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dragonspit4

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My Topping DX7s is shipping to me right now, but I have a grounding problem with my computer.
In fact, I have a terrible noise problem.

Do I need to buy IFI Idefender 3.0 and IFI iPower?

(Amirm said that a good DAC with proper design, should filter out all USB noise problem, do I still need to buy ISO Regen, or IFI iGalvanic?
 
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dragonspit4

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You don't need them and you won't solve your grounding problem even if you used them.

What is the grounding problem right now?

Thank you for replying.
I have extremely high noise floor (when I turn my volume to max.) (like a continuous hum)
Also if I use max volume, when I move my mouse I can hear beepppppppp---------------- and if I stop my mouse, the noise stop.
 

amirm

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Those are problems that should vanish with external DAC that you have bought. The internal DACs pick up noise easily from surrounding circuits. External ones are far away from them and at any rate, have much, much better design.

Let us know how it works out.

And oh, I have a couple of these filters to test. :)
 
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dragonspit4

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Those are problems that should vanish with external DAC that you have bought. The internal DACs pick up noise easily from surrounding circuits. External ones are far away from them and at any rate, have much, much better design.

Let us know how it works out.

And oh, I have a couple of these filters to test. :)

Currently my am using Computer USB ---->ODAC Rev B ----> schiit Lyr 3
I know that all the noise I am having is from my USB port. (ODAC Rev B is powered entirely from USB power)

Wouldn't Topping DX7s be in the same situation as ODAC? (since Topping DX7s DAC portion is powered by USB?)
 
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dragonspit4

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Ah, I thought you were using internal DAC. Yes, there could be the same issue but best to wait until you get it and see.
My Topping DX7s will coming 1-4 days (soon). If this DAC ends up with noise issues (since it's usb powered) and I have to buy Idefender, Ipower and ISO Regen just to correct the noise issue, I will be so mad. Why spend $500 dollars for this expensive DAC, if I need additional noise filter.
 

graz_lag

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My Topping DX7s will coming 1-4 days (soon). If this DAC ends up with noise issues (since it's usb powered) and I have to buy Idefender, Ipower and ISO Regen just to correct the noise issue, I will be so mad. Why spend $500 dollars for this expensive DAC, if I need additional noise filter.

Hmm ... Just a second : the DX7s is designed with it's built-in PSU. What do you mean for "since it's usb powered" ?
 

KR8NUX

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Hmm ... Just a second : the DX7s is designed with it's built-in PSU. What do you mean for "since it's usb powered" ?
Exactly, he's right. If you use optical spdif and it has its own power brick, where is your claim coming from ? The only problem then would be if your home's electrical wiring has a grounding issue.
 
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dragonspit4

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amirm

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There is no galvanic isolation in any of these DACs. So the moment you connect a USB cable to them, you will experience potential ground loop issues. This is the reason I am a fan of balanced interconnects.
 

amirm

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My Topping DX7s will coming 1-4 days (soon). If this DAC ends up with noise issues (since it's usb powered) and I have to buy Idefender, Ipower and ISO Regen just to correct the noise issue, I will be so mad. Why spend $500 dollars for this expensive DAC, if I need additional noise filter.
None of these will remedy your issue if you have it. Some actually make the problem worse because they have their own power supplies and create more mains leakage! The ifi iPower, Regen, etc. all have this issue. They also don't filter anything that is useful to filter.

But again, get your unit and let's see where you stand.
 

Headphonaholic

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Currently my am using Computer USB ---->ODAC Rev B ----> schiit Lyr 3
Sure you don't have a bad tube? If you can, try changing to a different tube.

**EDIT** Sorry, I just realized that you said you have beeping sounds when moving the mouse. A bad tube might be responsible for some of your noise but you definitely have something interesting going on. I've had an issue with an SSD causing noise before, it was super bizarre and I didn't know what it was until I read that others had the issue.
 
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dragonspit4

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There is no galvanic isolation in any of these DACs. So the moment you connect a USB cable to them, you will experience potential ground loop issues. This is the reason I am a fan of balanced interconnects.
Thanks for reply again!
From your statement, it means that even with internally powered DAC with linear power supply inside of the DAC (not usb powered DAC), it might still have potential ground loop issues (generate hum noise) the moment you connect USB cable to it?
 

amirm

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Correct. Some people have had success removing power from USB cable by making their own or buying one that way.

99% of the time this is not an issue though. Ground loops are always there but they need to rise up to a level that makes them audible
 
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dragonspit4

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Correct. Some people have had success removing power from USB cable by making their own or buying one that way.

99% of the time this is not an issue though. Ground loops are always there but they need to rise up to a level that makes them audible

So even if I return my topping DX7s and get a internally powered DAC such as SMSL SU-8, I will still have a group loop issue, if my issue is there?
 

amirm

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So even if I return my topping DX7s and get a internally powered DAC such as SMSL SU-8, I will still have a group loop issue, if my issue is there?
It is a random thing so no way to predict it. But again, vast majority of time this is not a problem. So don't be too anxious about it. :)

If you get SMSL SU-8 and pair it with a balanced amp input, then you have more of an insurance here.
 
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dragonspit4

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It is a random thing so no way to predict it. But again, vast majority of time this is not a problem. So don't be too anxious about it. :)

If you get SMSL SU-8 and pair it with a balanced amp input, then you have more of an insurance here.

My current system: (Note: ODAC Rev B is usb-powered DAC)
Computer back IO panel ----> Cheap USB Cable ----> ODAC Rev B ----> Cheap RCA Cable ----> Schiit Lyr 3

My DX7s shipping is delayed due to labor strike in Canada, it will arrive next Monday or Tuesday (3-4 more days), but since I am so afraid that I will have the same ground loop issue as my original DAC. I went out and bought idefender and iPower just in case. (I am going to return them if they don't work.)


===== Here is the testing Results: =====

Original:
Computer back IO panel ----> Cheap USB Cable ----> ODAC Rev B ----> Cheap RCA Cable ----> Schiit Lyr 3

Result:
Max volume on Lyr 3 using low Gain: observed static and hum noise (very clearly audible), when I move my mouse, a high pitch beep sound occurs
Max volume on Lyr 3 using high Gain: observed heavy static and heavy hum noise (very loud), when I move my mouse, a loud high pitch beep sound occurs

Conclusion:
Observed static and hum noise (very clearly audible).

With iDefender Only:
Computer back IO panel ----> iDefender----> Cheap USB Cable ----> ODAC Rev B ----> Cheap RCA Cable ----> Schiit Lyr 3

Result:
Max volume on Lyr 3 using low Gain: observed static and hum noise (very clearly audible), when I move my mouse, a high pitch beep sound occurs
Max volume on Lyr 3 using high Gain: observed heavy static and heavy hum noise (very loud), when I move my mouse, a loud high pitch beep sound occurs

Conclusion:
Absolutely no change whatsoever compared to Original setup.

With iDefender + iPower:
Computer back IO panel ----> iDefender + iPower ----> Cheap USB Cable ----> ODAC Rev B ----> Cheap RCA Cable ----> Schiit Lyr 3

Result:
Max volume on Lyr 3 using low Gain: No audible noise, no noise when moving mouse
Max volume on Lyr 3 using high Gain: No audible noise, no noise when moving mouse

Conclusion:
Audible noise is completely killed. There is no magic here. iDefender is useless by itself. iDefender + iPower combo just replace the usb power from computer power supply to a cleaner 5V power.

Note:
My DX7s will arrive in 3-4 days, I will test it with and without the iDefender + iPower combo and see if there is any difference. (For science!!!!!!!!)
@amirm thanks for trying to help me, but I am still very very very anxious about it, I ABSOLUTELY don't want to use iPower and iDefender at all, but if the noise is still there even with DX7s, then.... I will.....................................be sooo mad!
 

graz_lag

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Correct. Some people have had success removing power from USB cable by making their own or buying one that way.

99% of the time this is not an issue though. Ground loops are always there but they need to rise up to a level that makes them audible

I am part of the other side of the moon aliens o_O who had made their's DAC powered by a battery, by means of a Y USB cable.
Deep musical improvement ? I do not know, or better, I do not thing TBVH, just happy to have get rid of the potential issue ... :cool:
 
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