[Setmagic]

I also noticed that the volume increased slightly. I redid the post above. if there is a new firmware in the cloud then bark me to know, I will download it

Thank You. It seems all new firmware will be updated here:

https://pan.baidu.com/s/1l2eHKDvs3eVuZFjh440OnQ

Password: z4z4

I'm curious how it's possible to work balanced and single ended same time only by software update. Same as DSDs.
I plugged balanced headphones and single ended and was working in parallel.
When balanced is turn off SE remain same way. According to Mr.HiAudio SE mod 3,5 PO needed different ground to sounds better. Now I'm surprised AUX 3,5 and Headphone out 3,5 sounds in similar volume level. 3,5 Headphones have more energy, but volume is very close.
I'm most happy about no more cracking sound when power up or down.

 

[dricas_007]

The Baidu link above is not working anymore, but I manage to download the firmware from previous page. Thanks

 

[Amos Isaac]

Small MOD V1.2 update


OPA1622
4x 10uF X7R muRata
4x 10uF Elna SIMLIC II RFS
4x 1uF X7R muRata
4x 100nF NP0 muRata
4x 56nF metal film foil Panasonic

AD8620 (was OPA1656 OPA2134 OPA1612 instead OP275)
2x 10uF
2x 1uF
2x 100nF

DAC ES9038
4x 100uF X7R
4x 47uF X5R
12x 100nF C0G

LDO TI LP5907 3.3 x2 (instead Chinese one)
4x 2,2uF X7R
4x 100nF

Filtering main PSU ~9V
2x 180uF X5R
1x 1000uF Rubycon Ultra Low ESR
1x 1uF
1x 100nF

filtering digital ~4V
1x 180uF
1x 1uF
1x 100nF

It's still under develop.
Testing how much separate element affect sound and stability, I need few days

How do you find the sound so far? How does it play with higher impedence headphones? Really admire your work.

 

[Setmagic]

The Baidu link above is not working anymore, but I manage to download the firmware from previous page. Thanks

I fixed the link but due to Chinese and common problems with downloads I will update first post as always.

How do you find the sound so far? How does it play with higher impedence headphones? Really admire your work.

It's great for high impedance HP as a stock as well.
MOD of Z4 is not as visible as Zishan DSDs who had big design problems.

Main sound solution for Z4 is still LDO + LPF that's open sound space and separation and higher overall sound grade.
Replacing for better and reconfigure amount of capacitors on analog power supply is also important.
Sound will be smoother without slightly digital sandiness and metallic ringing.
More capacitors for DACs working, too.
Cant tell about 1000uF electrolytic in 9V main PSU maybe not necessary, but I will leave it.
4 small electrolytic in opa1622 are more necessary for base energy at higher volume.
Texas Instruments recommend 10uF, but always better to have good muRata MLCC X7R and C0G 10uF + 100nF paired with top 10uF electrolytic. I had 220uF, but sound was a little muffed.

I have plan for smallest ones for in audio rail, there is 2,2nF and 680pF.
They look like X7R and have good parameters, but I will change it anyway to C0G as best can fit.

 

[Mr.HiAudio]

4 small electrolytic in opa1622 are more necessary for base energy at higher volume.
Texas Instruments recommend 10uF, but always better to have good muRata MLCC X7R and C0G 10uF + 100nF paired with top 10uF electrolytic

Please, can you show in the photo (you can take a photo of any board) where you need to put them?

 

[Setmagic]

Please, can you show in the photo (you can take a photo of any board) where you need to put them?

 

[Amos Isaac]

Small MOD V1.2 update


OPA1622
4x 10uF X7R muRata
4x 10uF Elna SIMLIC II RFS
4x 1uF X7R muRata
4x 100nF NP0 muRata
4x 56nF metal film foil Panasonic

AD8620 (was OPA1656 OPA2134 OPA1612 instead OP275)
2x 10uF
2x 1uF
2x 100nF

DAC ES9038
4x 100uF X7R
4x 47uF X5R
12x 100nF C0G

LDO TI LP5907 3.3 x2 (instead Chinese one)
4x 2,2uF X7R
4x 100nF

Filtering main PSU ~9V
2x 180uF X5R
1x 1000uF Rubycon Ultra Low ESR
1x 1uF
1x 100nF

filtering digital ~4V
1x 180uF
1x 1uF
1x 100nF

It's still under develop.
Testing how much separate element affect sound and stability, I need few days

How do you like the Z4 with these mods so far? Sound wise, how is it compared to stock?

 

[Setmagic]

How do you like the Z4 with these mods so far? Sound wise, how is it compared to stock?

For side by side comparison with 100% accuracy, what's exactly changed, I need a second stock Z4 in same moment
I can say I like it more - wider sound stage, deeper base, 3D holographic is more present, and it's overall better.
Especially power line 3.3V and low pass filter done most of the improvements.

 

[Amos Isaac]

For side by side comparison with 100% accuracy, what's exactly changed, I need a second stock Z4 in same moment
I can say I like it more - wider sound stage, deeper base, 3D holographic is more present, and it's overall better.
Especially power line 3.3V and low pass filter done most of the improvements.

That sounds cool. Would love to try out modded versions.

 

[Setmagic]

@Amos Isaac
You can try contact with Your local electronic service and ask for that kind of work on Your Z4.

Cost of parts was around 25$

 

[Setmagic]

Next modification update.
Replacing China LDO in digital board to Texas Instruments LP5907 with better filtering C0G+X7R instead X5Y.
No audible differences, or system speed boost but placebo works as always
Old had PSRR ~60 new have ~80 so it's matter for sure.

 

[Setmagic]

Replaced all capacitors in Audio rail from X5Y to G0C. I'm sorry for quality, it's 20x digital zoom.



This is size comparison old upper and bottom new one muRata G0C 2,2nF.
Sounds amazing! Separation and black background. Especially in high frequency.
Audible improvement over stock ones.

@edit
Nerby OPA1622 are also tiny "680pF" but they was inaccurate measured 612 and 634pF. MuRata have 665 and 671pF and it's C0G.

 

[Mr.HiAudio]

Replaced all capacitors in Audio rail from X5Y to G0C. I'm sorry for quality, it's 20x digital zoom.



This is size comparison old upper and bottom new one muRata G0C 2,2nF.
Sounds amazing! Separation and black background. Especially in high frequency.
Audible improvement over stock ones.

@edit
Nerby OPA1622 are also tiny "680pF" but they was inaccurate measured 612 and 634pF. MuRata have 665 and 671pF and it's C0G.

what denominations did you use? and, can you show them on the board by designating? or are there any ready-made schemes?

 

[Setmagic]

what denominations did you use? and, can you show them on the board by designating? or are there any ready-made schemes?

Closer LPF on both sides 4x 680pF 50Volts C0G 5% GCM2165C1H681JA16D
After resistors farest: 2x 2200pF 50Volts C0G 5% GCM2165C1H222JA16D
OPA1622 upper 2x 680pF 50Volts C0G 5% GCM2165C1H681JA16D

 

[Zbiten]

All hello. Whats wrong? My Z4 just flash white screen, music on (Round button work), but nothing on screen. 21.08 i was updated fw to 1.02, but after it worked before today.
Video for demonstrate.
https://disk.yandex.ru/i/UWnb0yh--2eVpA