[tienbasse]

   
I tried it with the 6P, worked well and sounded good.   For some reason, the XD-05 would always display 192 kHz when the N6P is connected.

Oh that's interesting, I have the same thing happening when connecting a Mojo to my LG V10 (Android 5.1.1), the Mojo always displays 192 kHz, while the display is correct when connected to a Meizu Pro 5 (Android 6).
Weird things happening, and I would suspect it has more to do with Android/the phone than with the DAC/amp.

 

[Phoniac]

   
Thanks, I am going to email them about it too.   By the way, in your post#734:
 
Was "sharp" a typo?   From what I read, slow is the one that has reduced pre and post ringing.  Sharp is the worse in terms of pre and post ringing.
 
https://www.ayre.com/pdf/Ayre_MP_White_Paper.pdf

 
No, not a typo but my personal opinion
 
I have no problem with a bit pre-ringing (short as it is here it is impossible to hear), but like that the post ringing is much shorter. IMHO. Each to his own...

 

[NGS11]

 
Oh that's interesting, I have the same thing happening when connecting a Mojo to my LG V10 (Android 5.1.1), the Mojo always displays 192 kHz, while the display is correct when connected to a Meizu Pro 5 (Android 6).
Weird things happening, and I would suspect it has more to do with Android/the phone than with the DAC/amp.

 
I also tried it on the Mojo and got the dark blue light so 192 kHz for sure.   Maybe the higher end phones and Android OS up convert to 192 when bit streaming.

 

[jamesbdh]

  Why no one takes photo of ground pins' connected area (need all black xd-05 but would be nice for comparison if you have silver xd-05)? Is the area scratched and scraped for connectivity?
 
There is ground issues in silver xd-05 in my opinion. I described this at my previous posts.
 
Ground pins: There are 3 ground pins(?) I saw. They are small golden pins and they are spring-supported. In silver xd-05; only 1 of 3 is ok. Others are connected to non conductive areas.

I would like to thank you I think.  I took mine(black) apart last night and saw the gold pins.  The case was scratched off and grounded but the two end plates were not.  I scratched off areas between the contacts and places were the case meets the end plates.  I used to have bad EMI from my phone.  It was not really an issue as I had a long cable and just moved it further away.  Today I placed my phone on top and I may have gotten a tiny bit but not like it was.  Obviously I cannot duplicate the EMI due to different towers, bands, and the weather, so I will continue to update.  I figured it wasn't a big risk to scratch off the paint on the inside. 
Update: so the EMI is still there but sitting with my phone directly on top with the aux cord wrapped underneath, gain on mid and as high as it goes with no music playing I can just faintly hear it some times. That could just be area I am in etc but seems to be an improvement.
 
Also for those that asked about getting the knob off, it is just a press fit.  I had to use a screwdriver to pry it off against the front plate. 

 

[fuzun]

 
I would like to thank you I think.  I took mine(black) apart last night and saw the gold pins.  The case was scratched off and grounded but the two end plates were not.  I scratched off areas between the contacts and places were the case meets the end plates.  I used to have bad EMI from my phone.  It was not really an issue as I had a long cable and just moved it further away.  Today I placed my phone on top and I may have gotten a tiny bit but not like it was.  Obviously I cannot duplicate the EMI due to different towers, bands, and the weather, so I will continue to update.  I figured it wasn't a big risk to scratch off the paint on the inside. 
Update: so the EMI is still there but sitting with my phone directly on top with the aux cord wrapped underneath, gain on mid and as high as it goes with no music playing I can just faintly hear it some times. That could just be area I am in etc but seems to be an improvement.
 
Also for those that asked about getting the knob off, it is just a press fit.  I had to use a screwdriver to pry it off against the front plate. 

Yes everyone should scratch if the assumption is correct.

 

[alpovs]

   
I tried it with the 6P, worked well and sounded good.   For some reason, the XD-05 would always display 192 kHz when the N6P is connected.

What was the Android version on your 6P and what cable did you use? USB-C OTG cables are hard to find. I am still not sure if the OTG concept even applies to USB-C. Android on my Nexus 5X is 7.1.1. I believe it is the latest stable. It was pushed early December. I am thinking the latest Android is to blame.

 

[NGS11]

 
What was the Android version on your 6P and what cable did you use? USB-C OTG cables are hard to find. I am still not sure if the OTG concept even applies to USB-C. Android on my Nexus 5X is 7.1.1. I believe it is the latest stable. It was pushed early December. I am thinking the latest Android is to blame.

 
My Nexus is running 7.1.1 so yours should work too.   You do need an OTG cable and they are readily available.
 
https://www.amazon.com/CableCreation-Female-Adapter-Macbook-Chromebook/dp/B0144GCXY6
 
https://www.amazon.com/dp/B018S827GU

 

[fuzun]

Good NEWS!
 
Today I scraped the ground of volume potentiometer's connected area (front case) and guess what; now it has less channel imbalance (not a significant difference) and also I can not hear audio at 0 level when gain is set 1 or 2. When gain set to 3 and knob is at zero; I can only hear thumps and it is so so quite. It is a bit quite now generally as well.
 
I did not test properly so this could be a brain effect but I strongly recommend you to try this. As it needed to be done before going out factory but they did not do this ( I do not know why. I think it is a stupid mistake ).
 
I am testing with shp9500.
 
Note that there is not a big difference but it made things better for sure!
 
If you want to do this there are 3 ground pins. 1 is already scraped out of the factory but 2 of 3 are useless as they contact to a non conductive area. We fix this by scraping related areas.
 
NOTE: If you are doing this do not scrape areas where it connects to other part of the case. If you do this (mistakenly) you may get some unwanted noise while listening in charge.
The best way is to making a dome-shaped hole where pins point. Do not alter other areas. Like I said if you mistakenly scratch (not even scrape) areas where two parts of the case connect, you may get unwanted noise while charging.

 

[fuzun]

And here is graph
 

 

[fuzun]

And the most clear improvement thing I have found is that now it does not leak sound. (I described this in my early posts)
 
I could hear the audio from xd-05 just like it is a speaker (lol it is real trust me. I recommend you to try before and after for this concern) when gain level set to 3 and volume at highest and imported audio is -10 db (In 5-10 centimeters). After the mod, I do not hear. I even tried putting my ear next to it and I still could not hear. Then I used equalizer and boosted audio level to near 0 db and then 10 dbs.
 
At 0 dbs (10 db boost); I heard the music but it was very quite and ear was next to it (0 cms).
At ~10dbs (20 db boost - Clipping to hell ; I heard the music when ear was next to it and heard noise at 3-5 cms.

 

[Holypal]

And the most clear improvement thing I have found is that now it does not leak sound. (I described this in my early posts)

I could hear the audio from xd-05 just like it is a speaker (lol it is real trust me. I recommend you to try before and after for this concern) when gain level set to 3 and volume at highest and imported audio is -10 db (In 5-10 centimeters). After the mod, I do not hear. I even tried putting my ear next to it and I still could not hear. Then I used equalizer and boosted audio level to near 0 db and then 10 dbs.

At 0 dbs (10 db boost); I heard the music but it was very quite and ear was next to it (0 cms).
At ~10dbs (20 db boost - Clipping to hell ; I heard the music when ear was next to it and heard noise at 3-5 cms.

Do you mean the mod reduces the noise floor a lot? In my XD-05, the noise floor is already quite good. I can hear some noise with highest gain and high volume. Do you mean this will disappear after the mod?

 

[fuzun]

Do you mean the mod reduces the noise floor a lot? In my XD-05, the noise floor is already quite good. I can hear some noise with highest gain and high volume. Do you mean this will disappear after the mod?

I don't think it is considered noise floor. I mean I could hear audio at highest settings possible if I do not connect headphones. Now I do not hear.
 
I think that you are referring to normal listening with headphones. I did not test this yet (sound quality) but I reported all of my findings I found.
 
But; theoretically, it should make sq better as ground was not set at all. This is a big big mistake.
 
 
If somebody can; we can test the finding if it is real or not with this method:
 
Open case, connect headphone and set volume at a moderate level then wear a not used high sensitivity and low impedance iem and touch its first pin to that ground pin. If you hear anything (left ear); it means that the sound (signal) you heard with iem gets reflected somehow, maybe a distortion to the connected headphone or leak directly as I described.
 
If you have bad ears and can not hear the leak at highest level without any headphone contacted; apply same method but set volume highest and do not connect a headphone to PHONE output. You will probably hear the sound at a very high level with the iem. I am saying that this is the leak.
 
Fixing leak does not make things much better as I could not hear the leak in real world situations. But; leak is not the only way that signal can escape. I am not sure but I am thinking that it can reflect to  PHONE output and this may make sound quality worse.
 
If this approach is correct, I can say that this mod will greatly make noise floor less. However; this is only an assumption.

 

[Holypal]

I don't think it is considered noise floor. I mean I could hear audio at highest settings possible if I do not connect headphones. Now I do not hear.

I think that you are referring to normal listening with headphones. I did not test this yet (sound quality) but I reported all of my findings I found.

But; theoretically, it should make sq better as ground was not set at all. This is a big big mistake.


If somebody can; we can test the finding if it is real or not with this method:

Open case, connect headphone and set volume at a moderate level then wear a not used high sensitivity and low impedance iem and touch its first pin to that ground pin. If you hear anything (left ear); it means that the sound (signal) you heard with iem gets reflected somehow, maybe a distortion to the connected headphone or leak directly as I described.

If you have bad ears and can not hear the leak at highest level without any headphone contacted; apply same method but set volume highest and do not connect a headphone to PHONE output. You will probably hear the sound at a very high level with the iem. I am saying that this is the leak.

Fixing leak does not make things much better as I could not hear the leak in real world situations. But; leak is not the only way that signal can escape. I am not sure but I am thinking that it can reflect to  PHONE output and this may make sound quality worse.

If this approach is correct, I can say that this mod will greatly make noise floor less. However; this is only an assumption.

Thank you very much. I'll open it and have a look tomorrow, when I have proper tools to do it. I'll let you know.

Btw, how do you scrape it? By knife or screwdriver?

 

[fuzun]

Thank you very much. I'll open it and have a look tomorrow, when I have proper tools to do it. I'll let you know.

Btw, how do you scrape it? By knife or screwdriver?

I collected some information and according to that;
 
*It does not matter if you have black or silver xd-05. At first I thought that black xd-05 must not affected from this issue because I thought that factory already know that black painted metal is not conductive so that they scraped black main body regardless of color. And they thought that silver back and front is not painted so they must be conductive. However;  they are not (anodized?). I honestly do not know why they only scraped the main body and not black back and front in black xd-05. [According to Hansolo, I can say that some or all black xd-05's ground is set up correctly. Read his comment:
 
I don't have any pictures of that from when I upgraded to my Burson V5i.  I can say that all the areas where the pins would make contact to the outer housing, in my black XD-05, the anodizing had been scraped off for a better contact point.  I noticed it on the front plate, back plate, and center housing piece.
 
I hope that helps. ]
 
 
This is the main point. We are doing a thing that xduoo factory supposed to do.
*2 of 3 grounds are not set up. Only charging ground is set up properly. You can scrape too it if you want but I don't think it will change any thing. But you can take it too just to use as an example for scraping.
*I just scraped with a screwdriver. There are a few things that you need to take care:
 
*The perfect scraping is *not scraping* but drilling. You can put a dome-shaped hole for the golden pin. Notice that it does not matter how much you scraped the area; the whole part except surface is conductive. Scraping like a rectangle or a planar way may lead to unwanted situations (Parts should not connect electrically! Refer to 3 below)
*If you use a screwdriver ; hold it like you hold a pencil. You do not want to break the glass at front panel.
*Put the inside(pcb) away. You only need back and front panel and if you want, the main case.
*When you are done,
1) You can test it with a multimeter. And with the method I described at previous post if you want to use your ear not a multimeter.
2) You need to carefully clean the surrounded area. There will be a lot of metal particles and if they get into the main board; you may end up with a short cut xd-05
3) Double check that you did not mistakenly scratch front; back and main cases connected areas. If they are scratched mutually cut small pieces of electric tape and put it to affected area.

 

[Holypal]

  I don't think it is considered noise floor. I mean I could hear audio at highest settings possible if I do not connect headphones. Now I do not hear.
 
I think that you are referring to normal listening with headphones. I did not test this yet (sound quality) but I reported all of my findings I found.
 
But; theoretically, it should make sq better as ground was not set at all. This is a big big mistake.
 
 
If somebody can; we can test the finding if it is real or not with this method:
 
Open case, connect headphone and set volume at a moderate level then wear a not used high sensitivity and low impedance iem and touch its first pin to that ground pin. If you hear anything (left ear); it means that the sound (signal) you heard with iem gets reflected somehow, maybe a distortion to the connected headphone or leak directly as I described.
 
If you have bad ears and can not hear the leak at highest level without any headphone contacted; apply same method but set volume highest and do not connect a headphone to PHONE output. You will probably hear the sound at a very high level with the iem. I am saying that this is the leak.
 
Fixing leak does not make things much better as I could not hear the leak in real world situations. But; leak is not the only way that signal can escape. I am not sure but I am thinking that it can reflect to  PHONE output and this may make sound quality worse.
 
If this approach is correct, I can say that this mod will greatly make noise floor less. However; this is only an assumption.

 
 
Hi, I just turned XD-05 on with highest gain and max volume. No headphone connected. I can't hear any leaking sound that you described.  I tried different songs.
 
What kind of leaking sound did you hear? The audio you played?