[beehavior]

black on black. still waiting my gold knob from AE

 

[wastan]

I still can't make z1 as dac on Android

Does your Android device support usb otg? If it doesn't, it won't work for you.

 

[LaughMoreDaily]

What is your favourite opamp in your Z1's? Mine is AD8620 so far.

 

[Merlin-PT]

I don't have AD8620 yet, I ended up using LME49720ha in Z1.

 

[DBaldock9]

It's been a while since my Z1 was assembled and usable, but I remember liking the LME49720HA and the Burson V5i-D.

 

[LaughMoreDaily]

It's been a while since my Z1 was assembled and usable, but I remember liking the LME49720HA and the Burson V5i-D.

The 49720HA is okay but there are much better sounding opamps. AD8620 is good but there may be better ones...

 

[DBaldock9]

The 49720HA is okay but there are much better sounding opamps. AD8620 is good but there may be better ones...

I have bought better op-amps since then (they're listed in my profile), but my Z1 has been disassembled for a while.

 

[Merlin-PT]

The 49720HA is okay but there are much better sounding opamps. AD8620 is good but there may be better ones...

I have to agree, z1 was the only dap I could use the 49720ha, in better daps other opamps sound better to me.
Still in Z1 context I liked it.
I liked my stock z1 very much, it is very musical. After replacing the opamp and caps it got a bit more detail, but I couldn't get much more of it. I don't think I'll use a better opamp in z1, my modded z2 has much more detail, to me it's another level. I liked z1 a lot, but with z2, I don't use z1.

 

[Ivan TT]

Whoever arranged to get this thread re-opened, thank you very much!
Update:
All kudos go to @Merlin-PT !

 

[LaughMoreDaily]

I don't think I'll use a better opamp in z1, my modded z2 has much more detail, to me it's another level. I liked z1 a lot, but with z2, I don't use z1.

I heard something weird recently... that Z2 is made for headphones and not iems with low ohms.

 

[Merlin-PT]

I've read that the zishan high output impedance is not good for low impedance BA iems, but I can't comment on that, I didn't try my iems, because I like to use earbuds now.

 

[IcedFrosty]

Finally this zishan thread is reopened! Now I can join zishan community in head fi!

Anyway, I like both z1 and z2. The zishan z3 pro seems promising cuz it comes with ak4493. But here's what I've been wondering for a while, does the DAC implementation on zishan products are properly implemented? Especially in the z3, the size if the pcb is smaller and there's only 2 capacitors. I'm a newbie here know capacitor game, can someone explain it to me what does capacitors do and how are they being implemented?

Thanks

 

[Merlin-PT]

This is my limited understanding, please feel free to add or correct anything.

Some of the capacitors uses related to all zishan models that come to mind are:

- Power supply reserve/storage/smoothing: Caps can be used as _local_ power reserve. As the word says they are used as local power reserve and to supply smooth stable voltage, to try to keep voltage as stable as possible. They are used in parallel with the power supply lines and ground.

You need them near the opamps power supply pins, connected in parallel with the power supply pins and ground. They try to supply a steady smooth power to the opamp. One upgrade possible is to add (where missing) or increase the capacity.

They are also used in stm32 power supply pins, stm32 datasheet recommends more capacitance than zishan uses, so one of the upgrades is increase the stm32 power supply pins caps capacitance. This is important, not only to stm32 operation, but to the rest of the circuit. If the cpu needs current fast and we don't have these, it can make power fluctuations in the rest of the circuit.

They are also used in the DACs power supply lines, there are a lot of them in z1, z2, z3 and DSD around the DAC, we can read the dac datasheet and implement the recommended capacitance and cap type in the circuit, this is one of the possible zishan upgrades.

- Coupling capacitors: In series with the signal path, capacitors pass AC, but block DC signals, so they can be used to separate these components, to pass the music (AC) and block DC. To do this they are connected in series with the audio signal path.

These are the electrolytic capacitor that people usually change in zishan.
The DC component we want to block (a DC voltage), displaces the speaker cone from it's central position, it can cause distortion or even kill the speaker.
When this caps are used they "spoil" sound to some extent, so people change them to change sound color to personal taste or to try to minimize changes.
Also this signal couple caps, have a side effect of acting as freq. filters, so their capacitance must be calculated not to filter the audio freq. band.
In sum, in some circuits they are needed to block DC in audio path, but they "change/degrade" sound and act like a frequency filter.
Their capacitance must be calculated not to filter the audio band and people change them to minimize their effect in sound or to color sound to personal preference.

- High pass and low pass filters:
Here caps are used to make filters and selected the audio freq. band that will be amplified and heard.

- Bypass capacitors:
In parallel with power supply lines and ground, a capacitor is used to short AC signals to ground, they filter/remove interference. This way AC noise present in DC can be removed and we have a cleaner power supply. In zishan we can see 0.1uF ceramic bypass capacitors in parallel with some, but not all of power reserve caps. One upgrade can be to add some more bypass caps where needed. They need to be located very close (ideally at the legs) to the power supply legs of the opamps, dac, cpu, etc.

 

[D0rk!n]

Atlas this thread reopened

 

[D0rk!n]

Currently I'm using Texas Instrument OPA1678 on my Zishan Z1 with Toneking TP16, K's64, Vido Earbuds

IMPRESSION (Subjective):
Neutral sounding opamp, low noise/ black background, it is transparent does not add any sound coloration. Both ends (lows and highs frequency region) are extended. There is a sub-bass if the song has it (especially EDM and modern metal) and its well-controlled and medium to fast decay and can go deep. Kick drums is tight and controlled with fast decay (this is good if you’re into Metal music). Tom-toms (Rack and Floor-Toms) are tight, full bodied and controlled with a good low rumble on floor-toms and it decays smoothly. Bass guitar is rounded and controlled. Both male and female vocals is smooth, no harshness. Snare drum is snappy and has a body. Guitars sounds natural and well-articulated fast riffs (passages) can be heard clearly. Hi-hats, cymbals (crashes/splashes) do not sound artificially metallic, not fatiguing, and it is controlled with medium to fast decay. Keyboards and synths sits-well in the mixed and does not masked out other instruments and vocals. The soundstage of this OpAmp is wide and with average depth. Imaging is holographic (3D’ish) every instruments/vocals are place well and you can pin-point it accurately in the soundstage. Layering is also good even on busy parts of the song you can hear each clearly. Separation is good also stereo panning of each instruments/vocals are accurately presented. I think this OpAmp can pair well to any sound signature of earphones/headphones so colouration depends on the mixed and the tonality of the earphones/headphones. Can be used for long listening session.

Comparison to stock opamp (TI NE5532P) of Zishan Z1 and also to Hybrid OpAmp Burson V5i:
TI OPA1678 is smoother because mids and highs on the stock opamp are grainy and rough. No bass bleed on the mids compare to stock opamp that muddied the mids. Soundstage is wider than the stock opamp. I could say that OPA1678 is on par to Burson V5i on soundstage, imaging, layering and separation, though Burson V5i has a slight edge on soundstage, imaging and more intimate vocal presentation.