[NotKunvinced]

I am planning to get this one, really looks like a cheap and different dac with a good chip inside shoud pair well with tempotec V1.

Exactly what I was thinking......

 

[BubisUK]

They will have them on ali summer sale, so that is another reason to get tempted

 

[BubisUK]

Well, I pulled a trigger on one Got it for 28$ and some change, will post my impression here when it arrives

 

[bystander]

Same. These specs for such price are not bad at all. I wonder if it will actually work like I think it should. Also looks like there's no way to know the output impedance but whatever, let's try.

upd. OI is 10 ohm. Source: Nicehck store private message. Had to cancel.

 

[IcedFrosty]

Alright, U1 finally on it's way to me. I wanted to be the first one to have it, but not anymore. I guess i won't be the first one to have the U1 here, haha...

Well, I pulled a trigger on one Got it for 28$ and some change, will post my impression here when it arrives

Glad to hear that you've pulled the trigger. Mine's also having it's way to me.

Sure, you should share your impression once it arrived

Same. These specs for such price are not bad at all. I wonder if it will actually work like I think it should. Also looks like there's no way to know the output impedance but whatever, let's try.

upd. OI is 10 ohm. Source: Nicehck store private message. Had to cancel.

Oh, 10Ω output impedance, it's the same as the T1 (and the DSDs also i think). Is it that bad?

 

[bystander]

Alright, U1 finally on it's way to me. I wanted to be the first one to have it, but not anymore. I guess i won't be the first one to have the U1 here, haha...


Glad to hear that you've pulled the trigger. Mine's also having it's way to me.

Sure, you should share your impression once it arrived

Oh, 10Ω output impedance, it's the same as the T1 (and the DSDs also i think). Is it that bad?

It's a bit high for iem needs. I could use it for 400i but there will be a fairly priced desktop solution from topping soon. Battery powered device was a gamble to me anyway. Still thanks for the info. Hope your units will work fine.

 

[IcedFrosty]

It's a bit high for iem needs. I could use it for 400i but there will be a fairly priced desktop solution from topping soon. Battery powered device was a gamble to me anyway. Still thanks for the info. Hope your units will work fine.

I see. I used my TFZ with my T1 and it's alright, but yeah, it has a very audible noise. Maybe this is the price of cheap chi-fi. I was really hoping you join this game, but oh well.

Thanks, bystander.

 

[DBaldock9]

Alright, U1 finally on it's way to me. I wanted to be the first one to have it, but not anymore. I guess i won't be the first one to have the U1 here, haha...


Glad to hear that you've pulled the trigger. Mine's also having it's way to me.

Sure, you should share your impression once it arrived

Oh, 10Ω output impedance, it's the same as the T1 (and the DSDs also i think). Is it that bad?

The DSD (single AK4497) has 22-Ohm Series Resistors on the Balanced Output lines, so 44-Ohms per channel.

 

[IcedFrosty]

The DSD (single AK4497) has 22-Ohm Series Resistors on the Balanced Output lines, so 44-Ohms per channel.

Such a high output impedance there, i think it's true that Zishan and Walnut devices were made for low sensitivity, high impedance cans. I wonder why they used such high resistors on the output. Dave, does the DSD caused noise on IEMs?

 

[DBaldock9]

Once I finish modifying the analog circuits of one of the Single AK4497 DSD units, I'll be able to compare it to the unit with the unmodified analog circuits. I do intend to upgrade the LDO regulators and oscillators on both units - so the only differences will be the op-amp connections, capacitors, and series resistors in the analog circuits.
.
Generally speaking - when I compared multi-BA hybrid IEMs on DAPs with higher & lower output resistance, it seemed like the low Bass was better on the units with lower series resistance.

 

[BubisUK]

Once I finish modifying the analog circuits of one of the Single AK4497 DSD units, I'll be able to compare it to the unit with the unmodified analog circuits. I do intend to upgrade the LDO regulators and oscillators on both units - so the only differences will be the op-amp connections, capacitors, and series resistors in the analog circuits.
.
Generally speaking - when I compared multi-BA hybrid IEMs on DAPs with higher & lower output resistance, it seemed like the low Bass was better on the units with lower series resistance.

Is there alot stuff to change? I am good with soldering iron, but would not know what to change in an amp but would not mind modifying my U1 if I would know what to change

 

[rsusid]

ZiShan U1
New portable USB DAC+AMP from ZiShan which is their first dedicated external DAC+AMP, featuring:

- PCM decoding up to 32bit/384kHz
- DSD decoding up to 1bit/5.6MHz
- AK4493EQ DAC
- OP275 LPF (soldered)
- OP275 AMP (soldered)
- Dual crystal oscillator
- Atmel Atsam Microcontroller
- Xilinx FPGA (not exactly sure but it seems to be)
- 3.5mm Power Output (PO)
- 3.5mm Line Output (LO)
- Dual USB-C ports; Charging port (I/O) and Data USB DAC port (Input)
- 3.8V 884566 4200mAh Battery
- ±9V Power supply
- Elna caps coupling
- Volume knob
- Supports QC2.0/QC3.0/MTK PE/USB PD quick charging and output charge (In other away, can be used as a power/battery bank)
- Portable size at 100mm × 50mm × 20mm (Length × Widht × Thickness)

Full Description (straight from ZiShan):
Zishan suddenly came up with a USB decoder, so the model named U1 was launched.

Due to the meager profit, only one computer data cable is standard, please be aware.

With so many similar products on the market, what are the characteristics of U1?

1. U1 is a 4200mAh fast charge and quick release two-way charging treasure, does not consume mobile phone power, and can also quickly charge the mobile phone.

U1 adopts the latest fast charging chip IP5332
Integrated QC2.0 / QC3.0 output fast charging protocol
Integrated FCP input / output fast charging protocol
Integrated AFC input / output fast charging protocol
Integrated SFCP output fast charging protocol
Integrated MTK PE + 1.1 & 2.0 output fast charging protocol
Integrated USB C DRP protocol, support input and output fast charge
Compatible with BC1.2, Apple, Samsung mobile phone fast charge

As shown in FIG,
When charging U1, the fast charging head wiring is inserted into the CHARGE port.
When charging the phone with U1, you need to connect the two-head TYPEC to the U1 CHARGE port and the USB port of the phone.
The button is the power indicator, click to see the current power.

2. U1 is a daughter card compatible with the Italian Amanero digital interface
Zishan's preferred dual crystal + CPLD I2S solution, which leads to I2S key signals for players to DIY. Just want to connect to the computer and do not want to toss the buyer to unplug the battery directly, short J1 can be used as a "desktop" USB decoder, U1 is at this time The USB DAC port takes power. The configuration of this decoder is not simple, but the Amanero digital interface + full blood AK4493EQ + Tu 9V power supply + dual OP275 + native 3.5 LineOut + HIFI standard amp for the tube amp! It is convenient for everyone to pick up the speaker.
The default firmware is compatible with CPLD_for_1080 + DSD512 × 48 × 44
Driver compatible with: see in the links section below (A)

Support up to PCM 384K 32Bit
The DSD hard solution only guarantees DSD128, because the profit is meager, other DSD256 DSD512 settings must be tossed by Baidu or Google, search for the keyword "Italian amanero foobar2000 settings", very much information. Important things said three times: meager profit, no technical support! Low profits, no technical support! Low profits, no technical support! The following DSD setting links are for reference only.
Link: see in the links section below (B)

3. U1 is an Android Apple "little tail"
Android phones directly use dual TYPE-C cables, one end is connected to the phone TYPE-C port, and the other is connected to the U1 USB DAC port. Generally, Haibei is used to open USB exclusive or USB Audio Player PRO. Please note that there are many Android phone models and system versions There are many, not necessarily all support USB DAC output, these are Zishan can not control, need buyers toss, it is recommended to first understand whether their mobile phone supports USB DAC output, U1 only guarantees to connect to the computer.
Android software link: see in the links section below (C)

Apple phones need to buy a Lighting to Type-C cable, or buy an Apple camera kit, one end connected to the Apple phone Lighting port and the other connected to the U1 USB DAC port, Apple plugs in is the USB DAC output, and the playback software is free. If there is no recognition or use Disconnected after a few tens of seconds, indicating that the pro-Lighting to Type-C cable or the decryption chip in the camera case is pirated, it is recommended to buy it again.
The profit is meager, and the above two lines are not standard, you need to buy them separately. Only one standard computer cable is connected.

4. Insufficient hanging gear and have to mention
1). Smart power-on and power-off, plug in the USB DAC, U1 will automatically power on, the indicator light is on the knob, and the power will be turned off automatically when the cable is pulled out.
2). Automatically turn off the high-voltage op amp power in 5 minutes at minimum volume, automatically shut down at 20 minutes in minimum volume, and automatically restore when volume is increased
3). Low battery automatic shutdown
4). The physical relay is silent, without any electronic switch
5). All aluminum handle knob is good, the main control ADC acquisition knob is then CNC AK4493EQ volume, completely solve the knob bias problem.
6). The main body has no pattern, users can play it at will.
7). 12 hours + battery life

(Translated using Google Translation.)

Gallery
~ PCB front Side


~ PCB rear Side


~ PCB w/ battery


~ Top


~ Bottom


~ Side


~ Block diagram


Links:
∆ You can get the ZiShan U1 here:
https://m.tb.cn/h.VO0RhDa?sm=dbacc7 (priced at $34)
∆ Amanero driver link (A):
https://www.amanero.com/drivers.htm
∆ DSD setting link (B):
https://pan.baidu.com/s/17WTwiTPi2u-PUbozKPgctA
Extraction code: n055
∆ Android software link (C):
https://pan.baidu.com/s/1IWEaVzzjQA52NEBHMjGgUw
Extraction code: 2zpn

Updates:
None so far.

NOTE:
I haven't order this unit yet so can't give you any more informations. As always any critics/suggestions are always welcome. What do you guys think about this new DAC+AMP from ZiShan? For me, i think it's interesting.

Lastly, this thread is created for everyone and aimed at sharing opinions, reviews, mods, and and other stuff about the ZiShan U1. Please keep it peace, friendly and an easy-to-read discussion thread. So let's use this thread as best as possible. Thank you

Stay healthy,
God bless.

Nice specs. I may looking for an amp for my Foxtex 610

 

[IcedFrosty]

Is there alot stuff to change? I am good with soldering iron, but would not know what to change in an amp but would not mind modifying my U1 if I would know what to change

Once my U1 arrived, i will share the pics in closer shot to make it clearer for those who loves solder/resoldering.

Would love to discuss hardware modding with ya!

Nice specs. I may looking for an amp for my Foxtex 610

Well this is not a standalone headphone amplifier. You need to connect the U1 digitally and then you can use it as DAC+Amp for your TH610. I'm sure it's powerful enough to drive those wooden beauty

 

[BubisUK]

Recieved mine today. Did not have time to play with it, but tried to connect it to tempotec and it did not work will try to play with settings tomorrow when I will have time.

 

[IcedFrosty]

Recieved mine today. Did not have time to play with it, but tried to connect it to tempotec and it did not work will try to play with settings tomorrow when I will have time.

Cool. Your U1 arrived so fast. Mine's still in the air according to AE. Well i have to be patient, like really patient.

Anyway, why would you connect it to tempotec though?

Well play with it if you got time. And share what you got