Audio-GD Master 9
Sep 8, 2021 at 8:03 PM Post #1,832 of 2,699
I am resident in Australia and currently considering purchasing a MASTER 19 direct from the manufacturer, as I do not know of any sellers in Australia.

The majority of reviews and posts appear to imply the musical ability of the MASTER 19 is very good, but I have also seen posts nominating reliability issues with their Audio-Gd equipment.

If purchased I would be using the MASTER 19 with a Mirus Pro DAC and a ME850 Speaker Amplifier, but have yet to purchase any headphones.

I would appreciate any constructive advice on the above to help me evaluate if the MASTER 19 would be a worthwhile purchase.
I've had their Flagship DAC and Balanced Amp Combo, not sure what the model was called now.

I have been a huge fan of Audio GD products from a long time.
You will not have any issues with reliability and Kingwa is great support.
As for the Sonic Signature, in my opinion their equipment is fairly analytical.
 
Sep 19, 2021 at 12:41 AM Post #1,835 of 2,699
Greetings,

I wonder if any experts here can help me determine the faulty piece in my setup. It's been narrowed down to either the HE1 or HE9. I don't want to send one back to Kingwa and then he tells me nothing is wrong then I have to pay for both-ways shipping.

My issue is a very small audio glitch/pop that occurs in the left channel of my speakers, lasting maybe 1ms, very short very quiet, not in the audio source as it cannot be reproduced when winding back the track and not everyone can hear it when they don't know what it sounds like. Once you hear it and know what it sounds like, you can't unhear it. I have worked with Kingwa to try to figure this out over the past year and as far as we can tell the fault is on either the HE1 or HE9. The way we narrowed down to these two were by changing cables, reversing left/right cables on different gears, I even swapped my speakers (top enclosures only).

As part of the diagnosis, Kingwa had me remove the shorting jumpers in the HE9 (strangely the left channel on the HE9 had a missing jumper). This did eliminate the pop as far as I can tell or at least greatly reduced it, I possibly still hear a few pops here and there over very long periods of listening (i.e. 8 hours or more), but infrequent enough for me not to care - much. Kingwa says the jumpers in the HE9 was interferring with the R7HE, which makes me question whether the HE1 is faulty since the HE9 isn't directly connected to the DAC, Kingwa seems to think the issue is related to the HE9.

The pop happens in a very specific scenario: ACSS > HE1, with HE9 switched on (with or without shorting jumpers) and only with moderately complex music. It cannot be heard using XLR output into the HE9, I also tried connecting HE1 to Master 2H via XLR and it cannot be heard either. There is also no pops with HE9 acting as pre when the HE1 disconnected, Kingwa says this doesn't necessarily mean the HE1 is faulty, because the HE9 is far less transparent than the HE1 so I may not hear the pop, which is true as the pop is of a lesser magnitude than other details which the HE1 reveals.

Another thing that could be of clue, is that sometimes when I am piping music out to my speakers and I switch off the HE9, the R7HE will stop outputting any audio until it is restarted. If connected via USB, my PC can still see the R7HE (Amanero), it simply won't output any music, from any source, regardless of input. This happens rarely but enough times for me to know it isn't a coincidence.

Here's my setup:


1632023881571.png
 
Sep 19, 2021 at 8:20 AM Post #1,836 of 2,699
I would agree with Kingwa that a problem device is HE9. Missing jumper is suspicious, perhaps somebody removed it on the channel that was giving a problem. It doesn't look like a coincidence. However a root problem is with ground loops between HE9 and PC. It is a reason why firmware on the Amanero module hangs (requiring a power cycle). It could be a leaky transformer in the HE9 or just reversed live and neutral wires on the power cable. Check all power cords with multimeter if all are wired the same. I have one moulded (factory made) cable with reversed wires. Do you power all equipment from the same outlet? If not, please post details.

I may have a solution with using a custom XLR cable on the HE9 connection. Before I post details, I'd like to ask, what happen when you plug a streamer directly to the R-7HE and a PC though DI-20HE? I think it is better overall, as usually PC is a bigger source of ground loops than a streamer.

Bottom of line, DI-20HE should have two USB ports.
 
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Sep 20, 2021 at 12:50 AM Post #1,838 of 2,699
@PeterCraig

You mentioned you have an he6 se.

Do you have the m19 or m9? What level volume do you need to drive the he6?
 
Sep 20, 2021 at 8:11 AM Post #1,839 of 2,699
@PeterCraig

You mentioned you have an he6 se.

Do you have the m19 or m9? What level volume do you need to drive the he6?

Hi, I have the M19. The average recording is very loud at 55-60 volume level using high gain.

Due to the exponential volume control power goes up quite rapidly after that and at 70+ would likely cause hearing damage.

The slam is really impressive, I'm still breaking in the HE6se and really enjoying it.

M8Svol1.jpeg
 
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Sep 26, 2021 at 6:54 AM Post #1,840 of 2,699
I would agree with Kingwa that a problem device is HE9. Missing jumper is suspicious, perhaps somebody removed it on the channel that was giving a problem. It doesn't look like a coincidence. However a root problem is with ground loops between HE9 and PC. It is a reason why firmware on the Amanero module hangs (requiring a power cycle). It could be a leaky transformer in the HE9 or just reversed live and neutral wires on the power cable. Check all power cords with multimeter if all are wired the same. I have one moulded (factory made) cable with reversed wires. Do you power all equipment from the same outlet? If not, please post details.

I may have a solution with using a custom XLR cable on the HE9 connection. Before I post details, I'd like to ask, what happen when you plug a streamer directly to the R-7HE and a PC though DI-20HE? I think it is better overall, as usually PC is a bigger source of ground loops than a streamer.

Bottom of line, DI-20HE should have two USB ports.

Hey been meaning to thank you for your response, and also find time to listen (been quite busy these days). I haven't tested the power cables yet, it's a lot of work but I have done the USB cable switch as you suggested, i.e. Streamer connected to DAC and PC connected to DI-20HE and HE9 turned on. I spent yesterday listening with the PC to DI-20HE and today with my streamer directly to R7HE and the sound was flawless from both, no glitch and no "maybe" glitches. Did you expect this? What does it mean?

Also, I checked my power connections. Everything is connected on the same circuit. The difference is my PC and HE9 are connected to the same power socket, and the rest of my gear is connected to a different power socket about 3.5m apart.
 
Sep 26, 2021 at 5:38 PM Post #1,841 of 2,699
I spent yesterday listening with the PC to DI-20HE and today with my streamer directly to R7HE and the sound was flawless from both, no glitch and no "maybe" glitches. Did you expect this? What does it mean?

Also, I checked my power connections. Everything is connected on the same circuit. The difference is my PC and HE9 are connected to the same power socket, and the rest of my gear is connected to a different power socket about 3.5m apart.
Glad is solved now. A clue is there.
Another thing that could be of clue, is that sometimes when I am piping music out to my speakers and I switch off the HE9, the R7HE will stop outputting any audio until it is restarted. If connected via USB, my PC can still see the R7HE (Amanero), it simply won't output any music, from any source, regardless of input.
HE-1 is on the path and ACSS connection is unlikely to transfer noise, so a conclusion was that there had to be a direct interaction between HE-9 and R-7HE. Now we know that PC and HE-9 are plugged to the same power outlet, but different than R-7HE. This is what cause hanging Amanero firmware. This socket can be on a different fuse, all fuses are these days electromagnetic switches, not a good situation.

It seems there is nothing wrong with your gear. Using DI-20 with isolated USB port solves a problem, but I still suggest to use extension cord to power PC and HE-9 from the same power outlet.
 
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Sep 27, 2021 at 4:41 AM Post #1,842 of 2,699
Glad is solved now. A clue is there.

HE-1 is on the path and ACSS connection is unlikely to transfer noise, so a conclusion was that there had to be a direct interaction between HE-9 and R-7HE. Now we know that PC and HE-9 are plugged to the same power outlet, but different than R-7HE. This is what cause hanging Amanero firmware. This socket can be on a different fuse, all fuses are these days electromagnetic switches, not a good situation.

It seems there is nothing wrong with your gear. Using DI-20 with isolated USB port solves a problem, but I still suggest to use extension cord to power PC and HE-9 from the same power outlet.
Wow you just solved something with 2 posts that Kingwa and I couldn't figure out in a year :) do you think an USB isolator will do the same? Like the ifi iDefender? Or I can try unplugging the USB from my PC when I listen, that should also help right?
 
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Sep 27, 2021 at 6:26 AM Post #1,843 of 2,699
Wow you just solved something with 2 posts that Kingwa and I couldn't figure out in a year :) do you think an USB isolator will do the same? Like the ifi iDefender? Or I can try unplugging the USB from my PC when I listen, that should also help right?
Did you tell Kingwa everything? A language barrier is a big problem in practice. Some people accuse me of being offensive, but it is not my intention. I can either try to be polite or to pass the essence, I didn't acquire skills to do both in the same time.

Yes, you can try iDefender, it does a job redirecting ground loops. To make it effective, you need external power supply. It is not effective to a level that galvanic isolator does. There is more universal device for the same price, try this. What you really need to do is to get a 3.5m power extension, problem solved...

I don't know what you mean 'unplugging'. When you unplug, music stops. :)
 
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Sep 27, 2021 at 5:17 PM Post #1,844 of 2,699
Did you tell Kingwa everything? A language barrier is a big problem in practice. Some people accuse me of being offensive, but it is not my intention. I can either try to be polite or to pass the essence, I didn't acquire skills to do both in the same time.

Yes, you can try iDefender, it does a job redirecting ground loops. To make it effective, you need external power supply. It is not effective to a level that galvanic isolator does. There is more universal device for the same price, try this. What you really need to do is to get a 3.5m power extension, problem solved...

I don't know what you mean 'unplugging'. When you unplug, music stops. :)

Let's just say I have a logistical issue plugging both my PC and HE9 into the same socket as my HE1, it's actually easier and cheaper for me to get the device you linked.
By unplugging I meant to unplug my PC from the DAC. When I listen to music, I use the streamer to DI-20HE connection. If the ground loop is with the PC USB, the cheapest (but inconvenient) solution should be simply unplugging my PC's USB right? Thinking about this, maybe a USB switch would work too?

Something like this: https://www.ebay.com.au/itm/333671377404
 
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Sep 27, 2021 at 6:14 PM Post #1,845 of 2,699
By unplugging I meant to unplug my PC from the DAC. When I listen to music, I use the streamer to DI-20HE connection. If the ground loop is with the PC USB, the cheapest (but inconvenient) solution should be simply unplugging my PC's USB right? Thinking about this, maybe a USB switch would work too?

Something like this: https://www.ebay.com.au/itm/333671377404
That's correct.. And a port switch should work, but I do actually like configuration that started to work without problems. Streamer to a DAC and PC to DI-20HE. In next step would be to get streamer working as an endpoint to the player running on PC, so everything goes through the streamer over a LAN. No need to walk around to press a button. Less connections, less ground loops
 

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