Posted on Sunday, 6th December 2009 by Jimmy Auw

I will not use “Ultimate” or “Premium” project since no one knows (even me) the result of this Gainclone project. I would say… “Ridiculous Gainclone”. Is that OK? ;) To be honest, this more likely a mini battleship (A-Wing?) on the StarWars movie than an amplifier.

A brief view of it, from the top. Powered with Mundorf Supreme Silver/Gold/Oil as input coupling capacitor (2.2 uF), Vintage NOS SCR 22 uF as feedback capacitor, and Black Gate F Series as power capacitor, bypassed with K40Y Russian oil capacitor. Isn’t that “ridiculous”?

0_aufmaker

Keep reading, I will show some things I have done today to assembly my Gainclone.

First, I need to clean the leads of the LM1875. You can use scissor to clean the leads to remove any dirt (to make a perfect contact? Yeah right!).

1_notsoldered

Then, add some WBT Solder on the leads. Why? This will create better signal path (because WBT Solder contains silver inside). Oh well, you can pick any solder which you prefer most. Mundorf M-Solder with Gold also quite recommended. But since this LM1875 tends to have “warmer” sound, so adding some WBT here should be perfect.

2_wbt

Make sure everything is OK? I need to check the “health” status of my capacitors. Especially the NOS one. My Sanwa analog multitester is my best friend for this purpose. Perfect and accurate.

4_sanwa

Also need to check for the capacitance. Less then 5% is accepted for me.

3_capacitancemeter

The feedback capacitors are mounted. Umm… what a size!

5_feedbackcaps

Cannon mounted! I mean, the 2.2 uF Mundorf Silver/Gold/Oil ;)

6_all

Another shoot from other side. Those tiny LM1875 are mounted directly to the bottom heatsink. Should be enough to deliver about 20 Watts RMS.

7_side

Shoot from the back side. I use “cheap” Shark RCA connector. Will upgrade to Cardas Rhodium later.

8_side2

That’s it! How does it sound?

Ha~~~ I haven’t tested it! It was too late at that time. Too tired, too lazy, and don’t have enough stamina to held a listening session (and I also haven’t finalized my power supply design anyway). So just wait…


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Posted in DIY Audio | Comments (28)

28 Responses to ““Ridiculous” Gainclone Project”

  1. Gaëtan Says:
    December 7th, 2009 at 05:02

    Hi Jimmy,
    Thank you so much for sharing your passion as you do it so well. Your website is full inspiration for me and you explain thing in the right manner. Would you mind telling me the chosen value of you power supply decoupling bypass capacitor(K40Y Russian) that you will start with. Also are you using an output coupling capacitor as shown in the typical application datasheet named C5?
    I was just curious as I’m currently playing around with tda2030 as first project but may want something more serious for later and I’m gathering idea for that.
    Cheers again for you time and involvement,

    Regards,
    Gaëtan



  2. Jimmy Auw Says:
    December 7th, 2009 at 20:45

    Hi,
    Decoupling bypass capacitor should be vary between 0.1-0.47uF.
    C5 is not an output coupling capacitor, but it’s a RC filter (Zobel).
    Thanks.



  3. Arie Says:
    December 8th, 2009 at 17:34

    Yeeeeehaaaaaaa….. Mantaaaafff!!!!
    Tunggu apalagi pak Jim…
    Fire up!!! :D

    Regards,
    Arie



  4. Arie Says:
    December 8th, 2009 at 17:36

    Btw, LM1875 nya sampe “ngilang”, belum ditambah pasukan gerbang item, makin “lenyap” tuh chip amp hahahaha… :D
    Maju terus pantang munduuurrr!!

    salam,
    Arie



  5. Jimmy Auw Says:
    December 8th, 2009 at 21:25

    Hehehe… belum keluar mood untuk ON-in-nya hehehe…
    Thanks.



  6. Gaëtan Says:
    December 9th, 2009 at 10:00

    Cheers for the info.
    From this I found that: A boucherot cell (or Zobel network) is an electronic filter, used in audio amplifiers to dampen out high frequency oscillations that might occur in the absence of loads at high frequencies. Named after Paul Boucherot a boucherot cell typically consists of a resistor and capacitor in series, that is usually placed across a load, for stability.
    And I am really curious on how to do it good. Any thought?



  7. Donnie Says:
    December 9th, 2009 at 12:06

    Gileee ko Jim two thumbs up..hehehe
    jd jantung dr amp nya sendiri (lm1875) cuma nyumbang kurang dr 1% dari total cost right ?

    regards,
    Donnie



  8. Jimmy Auw Says:
    December 9th, 2009 at 20:38

    Listening is believing. You can compare with and without Zobel. No best recipe for all.
    Thanks.



  9. Jimmy Auw Says:
    December 9th, 2009 at 20:38

    Mungkin less than 0.1%…
    Thanks.



  10. Damar.N Says:
    December 17th, 2009 at 12:19

    pak jim..itu bikin amp. kayak gitu ngabisin berapa ribu??..-rada tertarik nih..hehe..



  11. Jimmy Auw Says:
    December 17th, 2009 at 21:38

    Hehehe… silakan diitung aja bro harga per komponennya… Mungkin yang paling mahal ya Mundorf-nya yang hampir 2.5jt sepasang.
    Thanks.



  12. p31r Says:
    December 20th, 2009 at 05:37

    hahahaha this is most rediculous audio project i have ever seen. well good luck in your mission jim.



  13. yoel Says:
    December 25th, 2009 at 23:55

    wuihh.. kayanya benny emerald hrs bikinin PCB sesuai kebutuhan ko Jim neh… hehe… pisss…lanjoot..



  14. Jimmy Auw Says:
    December 26th, 2009 at 00:24

    Hehehe… saya lagi coba2 saja. Kalo bagus, mungkin akan bikin ulang dengan P2P atau bikin PCB sendiri yang lebih lega.
    Thanks.



  15. sopoiki Says:
    December 28th, 2009 at 02:45

    Oom JA,
    tanya nih. Kenapa pilih gainclone LM1875, kenapa bukan seri yang lain? Apa sih kelebihannya?



  16. Jimmy Auw Says:
    December 28th, 2009 at 21:16

    Ah saya tidak butuh watt besar-besar, jadi 1875 mestinya sudah cukup buat saya.



  17. arie Says:
    December 31st, 2009 at 21:15

    penasaran, sudah habis berapa duit tuh pak??



  18. Anonymous Says:
    January 1st, 2010 at 21:58

    just like V12 engine with greedy blower! can’t imagine how does the sound blow out from the muffler…:D

    Nice work,Pak…lanjut-gan…



  19. Jimmy Auw Says:
    January 1st, 2010 at 22:27

    He he he… bisa diitung sendiri dari harga per komponennya Pak…

    Thanks.



  20. Jimmy Auw Says:
    January 1st, 2010 at 22:28

    He he he bisa diitung sendiri dari harga per komponennya Pak.

    Thanks.



  21. even silver solder is mostly lead Says:
    January 9th, 2010 at 23:19

    Hi, love the site!!, looks like a great project and I have been looking for ideas for a ridiculous gainclone to use up some spare caps I have around, which were not enough for my builds of late as I only have 2 of each and everything has been balanced lately. I have 2 x VCAP OIMP 3.3uf, 2 x mundorf SIO .67uf (think thats the value), 2 x duelund 3.9uf VSF copper and plenty of blackgates and nichicon KZ.

    ridiculous enough?? :D one thing I did wonder, your method for tinning the chip leads really doesnt make sense to me, even silver/gold solder is mostly lead/tin and only 5% silver MAX (eichmann is 5% and is highest) the leads on the device will be copper under the tin (so I agree with scraping the coating) and copper is far better than lead, in fact I use solderless connections whenever I can because of this.

    the best way is solderless or weld with jewelers solder, only some components as it is a very hot process.

    regardless I look forward top seeing the finished amp and your impressions of the sound



  22. jeremy Says:
    January 9th, 2010 at 23:30

    wow I screwed up my name :D I made the post above. sorry I had lead on the brain, tin is what I meant not lead. and just saw that this one has a larger amount of silver, but is still only 9% compared to mostly tin, so I would still think that if you scrape off the tin on the lead and leave it like that or perhaps treat with deoxit it would be better. I doi understand the logic though and i’m most certainly not one of these doubting thomas’s :D



  23. Jimmy Auw Says:
    January 10th, 2010 at 11:04

    Even 0.1% of Gold on MCap Supreme Silver/Gold solder is enough to make your tin looked shining as Gold.
    http://jimmyauw.com/2009/11/22/mundorf-m-solder-supreme-silvergold/

    The rest is our preference.

    Thanks.



  24. Dan Lo-I Says:
    February 6th, 2010 at 06:15

    AYO!! AYO!! AYO!!
    Hihihi.. kompor Meleduk buat tanggal 20 Feb ntar



  25. Jimmy Auw Says:
    February 6th, 2010 at 15:25

    Huahaha… jadi penonton aja deh tgl 20 nanti mah. Uda banyak yang bawa amunisi ;)



  26. Jimmy’s Junkyard » Blog Archive » Disassembly Hickok 539B Says:
    February 8th, 2010 at 01:03

    [...] job, I prefer to leave my serious listening session for a while. So if you are waiting for my Gainclone Project initial impression, perhaps you must wait a little bit longer. Sorry to say. Also my Duelund CAST [...]



  27. fauzi Says:
    February 27th, 2010 at 22:11

    Salam kenal nama saya Fauzi, Pak Jimmy mao tanya gainclone LM 1875, kelasnya apa ya, kelas A atau AB. Thanks sebelumnya



  28. Jimmy Auw Says:
    March 1st, 2010 at 22:54

    Hi,
    Hampir semua chip-amp biasanya Class AB atau bahkan Class D.

    Thanks.



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