1 (edited by Misterpops 2022-01-06 23:11:14)

Topic: Digital noise from USB

Hi,

I’m conducting a lot of tests with my UCX.  When My PC is off, I can’t hear any noise from my Yamaha HS8 monitors.  If I use my Axe FX in the card (connected XLR in the 2 preamps on the front) it’s still noiseless.  It works just fine.

As soon as I start my PC, I can hear noise, kind of digital coming from the right speaker.  On the left it’s less obvious. My PC is a 2018 HP Omen desktop and I made sure there’s no power saving enable.  I tried  also with an Alienware Laptop and was getting the same problem.  As soon as USB is on on the PC, we hear the high pitch digital sound.  If I shutdown the PC, the noise disappear.  The UCX can still route its input to the monitor and it works like a charm.  It’s not a groundloop noise....it’s really related to the USB.   What can I do ?

I am using the PSU that is coming in the box.  If I wasn't powered by the official external power supply then how could I confirm that it works fine when the PC is OFF.

There is something coming on the USB connector when I power on the PC that is generating something I can hear in my monitors...

Re: Digital noise from USB

99% of the time what you are hearing is power supply noise that gets in via the ground line. I have one usb interface that is very sensitive to it, an old Mbox  and of all the laptops I tried one is dead silent (maybe like 5 tried). Even on battery they are noisy except this one. So I think also the power regulators on the motherboard play a role.
What you can try first is disable al C states for the cpu in the bios. Most of the time not possible on a laptop.
What should help is a usb isolator, but you do need a external power supply for the UCX then. Search this forum for usb isolator

Vincent, Amsterdam
https://soundcloud.com/thesecretworld
Babyface pro fs, HDSP9652+ADI-8AE, HDSP9632

3

Re: Digital noise from USB

The UCX does not use USB bus power, so using a power supply is mandatory (and included).

Regards
Matthias Carstens
RME

4 (edited by Timur 2020-01-16 12:19:30)

Re: Digital noise from USB

The noise originates from several components that interact with each other. Most notorious are dedicated graphic-cards, mainboard VRM (voltage section) and power-supply. What makes things more difficult is the interaction of these components. It is said to be possible to cancel noise from the GPU by using a different power-supply (platform, not just "manufacturer"). This is because resonance frequencies can build up between the components (like PWM of the PSU resonating with the VRM of the GPU). I am about to test this with a newly ordered PSU that is supposed to help with NVidia RTX cards.

Anyway, said noise travels from the various ground connections via USB and XLR cable shielding to your powered Yamaha HS8 speakers, which in turn close a loop via earth/protective ground (three prong power-plug). In order to get rid of it you need to cut the shield at one point. I prefer to break pin 1 (shield) of the XLR cable at the speakers' side. If you own several audio interfaces you could also break the connection by using an optical connection in between (like USC->USB->UCX->optical->Babyface->Yamahas). There are also USB isolators that serve this function (for more money spent).

https://forum.rme-audio.de/viewtopic.php?id=29907

You could also try to switch power-sockets for your display and other PC connected devices that use 3 prong power-plugs. This changes the travel path for the noise over the various ground lines and can thus lead to cancellation (or amplification) of said noise.

Re: Digital noise from USB

I just upgraded from my trusty Fireface 800 to the UFX+ and am also being dogged by terrible computer noise that would seem comes from USB ground issues. I've tried changing power outlets to no avail and half my monitoring goes to passive speakers/amp via RCA so I can't simply break XLR ground pins in hopes to remedy this. Can anyone weigh in as to successes they have had with these issues? I'd love some feedback before I drop huge money in USB filtering or power line cleaners in a vain attempt to troubleshoot or worse yet try to return the UFX+ and go back to my old Firewire interface.

6 (edited by Misterpops 2022-01-06 23:15:24)

Re: Digital noise from USB

Topic: Digital noise from USB
Hi,

I’m conducting a lot of tests with my UCX.  When My PC is off, I can’t hear any noise from my Yamaha HS8 monitors.  If I use my Axe FX in the card (connected XLR in the 2 preamps on the front) it’s still noiseless.  It works just fine.

As soon as I start my PC, I can hear noise, kind of digital coming from the right speaker.  On the left it’s less obvious. My PC is a 2018 HP Omen desktop and I made sure there’s no power saving enable.  I tried  also with an Alienware Laptop and was getting the same problem.  As soon as USB is on on the PC, we hear the high pitch digital sound.  If I shutdown the PC, the noise disappear.  The UCX can still route its input to the monitor and it works like a charm.  It’s not a groundloop noise....it’s really related to the USB.   What can I do ?

I am using the PSU that is coming in the box.  If I wasn't powered by the official external power supply then how could I confirm that it works fine when the PC is OFF.

There is something coming on the USB connector when I power on the PC that is generating something I can hear in my monitors...

I tried a couple of audioquest Jitterbug alike (USB adapter) without success.

Re: Digital noise from USB

Just a note that resolved most of my USB noise issues buy purchasing a dedicated USB 3 audiophile PCIe card for my system. This seemed to remove the RME UFX+ from the motherboard's noisy sockets.

Re: Digital noise from USB

Thanks for the PCIe USB port suggestion.  Unfortunately,  I don’t have a spare PCIe slot on my board.

Just wondering if something like a ifi iGalvanic3.0 could solve my issue by removing the physical connection between the PC and my RME UCX.  Or any suggestion that could remove that USB noise.  I would chnge the USB cable for one with ferrite rings….

If anybody has suggestions!!!  It would be welcome !

Cheers !

9

Re: Digital noise from USB

https://hifimediy.com/product/intona-hi … or-7055-c/

https://www.amazon.de/2-0-Hi-Speed-Isol … 01N8129OU/

Regards
Matthias Carstens
RME

Re: Digital noise from USB

Yesterday I have tried Topping HS-01 isolator with ADI-2 DAC and UCXII and both devices work with it. I did not have ground problem before and from the sound point of view I also did not noticed any change to better.

One strange thing - HS-01 becomes relatively hot after a while.

So I have measured current and it takes via input USB connector from PC:
0.24 A when just connected to usb with no other device,
0.38 A when only external power is connected - more ??????
0.42 A when ext. power + usb headphones connected ????
0.34 A when no power, only usb headphones
So it takes more power when only ext.power is connected then when no ext. and only headphones connected. I don't understand it.
By the way those headphones were not detected by OS, only DACs worked. Also wireless mouse receiver did not worked with HS-01.

With other noname Chinese isolator for 1/10 price both mouse and usb headset worked, but both RME DACs did not worked.
This isolator takes :
0.06 A with usb headset connected
0.01 A with no device connected.

ADI-2 DAC, Digiface USB, Fireface UCXII, ARC USB, Neumann MA1 aligned monitors