I no try it. Not the best option for reduced output impedance. Look at the Circuit Protection section on page 7 of the datasheet. + -30mA is recommended.

Yes. And there are people on player.ru who did this in Zishan.

I think when switching to bipolar power and removing electrolytic capacitors, the sound will become less colored and more like a sound from a line output.

In my Walnut V2, I reduced the output resistance. This really improves bass control even with 150 ohms headphones and increases the volume. If you just put the jumper instead of the resistors were distortion. With 10 Ohm, everything is fine, but you also need to increase the capacitance of the...

That is "away" from the opamp.

Frederick Wang, please take photos inside. I think many will be interested to see pcb :)

For reduce the brightness of "instruction" LED, you can try replacing R27 from 1.5 kΩ to 3-4.7 kΩ. I not try yet, but it must work.

It will only make it worse. In Walnut the "adapter" of 100 Ohm is already built in :D It is possible to reduce the output resistance by soldering in parallel R7/R8 other resistors. 100 Ohms in parallel will give a total resistance of 50 Ohms. 10 in the parallel ~ 9 Ohms. This increases the...

Copy from the terminal that you enter and output the program and paste here.

You can use ceramic capacitors of 10μF type X7R + 0.1μF type NP0 produced eg Murata. It is possible and more capacity of course :) Better before soldering to attach and listen to the noise in sensitive headphones with a minimum rotation of the potentiometer with different capacities.

https://goo.gl/AxCd48 The elder brother of Walnut?))) DAP/Amp/USB-DAC Zishan Z1. DAC ES9023 + opamp NE5532 with 12(18?)V power supply.

Thanks. 121 it's 12*10^1 = 120 Ohms, 1200 it's 120*10^0 = 120 Ohms too) In the intermediate version with the serial number, but still with the dip8 opamp, these resistors are 47 Ohms lol http://player.ru/showthread.php?t=183568&p=2163386&viewfull=1#post2163386

It's official support. But Walnut may read cards more capacity. On player.ru was info about 64-128Gb.

nick n, please see marking of R7 and R8 in your newest Walnut. I'm not sure but it seems there is 120 Ohms. This is a fragment of a photo of the renewed Walnut from taobao. Also R18 200kOhms not 240.

Why is there a second microusb?

This is the same potentiometer as in Walnut. My stock dead.. Black dots on inner ring.

Nutty potentiometer :) 5PCS/LOT 8pin RV097NS dual potentiometer B10K with switch audio / power amplifier / sealing potentiometer http://s.aliexpress.com/2QrEB367

LOL I can say to myself RTFM, because in the datasheets on the opamp there are recommendations for bypassing. For example, for lm6172, 0.01 μF ceramic and 2.2 μF tantalum capacitors are recommended from V+ and V- to GND. In our case, V- is GND, so you can simply increase their capacity.

it's 22uF

But bypassing opamp is more efficient :) I use in both places.

Also for better filtering of high-frequency noise from the power converter. I use ceramic x7r 22uF and MKT film 0.22uF.

You can reduce the output resistance. Solder the resistors eg 10 ohms parallel to R7/R8. The total resistance will be ~ 9 ohms. The volume will increase, the sound will become more flat, but the volume of the noise may also increase. Without changing the sound signature, you can only change the...

Article about upgrade potentiometer http://sound.whsites.net/project01.htm

I'm find really easy trick :o Resistors 1kOhm (1% precisely) should be soldered between the 2 and 3 contacts of the potentiometer. This emulates the logarithmic potentiometer. The sound adjustment became much more linear. It is easier to adjust the comfortable volume level.

You can replace the potentiometer by 50-100kΩ. This will extend the available volume range. for example http://mouser.com/ProductDetail/Bourns/PTR902-2015K-A104/?qs=sGAEpiMZZMtC25l1F4XBU1xwXnrUt%2fuoZmv44SKEpos=