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:
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) 👍
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?
Has anyone else swapped the opamps on this amp?
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!
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!
Yes, I am (but not an active member). It's been a long time since I visited that site, will have a look!
Nice work on the RCA and input cable 👍
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:
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?).
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:
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?).
Yes LF353's. I've only got a basic grasp on how amps work TBH. I don't know how to measure an amp. Just heard good things about these Sparkos so I'll give them a go! 😁 I'll report back!
I would stay away from those opamps, as they are just balancing out the DC at the output. As long as one doesn't know exactly what and how it's working, it seems pretty useless to me.
Anyway, I replaced the binding posts with some better copper ones and I am surprised that it made a difference. A little bit more dynamics and clarity I would say. Currently collecting parts for next stage, first I will target the power supply with additional wires to the amplifier board, as there are free spots to add those wires. Also will add parallel Nichicon 220uf on the power supply.
But I think the input capacitors and the 51 Ohm in series after them will have the biggest effect, I will try to squeeze in some good caps and replace the resistors with Audio Note Niobium, which are expensive, but it's only 2 pieces and this amp deserves best parts.
Anyway, I replaced the binding posts with some better copper ones and I am surprised that it made a difference. A little bit more dynamics and clarity I would say. Currently collecting parts for next stage, first I will target the power supply with additional wires to the amplifier board, as there are free spots to add those wires. Also will add parallel Nichicon 220uf on the power supply.
But I think the input capacitors and the 51 Ohm in series after them will have the biggest effect, I will try to squeeze in some good caps and replace the resistors with Audio Note Niobium, which are expensive, but it's only 2 pieces and this amp deserves best parts.
Thanks for the advice. I looked it up (AI) and it seems the OPAMP for DC won't make much difference. I'll hold off on that but I'm interested in what you've suggested about the caps and resistors.
Interesting, looking forward to your experience (and pics?) for these mods.
Yes, maybe it is useless (although the OPA1656 is faster etc than the LF353, but all depends on the circuit design). Probably will change it back after a while to compare anyway.
What binding posts did you use?
I think I will change my RCA sockets as well, these Viborg ones look nice! I do prefer a soldered connection, so probably will use the RC101R.
Maybe someone from the zelfbouwaudio.nl forum members also has one and can bring it to a listening day? Or do you mean my modded version?
I bought these: Binding post
They seem to be real copper, one has to be suspicious when it comes to descriptions at AliExpress.
Pics will follow, but it will take some time.
They seem to be real copper, one has to be suspicious when it comes to descriptions at AliExpress.
Pics will follow, but it will take some time.
Yea the Viborg ones are nice. I've got some Viborg rhodium binding posts on the way too.
Looking at the schematic am I right in saying there are 2 3.3uf input caps per channel? I've had a look at the AN resistors and the closest value they have is 47R. Would that be subtitle? Maybe Vishay Z foil are an option too.
Yes, it is 2 3.3uf caps for whatever reason instead of one 6.8. Those Z foils should be great as well, but I like those AN for their smooth, detailed and musical character. I guess 47R should be fine as well, I will try with these.
And for the binding posts and RCA sockets: I like that they have a screw connection, for example a crimped connection is always better than a solder joint. I can imagine that this valid for those screw connections as well.
And for the binding posts and RCA sockets: I like that they have a screw connection, for example a crimped connection is always better than a solder joint. I can imagine that this valid for those screw connections as well.
Thanks, I can't get the niobums over here in less than 100k. I can get the silver tantalums in 47R but they will end costing well of 100 euros for a pair. I got a good price on the Zfoils so I got them for now. Might pick up some AN ones when I visit back home in UK for the summer. Wonder what decent 3.3uf caps would fit?