The Zishan dsd's corner

[slavalun]

Is TPA6120A2 any good?

Prefers high-resistance load (from 60 Ohm), with decreasing resistance, harmonic distortion increases

 

[Merlin-PT]

I'll give it a try in the near future, my favorite earbuds have DIY 400ohm drivers.
Somehow I'm not expecting better sound signature than some other TI and AD opamps.
But mainly you say they are not very good were they could use high current, with low impedance drivers.

 

[moshe tes]

 

[moshe tes]

My idea for what I want to do with my Zishan. To have the 18650 cells on the sides so that it is pocketable. What do you think?

 

[Setmagic]

My idea for what I want to do with my Zishan. To have the 18650 cells on the sides so that it is pocketable. What do you think?

It's depends of your pocket
This is most reasonable placing of accu you can did for portable use other than powerbank. Why you don't want to use powerbank instead?

 

[Merlin-PT]

@moshe tes

There's also the option of this battery with same size, but double the thickness and double the capacity of the original. It gives 6000mAh for 9.6mm thickness. I never tried it.
https://www.aliexpress.com/item/33011185788.html
https://www.aliexpress.com/item/32795911992.html

The internal battery could be removed, giving additional ~5mm inside space for bigger cap mods and the new 9.6mm battery could be mounted outside the original case back.
Then a lid could be cut from another same size generic case bought in AliExp and just put over the back.
The back lid would be cut in the new case like this photo:
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-109#post-14749153

If you don't need the 5mm internal space just put the new batt inside and add only 5mm thickness to the original case.

 

[moshe tes]

@moshe tes

There's also the option of this battery with same size, but double the thickness and double the capacity of the original. It gives 6000mAh for 9.6mm thickness. I never tried it.
https://www.aliexpress.com/item/33011185788.html
https://www.aliexpress.com/item/32795911992.html

The internal battery could be removed, giving additional ~5mm inside space for bigger cap mods and the new 9.6mm battery could be mounted outside the original case back.
Then a lid could be cut from another same size generic case bought in AliExp and just put over the back.
The back lid would be cut in the new case like this photo:
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-109#post-14749153

If you don't need the 5mm internal space just put the new batt inside and add only 5mm thickness to the original case.

I need the space inside, that's why I am doing this. I will be using 1000uF caps on vref that need the extra height. I thought about using bigger LiPos like the ones you linked, I just don't trust cheap chinese LiPo batteries. As you probably know, LiPo tend to be more volatile than your regular Li-ion, so better to go with a known brand. As far as my model, it fits in most pockets. I was going to put the batteries on the back initially, but that would have made it non-portable.

 

[Merlin-PT]

Maybe this will interest some:
https://www.head-fi.org/threads/zishan-z3-hi-fi-player-thread.911846/page-3#post-15977278
New Z3 "version on Ali and Tao with Cirrus Logic cs43198".

 

[moshe tes]

Maybe this will interest some:
https://www.head-fi.org/threads/zishan-z3-hi-fi-player-thread.911846/page-3#post-15977278
New Z3 "version on Ali and Tao with Cirrus Logic cs43198".

Oh I have the Z3 AK4493 version that has only a few mods. Changed the LPF opamp to OPA1612 and headphone driver to OPA1622. It is definitely more detailed, but still not as detailed as it could be and not as impactful as I'd like it to be. I still need to figure out the circuitry on it. I followed some of your advice on the Z3 forum but not enough information. I am still not sure how it gets +-13V.

 

[moshe tes]

Btw, have you found an ADI alternative to the B628XX regulator that comes before the 5V LDO? I narrowed it down on this page but I'm not sure which one to select.

https://www.analog.com/en/parametri...ad SC70|6-Lead SOT-23|6-Lead TSOT&p5362=Boost

 

[moshe tes]

Why is there continuity between the left and right channels near the 3.5mm output jack of the Zishan DSD. Is that normal? I thought they were supposed to be separate. There seems to be continuity between both channels and also between both channels and ground. I am confused. Also could you please explain the interaction between the relay and the 3.5mm jack? Does the output from the buffer go to the relay? If so, is it both Left and Right or Ground or all? I imagine the FET near the relay is used to switch the relay?

 

[DBaldock9]

Why is there continuity between the left and right channels near the 3.5mm output jack of the Zishan DSD. Is that normal? I thought they were supposed to be separate. There seems to be continuity between both channels and also between both channels and ground. I am confused. Also could you please explain the interaction between the relay and the 3.5mm jack? Does the output from the buffer go to the relay? If so, is it both Left and Right or Ground or all? I imagine the FET near the relay is used to switch the relay?

The relay on these devices creates a dead-short across the output of the amplifier stage at power-up and power-down, to keep any "thump" sounds from reaching the earphones.

 

[Merlin-PT]

@moshe tes
B628XX is MT3608, download MT3608 datasheet to read how it works.
Regarding Z3, when you decide to mod it more ask in Z3 thread, it also uses B628XX (MT3608).
More than 1,5 years ago I searched all brands in arrow (in stock items) for a pin compatible alternative to B628XX (MT3608) and didn't found any. Don't know now.
In DSD it isn't that important replacing B628XX because they use a 5V LDO after B628XX and we replace the LDO for a better one.

The relay is explained in the links I sent you in previous relies.
- The relay:
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-160#post-15025178
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-202#post-15945102
Here I rewrite what Ivan said in the first link:
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-160#post-15025647

 

[londere]

hi
in usb dac mode, filters of dac works ?thanks in advance

When USB mode is on, the EQ is overridden by your pc custom settings, for digital filter implemented on DAC still there due to HW/SW implementation of i2c in RTOS.

@Merlin-PT , @slavalun , @maxifuny I admire your in modding this device, I had a question, well a pair of, 1.- It's possible the implementation of an I/V stage on the DSD's 4499 or 4497?, such as the circuit proposed in the TPA6120A2 and Muses02?, 2.-If that is the case which IC AMP could you recommend? In advance thanks!!

By the way @Merlin-PT I bought some items from the store that you post for the TPA61XXXX it's a good seller. Also, he claims to be a "good friend of Zishan".

 

[citral23]

I had crashing back when I bought Z1, Z2, DSD, only thing that solved it for me was deleting all music files metadata (used some software for that), sometimes metadata with song info fields or image is corrupted or too big and the fw doesn't account for that. I think I even had to delete 1 or 2 music files, because zishan would always crash on them.
After this was done, I didn't had any crash ever again in any of them.

Finally got around doing this, and not only did it get rid of crashes, but my dual 4497 now boots in 2 seconds with a 256G card with around 180G of music, very nice, thanks.