[Setmagic]

One of them have probably inverted polarity for some reasons... And always swell with 2 different polaritys, this is third one 16V 100uF all other are ok.

 

[Mr.HiAudio]

One of them have probably inverted polarity for some reasons... And always swell with 2 different polaritys, this is third one 16V 100uF all other are ok.

What result in sound?

 

[Setmagic]

What result in sound?

Capacitors in this situation don't give audible difference it's just a better filtering.
Under these there is still stock ones.
Must be compared side by side to stock device without improved filtering.
It's like buying High-End DAP you got what You pay and it's must be better than previous one who was few times cheaper

OPA1612 does audible difference it's just better, wider soundstage and higher fidelity of sound. Sound signature change. Old OP275 are really bad, have little grainy analog character but for sure this is first thing need to be replaced side by side with LDO.

This is first attempt and a lot of things need to be done like replacing all capacitors for better ones and double values.
Better LDO for sure this feel the same as DSDs it's crappy.

 

[Mr.HiAudio]

My small mod:

22nF to bypass on LDO and a bit wire for 3.5(reduces noise), AD826.
with 2.5 more current and the sound becomes more energetic, I like it very much

 

[Setmagic]

22nF to bypass on LDO and a bit wire for 3.5(reduces noise), AD826.
with 2.5 more current and the sound becomes more energetic, I like it very much

Nice idea with reduce noise.
Bypass LDO what it's mean?
Wire is needed for balanced as well?

I see during pressing buttons PCB is working and after that looks like banana. Technically strong pressing buttons nan kill Z4. It's really bad idea tin and large board only 4 screws on the corners baterry glued to center of PCB on chips side and hard pressing buttons...

 

[Mr.HiAudio]

Nice idea with reduce noise.
Bypass LDO what it's mean?
Wire is needed for balanced as well?

I see during pressing buttons PCB is working and after that looks like banana. Technically strong pressing buttons nan kill Z4.

The bypass is the 5th contact, it seems, I don't remember why it is called that the wire is only for 3.5, it will not work for balance, because there are different grounds

 

[cqtek]

Thank You it's just test but looks nice.
It's a trend in high end brands to put some Elna SIMLIC II for example good but cheap (about 1$ each).
They are celebrating it so why don't put some additional caps as well If I have space
Opa1612 changes a lot espacially space and separation.

Zishan creating cheap audio as possible using high end chips to mach 10 times more expensive stuff for fun.
Z4 have similar price as DSDs because use single board who is little slimer.
But is feel like lower build quality.
Maybe in the future we will see Z4 pro with better components but it will be cost 2-3 times more due changing production line and way more expensive original components.

For example:
Cheap Chinese LDO (power delivery chip) costs 2¢ and works
Really good LDO for audio from Texas Instruments cost 2$

LPF opamp op275 cost around 30¢
Best grade OPA1612 5$

Cheap Chinese Capacitors about 15¢ and works
Murata with same spec 3$

I understand that good components cost more. But if mass-produced, they could get a better price. If Z4 is worth, for example, 100$, could a special edition with all mods and better components be worth 150$? That would be a good price.
On the other hand, there is one thing I dislike about the Z4, the songs end abruptly a few milliseconds before they actually end. It's not very good at ending and starting songs.

 

[Setmagic]

I understand that good components cost more. But if mass-produced, they could get a better price. If Z4 is worth, for example, 100$, could a special edition with all mods and better components be worth 150$? That would be a good price.
On the other hand, there is one thing I dislike about the Z4, the songs end abruptly a few milliseconds before they actually end. It's not very good at ending and starting songs.

It's a bigger difference in cost than 50 dollars.

Maybe I will give a better example.
Components used to run Zishans are typical general purpose for electronics they just inside those big factory's robots, and they are cost nothing and just work as we see.
In Zishans DAC chips are most expensive than modules, CPU and last PCB assemble.

One of professional modder give me offer to rebuild Zishan from the best components and solutions for 1000$ to mach 3000$+ branded devices. Same components was very expensive, about half price. But we must stay with obscure software, navigation and LCD.
Mass production of that kind of player will be for example around 3 times cheaper, so Z4 will be cost 350$+

Do you think a selling will be still on the same level as device for 100$?
Main Zishans market isn't in Europe but in China, India, Africa and South America. This is "Hi-End like" device as cheap as possible.

You can put some mods to improve sound DIY by several dozen of dollars in quite simple way or spend few hundred redesigning all circuit using serious engineering skills.
This is main reason I stay with Zishans for now

 

[cqtek]

It's a bigger difference in cost than 50 dollars.

Maybe I will give a better example.
Components used to run Zishans are typical general purpose for electronics they just inside those big factory's robots, and they are cost nothing and just work as we see.
In Zishans DAC chips are most expensive than modules, CPU and last PCB assemble.

One of professional modder give me offer to rebuild Zishan from the best components and solutions for 1000$ to mach 3000$+ branded devices. Same components was very expensive, about half price. But we must stay with obscure software, navigation and LCD.
Mass production of that kind of player will be for example around 3 times cheaper, so Z4 will be cost 350$+

Do you think a selling will be still on the same level as device for 100$?
Main Zishans market isn't in Europe but in China, India, Africa and South America. This is "Hi-End like" device as cheap as possible.

You can put some mods to improve sound DIY by several dozen of dollars in quite simple way or spend few hundred redesigning all circuit using serious engineering skills.
This is main reason I stay with Zishans for now

As an electronics engineer, I can understand what you are talking about. If the Zishan with all the mods can cost $350, you would have to see how it compares to the HiBy R5 Saber and Shanling M3X. In terms of use, the Z4 is light years ahead of the HyBy R3 Pro. And that Zishan Z4 of 350$ should have fidelity as a priority. The frequency response graphs I've shown from the various IEMS I own show that this is not a priority. Would it cost $50 to reduce the output impedance so that this doesn't happen, among other things? Buying a product only to have to finish it yourself at home? That may be the goal for some, but not for most.
As a source this is not hi-fi, it comes close. It sounds good, yes, but fidelity is respect and this is not. And I think it sounds better than the R3 Pro, but I want to plug in headphones without having to worry that they are going to sound very different to what I am used to. I want them to sound the same, but better, not different, because to sound different I have 100 different headphones.
This is what I think and I don't want to get into polemics, because I respect this hobby a lot, I studied electronics because I loved audio. In the end, my working life led me to other fields for which I have better aptitudes. That's why I respect everyone who writes here and I like to create a good atmosphere to improve this product and I can't contribute with the mods, but I contribute with the information I can provide, as a grain of sand.
Anyway, as I said at the beginning, I like that the output impedance has dropped so much, now the Z4 is much more tolerable and I can enjoy more IEMS.

 

[Setmagic]

@cqtek so how about comparison to HiBy R3 Pro or R5 ?
You are confirm Zishan is ok for IEMs and it is sound good enought to compared few times more expensive players?

I can't compare to new good DAPs or DACs because I don't own any well known branded.

I have highly modded DSDs, old Fiio X3 and my custom desktop setup who was made long time ago.

 

[Merlin-PT]

One of them have probably inverted polarity for some reasons... And always swell with 2 different polaritys, this is third one 16V 100uF all other are ok.

You need to investigate that further with a multimeter.

As you know, putting the multimeter red probe in the (+) capacitor leg and the black probe in (-) cap leg (with circuit power on), must always give a (+) positive multimeter voltage reading. If you get a negative voltage reading it means the polarity is switched. We do this before soldering the polar caps , to identify the polarity locations in the PCB for each one of the polar caps we are putting.

Also see if the voltage absolute values are those expected, something else could be wrong.

 

[Setmagic]

You need to investigate that further with a multimeter.

As you know, putting the multimeter red probe in the (+) capacitor leg and the black probe in (-) cap leg (with circuit power on), must always give a (+) positive multimeter voltage reading. If you get a negative voltage reading it means the polarity is switched. We do this before soldering the polar caps , to identify the polarity locations in the PCB for each one of the polar caps we are putting.

Also see if the voltage absolute values are those expected, something else could be wrong.

I was sure it's correct polarity but I try to put second one inverted and same thing happen. This caps just run hot and after few minutes was burned (swollen).

 

[Merlin-PT]

I was sure it's correct polarity but I try to put second one inverted and same thing happen. This caps just run hot and after few minutes was burned (swollen).

So 1rst cap was bad and 2nd cap was good and was deliberated soldered with wrong polarity.
Let us know if the 3rd cap keeps working.

 

[Setmagic]

So 1rst cap was bad and 2nd cap was good and was deliberated soldered with wrong polarity.
Let us know if the 3rd cap keeps working.

Yes you are right. It was my mistake.

 

[cqtek]

@cqtek so how about comparison to HiBy R3 Pro or R5 ?
You are confirm Zishan is ok for IEMs and it is sound good enought to compared few times more expensive players?

I can't compare to new good DAPs or DACs because I don't own any well known branded.

I have highly modded DSDs, old Fiio X3 and my custom desktop setup who was made long time ago.

My HyBy R3 Pro inexplicably broke when I was testing it with some dongles. It has yet to be sent in for repair. Although, to tell the truth, it doesn't have the sound I'm looking for. I like the more analytical sound of Sabre. It was a pity because the Saber version came out a week after I bought the R3 Pro. So I was looking for alternatives. I was recently dropped off at a local tour in my country with the R5 Saber and it wasn't what I was looking for. It is a very narrow tablet with very small letters. And it has Android. I prefer the handling of the R3 Pro. The R5 Saber sounds better, but not as good as I expected. I was considering buying the Shanling M3X but I read that it has a warm sound, not what I'm looking for either. I was able to sell the F.Audio FA3 (another DAP that doesn't meet my minimum parameters) and this Z4 appeared. I bet on it and here we are. I insist that I don't regret the purchase. I can't compare it directly with the HiBy, but for balanced output its sound is quite good. At least, my feeling with it is good. I am happy with it. I suppose that later on, there will be some problems. Compared to the R5 Saber the sound is quite different. My impression with that one was not good either. I posted my impressions about it here, but I didn't translate the article:

https://hiendportable.com/2021/05/09/hiby-r5-saber-review/

But, for example, I'm testing the Tempotec Sonata E44 and well, I'm getting quite broken with the clarity, power and spatiality of its sound. They're two very different things, but that's my current comparison because that's what I have on the table right now.

Perhaps the use of these much cheaper passive components is to blame for the sound not being as refined as in other devices. It's not all about using the best DACS and it's clear that the best passive components demonstrate that difference, as well as other dedicated chips. Well, that's clear to you, better than me. So, I think the E44 has a cleaner sound than the Z4 because of balanced. It is possible that the level of distortion has something to do with it. So the use of the Z4 with IEMS, should be with those that are not very delicate. BA and low impedance multi drivers reveal a dirtier sound and higher distortion. It's something I'm noticing now with the Rose QT9 MK2 and badly recorded music like this: