cheap components for the first trial and upgrade it latter. But with this outstanding result, I can spending more for the better components.

So in this post I will return this amplifier to my working desk and make an upgrade on the 3.5mm socket is now using Foxconn.

The connector I use before is a junk. It cannot make a good contact with the jack and it loose out easily. So I purchase this new connector. The brand is Foxconn and you probably familiar with the name as well. This connector is very well made, high quality and of course heavy duty for this application.

The problem right now is this Foxconn socket is having tiny leads. I should make the extension leads on them for connecting to the PCB.

The next steps is make a fitment on the PCB and the tin casing.

Luckily I don't need to make an adjustment on the tin holes since the diameter are all the same as previous socket.

I also make a PCB holder by using a wire soldered to the chassis tin, so the PCB will stay on it place.

The rest is put all together again, such as DC socket, LM317 and heat-sink, the volume knob and the vacuum tube itself.

Just like any desktop amplifier, I attach rubber feet on the bottom of it.

With all of 3 part of this hybrid vacuum tube amplifier built, here are the bill of materials I spent.

1. Universal board 6x8cm        1 pcs    each $0,50       $0,50

2. Dale RN55 resistors             7 pcs    each $0,34        $2,41

3. Rubycon ZLH capacitors     6 pcs    each $0,21        $1,24

4. Alps green potentiometer     1 pcs    each $5,17        $5,17

5. Brouns multiturn VR            1 pcs    each $0,83        $0,83

6. Wima MKS-2 100n              2 pcs    each $0,49        $0,97

7. Nextron IC socket                1 pcs    each $0,34        $0,34

8. TI OP275 dual op-amp        1 pcs    each $2,41        $2,41

9. Foxconn 3.5mm socket        2 pcs    each $1,72        $3,45

10. Tube socket 9 pin               1 pcs    each $1,89        $1,89

11. NOS 6N23P              1 pcs    each $8,62        $8,62

12. DC socket                          1 pcs    each $0,14        $0,14

13. TI LM317T                        1 pcs    each $0,83        $0,83

14. TO-220 heat-sink               1 pcs    each $0,10        $0,10

15. M&S candy tin                   1 pcs    each $3,45        $3,45 bonus candy

16. Teflon jacket cables            1 meter                         $0,83

17. 3M rubber feet                    1 pack  each $1,79       $1,79

18. Volume knob                       1 pcs    each $0,20       $0,20

Total material cost, excluding working tools US$35,17 quite cheap isn't it.

So at the end, it is a great pocket size vacuum tube amplifier project. It sound really good and listening music from it while see the vacuum tube glowing is the best experience for every audiophile.

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