Replace Dartzeel NHB-108 clone AC inlet connecter/power connector

Thanks and you're welcome! I think I do hear some improvements, but they are subtle (but very hard to remember how it sounded before; A/B testing is not really possible). Anyway, they are fun to do 🙂I found a video of the d9 pro master, and this version is very similar to the D5 pro, but had some similar improvements I did as well. And the reviewer said it sounded better than the D5 pro (see
). Here is a picture of the materials for the mods they did:

Se6230a171fca45f098293ac7acf1f0bcC.jpg_960x960q75.jpg_.png


In only have not changed the fuses (yet), and my cables are much thicker (they claim to use one crystal taiwanese copper; mine are all mogami copper). Maybe I will change the fuses, but not sure that would make a difference (and I do not want to pay $200 for a fuse like the the synergistic research purple fuse). Maybe I will use the same as in this picture (I think these are Schurter SMD-SPT) or some highly rated audiophile fuses from AE.
Anyway, it is still the best amplifier I have for sure! Have fun modding yours, I think you will not regret it (and you already have the BCs installed) 👍
 
One of the last things I changed is an opamp switch. I replaced the LF353 for the OPA1656. See pictures for detail, easy to do. I am not sure if this is an improvement. Always hard to recall how it sounded before, but I think the sound is now a bit thinner. But will give these some time, to see if this grows on me. On paper these are superior, but maybe for this design it is not a good choice.

Has anyone else swapped the opamps on this amp?

IMG_7238.jpg
IMG_7240.jpg
IMG_7242.jpg
 
  • Like
Reactions: Neiljd990
Changed the RCA sockets and input cables. Noticeable improvement across the board! Very happy. Everything is bigger and more detailed. I used Xangsane SP9001 silver cable and Viborg rhodium RCA sockets.

I'm going to order either the Sparkos SS3602 or SS2590 opamps next then still got the binding posts, output cables and IEC to do. Need to find a reasonably priced thicker gauge silver cable for the output. Probably Xangsane again. I don't mind putting a bit of money into this amp. It's so good!

dde687063e5ea21a5c6b0111b5449a7.jpg
 
  • Like
Reactions: niekos
Nice work on the RCA and input cable 👍
I'm going to order either the Sparkos SS3602 or SS2590 opamps
Keep us posted about your experience with these opamps, I am very curious how these will sound. Do you also have the LF353 in your amp?

Also, I found this interesting subject on opamp swapping here: https://www.diyaudio.com/community/threads/swapping-op-amps-you-have-checked-to-see-its-stable-havent-you.191389/.

Since I do not know the circuit, this might also be happening in my case (oscillation). I found this an interesting part @Mooly writes:
Would you know it was unstable by listening ? Well actually, you may not, and may put the change in sound down to the op-amp ! The AD797 certainly sounded over bright and thin but I can imagine some saying, "hey listen to that extra detail" it just shows how murky and dull the 5534 was. A bit extreme maybe, but you see my point.

Well, I do not know, I do know it now sounds differently. And you get used to different. But I would like to know that nothing is going wrong also, so I will probably get an oscilloscope to measure the effect (wanted to do this anyway; any tips for an good entry oscilloscope?).