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VGuitar Central => Tutorials and Demos => Topic started by: jon_bondy on February 23, 2008, 11:08:22 AM

Title: Solve USB Audio Noise when USB cable is connected
Post by: jon_bondy on February 23, 2008, 11:08:22 AM
I just tried my dream setup: VG-99 connected to a laptop via USB using the Editor and with the guitar outputs connected to my amp (as I usually do).  The amp was overwhelmed with electronic noise.  When I pulled the USB cable, the noise went away.  This was true whether the VG was powered or not, and whether the Editor was running or not.  It seems as if the laptop is injecting noise into the VG via the USB cable.

Anyone else have this problem?  Is it a defect in the laptop (which other wise is old but works fine).  Puzzling.

:)

Jon
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on February 23, 2008, 11:18:56 AM
http://www.soundonsound.com/sos/nov04/articles/computerproblems.htm (http://www.soundonsound.com/sos/nov04/articles/computerproblems.htm)
(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fmedia.soundonsound.com%2Fsos%2Fnov04%2Fimages%2Fcpstudioinstall.l.jpg&hash=a39d4667e7298aecd4e706d16eb889a5abb125d2)

Classic problem using Unbalanced 1/4" connected Audio Gear in a big Rig with some laptops and the new switching power brick supplies used everywhere today-

Typically one item in your rig (the Amplifier)  is already tied to Earth ground. The Unbalanced 1/4" Sleeve connection on all the  Audio Gear Audio Cable Shields feed this Common Ground to the Roland/Boss processor, and the USB Cable Shield feeds this same  Ground reference to the Laptop  - so technically All gear is still actually Grounded to the Earth. 

But if your laptop employs a Three prong AC Power cord with Earth Ground- your Computer will have a Ground Loop between the AC power cord and the USB Cable Shield. Remember most Windows laptops are Not designed for Audio, and its very common for a Windows laptop to introduce high pitch noise into all your audio signals - this is from the Laptop Power supply.


I had the same problem - but i found a solution.

To debug -

Reconnect all your gear as you like - keep the USB connected to laptop - but try unplugging the Power supply from the Laptop Computer. If the high pitch noise goes away - you found the problem ( its a ground loop from the Laptop's Power supply)

(yea - I know its high frequency "HISSSSSS" you are trying to cure - not 50/60 cycle Ground hum!)


Solution #1  - Run your laptop on its own Battery

Solution #2  - Obtain an Ebtech Hum-X - which filters noise on the AC Ground connection
http://www.ebtechaudio.com/humxdes.html (http://www.ebtechaudio.com/humxdes.html)
(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fwww.ebtechaudio.com%2Fhumxsplashbanner.jpg&hash=40ff4758b683481b588ce8145e56a07a65b73044)

Solution #3  -  A local  trip to hardware store for a ground lift adapter on the laptop's power supply AC three prong plug-

(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fwww.snapagogo.com%2Fuploads%2Fsource%2F282015%2F1422542705_955405506_ZZAC32.JPG&hash=d25e473df9f1b9303adfc81f631f0678825c639a)
http://www.adorama.com/ZZAC32.html?sid=1203794455588409 (http://www.adorama.com/ZZAC32.html?sid=1203794455588409)

Solved my noise on my HP/Acer/Lenovo Laptops

( and this explains why Macbook Pros use 2 prong AC Power adapters  = lower audio noise and no "switching noise" invading the audio
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jon_bondy on February 23, 2008, 11:53:54 AM
I now have all three devices (VG, laptop, and amp) powered from the same power strip.  The problem remains.  If I run the laptop on batteries, the problem goes away, so ti is power supply (switching) noise being injected into the laptop chassis.

You're advocating removing the ground connection for the laptop?  I'm not too worried about that, since the entire device seems to be made of plastic.

Tried using an extension cord that had the ground cut out: solved the problem.

Thanks!

:)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on February 23, 2008, 11:56:50 AM
Another happy customer:)


QuoteYou're advocating removing the ground connection for the laptop?  I'm not too worried about that, since the entire device seems to be made of plastic.

Actually the Laptop remains grounded via the USB cable to your audio interface inside your the Roland/Boss / Line-6 processor

I cant tell you how many times I have tried to explain the above  solution to people, only to have 3 days of debates from armchair "audio gurus" telling me:
"hogwash - Its Not a ground loop problem!"


Also check that your AMP does have the three prong AC grounded plug -

The Audio cables between the VG-99 and the AMP are providing the ground, the USB cable is grounding the laptop.


Be sure to ground your guitar strings too:

Many people forget to make a critical  connection when using the GK-2A, GK-3

Always Connect the short cable between your Strat's normal output and the  GK-2A Input - its makes the required string ground connection to the GK-2A.
ftp://ftp.roland.co.uk/ProductSupport/manuals/GK-3_OM.pdf

See page 18

"Normal
Guitar Cable
* This connection is necessary not only for playing the
guitar's normal (straight) sound as well as the
guitar's straight sound mixed with the synthesizer
sound, but also for connecting the guitar's ground
and the GK-3's ground. Even if you are not going to
use the guitar's straight sound at all, always make
this connection because of the noise reduction
benefits it provides."

If I remove this short cable - yea I have noise too - it goes away when I reconnect the short 1/4" cable (supplied with the GK-3) between my guitar and the GK-3
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Billy Kaffadrin on February 28, 2008, 12:28:39 PM

QuoteI cant tell you how many times I have tried to explain the above  solution to people, only to have 3 days of debates from "audio gurus" telling me "hogwash - Its Not a ground loop problem!"

Also check that your AMP does have the three prong AC grounded plug -

The Audio cables between the VG-99 and the AMP are providing the ground, the USB cable is grounding the laptop.  >>>

     
     Yeah a single ground is quiet, two or more ground points and you have a noisy feedback loop - but a point of caution; NO ground at all might be somewhat quiet  - AND it might kill you.  Typical example is the live gig and a guitar amp with a two prong only connection, and the guy touches a microphone and gets knocked out.  The amp is looking for a path to ground, the PA is grounded, and when the guy touches the mic his body becomes a conduit for the charge. Could happen touching the bass player too, if the Bass amp is properly grounded.  A practical solution if an amp is only two prong, attach a DI between the guitar amp input and an unused channel in the microphone snake.   That creates a path to ground for the ungrounded amp setup, so you doesn't have to be it.

     Sometimes equipment in a rack will ground through their chassis, and you get noise that is hard to track down that way.  But if you lift the grounds on all your gear, it's dangerous.  Good idea to have an outlet phase/ground checker in your bag for checking outlets you plug into on gigs too.

Billy

Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on February 28, 2008, 12:42:23 PM
GOOD ADVICE BILLY


I always use one of these
http://www.amazon.com/Electrical-Receptacle-Outlet-Ground-Tester/dp/B0012DHVQ0 (http://www.amazon.com/Electrical-Receptacle-Outlet-Ground-Tester/dp/B0012DHVQ0)
(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fecx.images-amazon.com%2Fimages%2FI%2F41k0DfHOl6L.jpg&hash=e9265f19b3aa7bb8ceffe850718896f1b59d6a58)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: s0c9 on February 29, 2008, 08:43:08 PM
Quote from: Billy Kaffadrin on February 28, 2008, 12:28:39 PM
     Sometimes equipment in a rack will ground through their chassis, and you get noise that is hard to track down that way.  But if you lift the grounds on all your gear, it's dangerous.  Good idea to have an outlet phase/ground checker in your bag for checking outlets you plug into on gigs too.

I can't STRESS how important it is to ensure that your equipment is properly grounded when playing live.
Not doing so CAN KILL YOU !!
It really ticks me off when some kid shows up with a new amp with a 2-prong power cable.

Like Billy says, ground noise is sometimes hard to track but is [most] often caused by equipment powered by different outlets on separate circuits -- especially in older buildings. These circuits often do NOT share a common ground [you think this would not be the case] and this causes the buzz. 
As a [small] independent SR [Sound Reinforcement] operator, we mostly run the PA for our own band, but do rent to others - hence have liablity potential.  Power at venues is a constant issue..... finding enough circuits to power 5 power amps [tri-amp sytem with 4 monitor mixes] + backline + lights is quite a challenge.  4000w FOH, 1800w of Monitors. We can run the system off 2 * 15-amp circuits [in a bar], but we prefer 3 or more to be available.

We use a version of the "poor man's power distro" [google it!] where the amp rack is powered by two 15 [or 20] amp circuits. Since all amps in the rack are metal and touch each other, this creates a common ground across both circuits. So no noise !!  We usually run a separate feed to the backline amps from the circuit with the lightest amp load. Anything connected to that [with a 3-pin] is automatically part of the "common" ground. Again no noise.
We also run power to the FOH console off another circuit [or 2nd] and power the rest of the backline off that too. One of the backline is powerd 1/2 from one circuit, half from the other, so that ties your whole system to a common ground - from keys to guitars to bass to mics and power amps.  Our system is VERY quiet.

It takes time to set this up and can co$t some $$ to make happen. Make sure your power distro shares grounds BETWEEN [ACROSS?] your EQUIPMENT and do not assume the venue is adequately grounded.  In 3 yrs we have not had a single complaint of someone having their lips "tingle" when touching their mic.

If THAT tingling does occur, you have a grounding problem, and its a sure sign of impending DANGER !!  Have folks down guitars, etc and power down their gear until you find it and fix it. 
DO NOT LIFT THE GROUND ON ANY GEAR TO RESOLVE THIS.  IT is EXTREMELY DANGEROUS.

Keep in mind that when you run a PA system at volume, you are running up to a 30+ amp load for your average bar gig. Between sets, that drops off to nothing... merely milliamps. If that 30+ amps suddenly decides to find its way to ground thru you mid song... Adios amigo. Need I say more... ??

Large systems are [20,000+ crowd] usually not prone to this as they often have their own gennies and electricians. Bars, clubs, halls etc, are often VERY badly wired... I urge CAUTION. Buy a $6 circuit/ground tester @ Lowes/Home Depot. It may save your life.

Sorry to ramble, but I've seen people get hit by ground faults and it is NOT pretty. After reading Billy's comments, I felt some clarification was in order..

-Steve
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on February 29, 2008, 08:54:14 PM
Good advice!



I always use one of these
http://www.amazon.com/Electrical-Receptacle-Outlet-Ground-Tester/dp/B0012DHVQ0 (http://www.amazon.com/Electrical-Receptacle-Outlet-Ground-Tester/dp/B0012DHVQ0)
(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fecx.images-amazon.com%2Fimages%2FI%2F41k0DfHOl6L.jpg&hash=e9265f19b3aa7bb8ceffe850718896f1b59d6a58)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Billy Kaffadrin on March 02, 2008, 03:24:26 PM
Quote from: s0c9 on February 29, 2008, 08:43:08 PM
Sorry to ramble, but I've seen people get hit by ground faults and it is NOT pretty. After reading Billy's comments, I felt some clarification was in order..

-Steve

    Well, the phasing of electrical outlets and the availability of dedicated audio power with a single ground reference are issues beyond the control of most guys doing small-medium size gigs.  But the idea of "Star Grounding"/a single ground point is a practical thing to get in people's minds regarding troubleshooting their individual rigs I think.  Certainly when the audio guy tells you not to use *that* power outlet though, use *this* one, people should do it.

    But even with dedicated audio power, when faced with an amp with a two prong plug or worse also having a two prong plug on their European 220 to 120 volt inverter for their pedalboard/amp rig, you have got to ground the setup somehow.  The DI solution is easier than running a ground wire from the amp chassis to the stage monitor mixer's chassis, and you can't just let guys kill themselves on your watch...

Billy

Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: truth57 on April 29, 2008, 02:17:23 AM
I have an Acer Aspire laptop, and with this computer, this problem seems quite severe. Also, being a European model bought in Spain it does not have a three pin plug, and generally the older houses like mine do not have an earth wired into the circuit. So I am not sure how to go about implementing the recommendations that have been made here in earlier posts.

It is definitely the laptop's power supply that is the problem, as even with the VG-99 connected to the USB port of my desktop which is in no way connected to my laptop (other than by wireless, but not as a network) if the audio out of the VG-99 is connected to the audio in of the laptop the same noise is generated and goes away when the adaptor is disconnected from the laptop.

Due to the lack of available 64 Bit drivers I cannot use the Acer laptop either to edit the VG-99 or record direct from it via USB, but I have decided to try a solution.....

I found a Phonics mixer with a Firewire connection (Phonix Helix 12 Firewire MKII) that is claimed to have full support for Windows Vista 64 Bit OS, and that will hopefully allow streaming of 10 channels of audio into my laptop and its software applications for DAW. This will hopefully also allow me to monitor and mix the other instruments in my home studio setup, although very basic (in addition to the VG-99, just a VG-8EX, an EMU Proteus 2000, a Midiman Midisport 4x4 and various VST plugin instruments), as well as allow me to solve the EQ disparity problem I am presently experiencing when trying to use the VG-99 in a live situation.

As many others have stated, there really is a big difference in EQ between sounds mixed through headphones and the subsequent sound when heard through a PA system, even though everything is absolutely flat on the mixer in terms of EQ; everything sounds way too thin, and requires radical re-EQ'ing within the patches themselves.

I have decided to do away with my power amp and purchase a pair of powered reference monitors, in the hope that their flat response will help me to correctly adjust the EQ for live use. However I suspect that there is in fact a disparity between the EQ of the headphone outs and the mix outs of the VG-99, which would account for the problems many of us have been experiencing. As you can tell, I have very little knowledge and understanding in this field, but am hoping bit by bit to acquire the necessary information to enable me to work successfully with the system.

Thanks,

David
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: sixeight on April 29, 2008, 05:39:20 AM
You definately need a properly grounded power outlet if you want to do anything with a computer and recording sound. I also have a house without properly grounded outlets, but I have taken the trouble to get a properly grounded outlet close to my computer. Without it, i would not be able to get a "clean" recording of a distorted guitar (distortion makes noise and hums worse).
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: truth57 on April 29, 2008, 08:44:57 AM
Quote from: sixeight on April 29, 2008, 05:39:20 AM
You definately need a properly grounded power outlet if you want to do anything with a computer and recording sound. I also have a house without properly grounded outlets, but I have taken the trouble to get a properly grounded outlet close to my computer. Without it, i would not be able to get a "clean" recording of a distorted guitar (distortion makes noise and hums worse).

Thanks Sixeight, I am in the process of trying to sell the house, so it is not worthwhile investing in such a rewiring/grounding project, but I am going to make sure that my next property choice will be more modern and suitable to my home studio. But in the meantime this noise is driving me nuts  ;D.

The laptop itself seems to make no such noise unless the VG-99 is plugged into it (or connected to my desktop), and what makes it even worse is the USB connection as already mentioned. So it looks as though I am going to have to do my sound designing monitoring directly into my headphones, and that should solve the problem.

However I had hoped to be able to do all my editing and recording using my far more powerful laptop, but unless I am able to successfully install Windows XP on the SATA drives, that is not going to be possible.

David
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: truth57 on April 29, 2008, 08:19:03 PM
In the interim I managed to get a version of XP Pro to run within Vista 64 Bit in VMware. I now have the VG-99 connected to my laptop via USB and notice that it makes far less noise than it did when connected to my desktop PC. I have no idea why, because the last time I tried connecting it to the USB port of my laptop it produced far more noise, yet now it is relatively quiet, even without removing the power supply from the laptop.

There is no separate ring main to separate wall sockets from lighting circuits here, so it might be that the noise is worse when the refrigerator is running or something similar. I certainly noticed that this made a big difference while trying to run DAW applications with my desktop PC.

I also believe that there must be some sort of earth loop problem with the wiring from the desktop PC. So this has been a step in the right direction.

David
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: beatpete on May 11, 2008, 09:58:00 AM
I had the same problem with my Phonic Helix 24 firewire board. Lifting the ground on the laptop completely cured the problem. As far as safety goes, the entire system is STILL grounded via the Phonic board and the connected audio/firewire cables. I assume that this would be the same with the VG-99 EXCEPT that it uses a DC power suppply and I'm not sure if that supplies adequate ground. If there's a grounded amp in the equation, then I think lifting the grounds from everything except the amp would work AND be safe. Basically, you want to avoid ground LOOPS and I think this gets really noticeable when using a computer.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: truth57 on May 12, 2008, 01:28:11 AM
Quote from: beatpete on May 11, 2008, 09:58:00 AM
I had the same problem with my Phonic Helix 24 firewire board. Lifting the ground on the laptop completely cured the problem. As far as safety goes, the entire system is STILL grounded via the Phonic board and the connected audio/firewire cables. I assume that this would be the same with the VG-99 EXCEPT that it uses a DC power supply and I'm not sure if that supplies adequate ground. If there's a grounded amp in the equation, then I think lifting the grounds from everything except the amp would work AND be safe. Basically, you want to avoid ground LOOPS and I think this gets really noticeable when using a computer.

Thank you Pete. Incidentally I just received my Phonic Helix 12 board, so it will be interesting to see how it fares combined with my Vista 64 Bit laptop and the VG-99. The VG-99 itself has a ground lift switch, and I did try it without noticing any perceptible change. A friend of mine who also uses an Acer laptop had the same problem, but apparently solved it by wiggling about the connection in the DC adaptor. According to him the problem is especially noticeable in Acer laptops, but having little experience with other makes I cannot verify that. But what I can say is that when the VG-99 is plugged into the USB port of my desktop, the noise produced via the laptop (which is my monitoring source until I configure the Helix board) is increased substantially. It is digital noise too, with an audible digital clocking effect. I am really hoping that once I have everything running via the Helix board and the Firewire interface this will solve the problem, but it makes editing the VG-99 very difficult, because of that noise.

Thanks,

David
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on May 12, 2008, 08:03:01 AM
If you read my inital reply to this thread - you will find what is the cause of this digital white clocking noise - its due to the switching power supplys used on all the gear including the VG-99, and  the Laptop.

The VG-99 includes an actual Chrome Ground Screw to assist in grounding the VG-99 chassis.

In my use, I typically use the VG-99 with a Macbook Pro - never have noise issues.

I also have a HP ZD7000 Notebook - and with that machine I must use the ground lift adapter (see my earlier post) anytime I attach the VG-99 Output to an external GROUNDED  Power amplifier.

Observe - All gear has a Ground Path - the USB Cable is grounding the Laptop through the VG-99,   which is grounded to the Power Amp (through the VG-99 Output Cables) 

Employing ground loop isolation strategies solves the digital white clocking noise. The Power Amp has a good ground connection and the audio cable shields pass this "safety ground" to the VG-99. Even a USB cable has a Ground Shield and ground connection- this becomes the  ground reference for the Notebook via the VG-99. 

Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: truth57 on May 12, 2008, 09:48:01 AM
Quote from: sustainiac on May 12, 2008, 08:03:01 AM
If you read my inital reply to this thread - you will find what is the cause of this digital white clocking noise - its due to the switching power supplys used on all the gear including the VG-99, and  the Laptop.

The VG-99 includes an actual Chrome Ground Screw to assist in grounding the VG-99 chassis.

In my use, I typically use the VG-99 with a Macbook Pro - never have noise issues.

I also have a HP ZD7000 Notebook - and with that machine I must use the ground lift adapter (see my earlier post) anytime I attach the VG-99 Output to an external Power amplifier.

Employing ground loop isolation strategies solves the digital white clocking noise. The Power Amp has a good ground connection and the audio cable shields pass this "safety ground" to the VG-99. Even a USB cable has a Ground Shield and ground connection- this becomes the  ground reference for the Notebook via the VG-99. 


Thank you forgive me if I am having a hard time keeping track of the posts on these forums.....however there are two issues that set this setup apart, one is the lack of earth I already mentioned in the house, which is something I cannot change right now, and the second is that my VG-99 was connected to my desktop but still producing noise in the laptop because I am using its soundcard to monitor the output. That is an issue that should be resolved by using the Firewire card of my Phonics desk.
However I now have an issue with the drivers for the desk, Windows Vista refuses to allow me to use unsigned drivers and Phonic customer support inform me that this can be worked around within the user permissions of Windows Vista 64 Bit, but I've already tried everything and cannot find where I need to make the necessary changes in the system.

Regarding the ground lift on the VG-99, I bought mine from the UK, and the plug it comes with has a plastic replacement for the ground pin, so I very much doubt it has any effect whatsoever. In fact the plug itself consists of a 2 pin to 3 pin adaptor with a plastic 3rd (ground) pin. Seems pretty ridiculous to me...

Here in Spain, the newer plug sockets have a border in both the plug and socket that connects to the ground wire. The problem is that in older properties this is not the case and there is no actual ground wire in the house. That is the way of it here. Now I should mention that as my active monitors have still not arrived, I am presently continuing to use the cheap stereo tuner CD combo in order to take the outputs from the desk, and there is absolutely no noise via the desk itself. This is because the VG-99 output is going to the desk rather than to the laptop soundcard as before. So once the driver issue is resolved the ground loop problem should also be resolved.

I think the Phonic desk is excellent quality by the way, very clean and transparent. Can't wait to get the active reference monitors. The VG-99 through the sub outs sounds way too toppy, just the problem I have in rehearsals and when playing in church. But now I can hear the same thing here, so I can start to look for a solution.

Thank you for your help....

David
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on May 12, 2008, 10:30:57 AM
FWIW - In Many countries around the globe -  You can improvise a Earth connection by using the nearest Cold Water Pipe -

Its best to find where it enters the house ( and check that it is 100% Electrically Conductive metal!)

In the USA - the Telephone company always has a Ground Clamp located on the Cold Water Pipe -
(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fwww.structuretech1.com%2Fwp-content%2Fuploads%2F2010%2F01%2FGround-Clamp.jpg&hash=8980363f775d9e97d6851bbbb8a046ace81f82ec)

  - this IS the Earth Ground - and you could feed a 12 gauge wire to your studio room and call this "Ground".

http://www.hardwareandtools.com/invt/6439038?ref=gbase (http://www.hardwareandtools.com/invt/6439038?ref=gbase)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: truth57 on May 12, 2008, 11:14:21 AM
Quote from: sustainiac on May 12, 2008, 10:30:57 AM
FWIW - In any country around the globe -  You can improvise a Earth connection by using the nearest Cold Water Pipe -

Its best to find where it enters the house

In the USA - the Telephone company always has a Ground Clamp located there already.

  - this IS the Earth Ground - and you could feed a 12 gauge wire to your studio room and call this "Ground".

http://www.hardwareandtools.com/invt/6439038?ref=gbase

Thanks Steve, that sounds like a far better suggestion than ramming a steel rod into the ground, which is how it is done here  ??? The water mains is a plastic system, but where it enters the butane water heater the piping is copper, would this serve? There is also another cold water outlet to an external tap, could that be used?

Regards,

David
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on May 12, 2008, 12:07:26 PM
You will want to locate the actual Main Water entry for the House. This should be a metal Pipe.

Its best to FIRST check that it is 100% Electrically Conductive metal!)



Re: The Copper Cold Water Entry to the Water Heater - Be sure this Copper Cold Water Entry is emerging from the Ground - if "YES"  - install the Ground Clamp there.

If your Cold water supply pipe is Plastic - then DO NOT USE THIS CONNECTION.

BTW - they do use a very long Copper stake into the ground, if the Cold Water Entry is not available - or too far away from the Studio.
(https://upload.wikimedia.org/wikipedia/commons/thumb/7/7d/HomeEarthRodAustralia1.jpg/800px-HomeEarthRodAustralia1.jpg)
If you can locate a local HAM radio operator there in Spain - he should be able to help you with advice on the best local method of achieving Earth Ground connection for your Home Studio.   

https://en.wikipedia.org/wiki/Ground_(electricity)

https://www.erico.com/selectCountry.asp?returnURL=%252Fpart%252Easp%253Fpart%253D615880

https://www.erico.com/part.asp?part=615880

(https://www.erico.com/catalog/variants/PH36816m.jpg)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: MikeC on November 19, 2008, 01:05:46 PM
I've just spent an afternoon trying (sucessfully) to fix this very problem in my setup. I'm running a Desktop PPC Mac Dual 2Ghz, with a MOTU 828mkII and MTP AV for audio and MIDI interfaces. All my rack gear is powered from one well shielded and filtered mains extension block. My guitars, amps and VG99 are located about 20 feet away in a 'performance' area. All the performance gear was powered from a different shielded and filtered mains extension block. To reach the Mac USB ports, my VG99 and my POD X3 ran via an Active USB Extension. Both POD and VG99 gave out excessive noise including clock signal oscillation - POD was significantly noisier than VG99. Additionally, the VG99 was running through a powered hub before the Active Extender cable.

Today I experimented with re-cabling:
1) running the POD & VG99 from the Mac's power block - slightly less noise from the VG99, no change from the POD
2) running USB cable into a passive extender then into the Mac, cutting the powered hub out completely - complete lack of noise from the VG99, no change from the POD; the POD actually produced noise at a lower level even when it was powered down!
3) finally tried lifting the shielding on a USB cable - both devices worked, but no real change to the noise levels (though the VG99 became susceptible to USB cable handling noise)

I'm happy that I've cured the noise problem for the VG99 at least! (though I have to keep an eye on the USB cable running at ankle height into the front of the Mac!) ;D

MIke
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: MikeC on November 21, 2008, 07:58:26 AM
More good news. Just fitted a Sonnet Allegro USB 2.0 card into my Mac G5. Plugged the POD X3 in first and ... bliss! the noise was gone. Added the VG99 and still nothing. Now I can get back to the music!  :)

Mike
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: fokof on May 20, 2009, 10:52:58 PM
I had a nasty ground loop once on my "mobile" kit and the only way I got rid of it was by cuting the ground wire from  the USB cable (black). nothing else worked but that did the trick.

Maybe it can help someone.....
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jackyl666 on November 30, 2009, 09:01:35 PM
I have just started to use the VG-99 attached to my desktop and have a hum, tried cutting the black wire and had no luck still had the hum even louder now.

I have unplugged the computer figuring it was a ground loop, still have the hum. unplugged the VG-99 still there. unplug the cable between the two and it goes away. I am completely at a loss. It is not a terrible hum and probably not noticeable at normal levels but when I increase the line level on my mixer I start to hear it.

The ground lift on the VG-99 looks to only work on the balanced outputs from what I can see on the lines attached to the back of mine. Correct me if I am wrong, but it certainly looks like it on mine, either way it does nothing. 
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: baatkarlo on December 06, 2010, 01:40:29 PM
69 cents for a single cheater plug at Home Depot plugged between laptop power cord and socket resolved my ground loop problem. However, I then read the below link and am thinking of getting a DI at the main and sub out ports in the back of the VG-99.

http://bose.infopop.cc/eve/forums/a/tpc/f/6806048934/m/1171031006 (http://bose.infopop.cc/eve/forums/a/tpc/f/6806048934/m/1171031006)

My question is - how high is the risk ogf putting a cheater plug between laptop power plug and socket as compared to one between the amplifier's power cord and socket? The laptop does a step down conversion from 110v to 9v or something similar and pulls less curent, while an amplifier will often ste up to higher voltage and curent to drive speaker coils. 
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: headbush on April 08, 2012, 04:02:01 PM
Hey everybody!

I have a very annoying problem that makes GR-55 unusable for midi program changes through the USB!!! I've read few topics about hiss and hum coming out of the Guitar Out when connected to computer  via USB cable but my noise is like a generated high-pitched note around B on the 19th fret on the first guitar string... it is comming only from the guitar OUT and it gets really loud when I use the distortion in my chain after the Guitar Out. When I disconnect the USB cable - no noise at all!!! But I need to use the USB MIDI function! If someone knows anything about it , please help!!!

Thank you!!!
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gumtown on April 08, 2012, 04:38:06 PM
Ground loop problem, one option is to find a USB ground isolation device, or use the 5 pin midi ports of the GR-55, as they provide ground isolation.
Another solution is to isolate the guitar out with a D.I. box
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: headbush on April 10, 2012, 05:19:30 AM
Thank  you , gumtown!

I tried the DI solution but it seems it didn't change anything, I put the DI between the Sound card and the Amplifier and it just made things absolutely noise free - but when I use the USB Cable it's the same :)

I will check the USB Ground Isolation solution... that's really helpful
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: iamroberty on January 11, 2015, 10:12:18 PM
I picked up a GR-55 last week to use in my home recording studio and things are going fairly well so far, mostly thanks to this site, but I have run into a problem.  I am running the stereo line outs from the GR-55 to the stereo line ins on my line6 KB37 and it sounds great.  I have a midi-usb converter that I am using to send midi direct to my plugins in Ableton but when I plug in the GR-55s USB so I can play with patches in FloorBoard I can hear the high pitched data transfer of the USB coming through the line outs.  It goes away when I unplug the USB but I would like to be able to edit my patches during recording sessions.  Do I have to use the USB to connect to the GR-55 with FloorBoard or can I connect through my USB midi?  Does anyone else get this noise?  I swapped out my USB cable but it didn't seem to make a difference.  Is there any way to get it to go away?
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gumtown on January 12, 2015, 12:08:53 AM
The line outs and the USB together are causing a ground loop,
for minimal noise and no ground loop it is best to use the midi ports of the GR-55 for the GR-55FloorBoard editor,
it still works the same via midi.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: iamroberty on January 12, 2015, 03:39:20 PM
Thanks for the response!  I love your software.  So I am having an issue getting FloorBoard to connect to my gr55 without having it plugged into the usb.  I get an error every time that says "Midi: InMM: OpenPort error creating Windows MM MIDI output port."  Any advice?
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on January 12, 2015, 03:42:22 PM
QuoteI get an error every time that says "Midi: InMM: OpenPort error creating Windows MM MIDI output port."  Any advice?

That might be the default Windows Media MIDI/Ringtone soft player
Also occurs if you see "Microsoft GS Wavetable Synth" - Do not select that!
(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fwww.snapagogo.com%2Fuploads%2Fsource%2F112015%2F1421106351_544589928_GR55_FB_MIDI.PNG&hash=cdb9aef9a2b49b70d87775c53b398d4db9f75347)


You will need a  5 pin MIDI Hardware interface to connect to GR-55


Recommended USB <> MIDI 5 pin Interface cables are listed here:

https://www.vguitarforums.com/smf/index.php?topic=8393.0 (https://www.vguitarforums.com/smf/index.php?topic=8393.0)


Read more about Ground loop noise here:
https://www.vguitarforums.com/smf/index.php?topic=2078.0 (https://www.vguitarforums.com/smf/index.php?topic=2078.0)

10k HZ whine from the switching power supplies  employed in computers when a Ground Loop is present.

https://www.vguitarforums.com/smf/index.php?topic=12033.msg87222#msg87222 (https://www.vguitarforums.com/smf/index.php?topic=12033.msg87222#msg87222)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gumtown on January 12, 2015, 11:00:33 PM
Open the "Preferences > Midi/USB" menu and select the type of midi interface being used.
The GR-55 USB is also 'seen' as a midi interface device.
If a different USB port is used from the previous session, the midi device will need to be selected again as the GR-55 USB midi driver sees it as a different device (usually with a slightly different name with a 2 or 3 after 'GR-55' - typically a windows issue).

When you say the editor 'won't connect' without the GR-55 USB connected, I assume you are using another midi device adapter,
and that device is selected in the editor preferences menu.

HINT: the software selects the midi device from a list menu, not by name, but by the position number in the list.
If another midi device has been removed while in the same editor session, the software may lose connectivity.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Wallbagner123 on January 29, 2015, 06:37:49 AM
Hi there,
I been having a very similar problem when connecting the Usb cable from my laptop into my roland Br-800, i could hear all sorts of sounds comming from my laptop until i decided to unplug the power supply charging the laptop's battery.
So i decided to isolate the ground pin ( round Pin) from the ac power bar and  BINGO!!  no more interference, so i realized the the problem was comming from the lousy switching power supply of my laptop.

most laptop chargers have a 2 prong keyed plug, mine has a ground pin, so this is my 2 cents worth for you guy's , i thaught i'd share this .

Cheers
;)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on January 29, 2015, 06:43:36 AM
QuoteI been having a very similar problem when connecting the Usb cable from my laptop into my roland Br-800, i could hear all sorts of sounds comming from my laptop until i decided to unplug the power supply charging the laptop's battery.
So i decided to isolate the ground pin ( round Pin) from the ac power bar and  BINGO!!  no more interference, so i realized the the problem was comming from the lousy switching power supply of my laptop.

most laptop chargers have a 2 prong keyed plug, mine has a ground pin, so this is my 2 cents worth for you guy's , i thaught i'd share this .

I do the same

More details here
https://www.vguitarforums.com/smf/index.php?topic=367.msg1292#msg1292 (https://www.vguitarforums.com/smf/index.php?topic=367.msg1292#msg1292)


also

http://www.ebay.com/itm/like/161448039898?lpid=82&chn=ps (http://www.ebay.com/itm/like/161448039898?lpid=82&chn=ps)

(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fi.ebayimg.com%2F00%2Fs%2FNTAwWDUwMA%3D%3D%2Fz%2F9l8AAOSwF1dUOOgo%2F%24_35.JPG%3Fset_id%3D880000500F&hash=dd4ebbb91d71e11865bd06c11bad82b63daf527f)

Full speed USB 2.0 isolator with build in power transfer 2


and

http://andybrown.me.uk/2015/07/24/usb-filtering/

(https://www.vguitarforums.com/smf/proxy.php?request=http%3A%2F%2Fandybrown.me.uk%2Fwp-content%2Fimages%2F%2Fusbnoise%2Fschematic.png&hash=d824dc16f19e88c017444121bacbd8c567bb31a0)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on June 30, 2017, 12:30:16 PM
(https://www.computeraudiophile.com/uploads/monthly_2015_12/USB-Power_2_mt.jpg.fd0b2a37724a201dd2e2ce91c0743f69.jpg)
(https://thumbs.static-thomann.de/thumb/bdbmagic/pics/bdb/274226/9923371_800.jpg)

http://www.aqvox.de/usb-power_en.html

https://www.computeraudiophile.com/forums/topic/26127-usb-disruptor/?page=2

AQVOX USB Low-Noise Power Supply     (VAT policy for non EU countries >>)
https://www.thomannmusic.com/aqvox_usb_low_noise_power_supply.htm
Socket male/female USB Type-B,  USB Type-A, USB  3.0 Type-A

for USA/ Canada/ Japan/ Taiwan -  Mains Voltage 110-120V
including 120V to 220V AC step-up converter

Shipping costs for one unit to all countries is 17,00 EUR
(because of extra weight of the step-up converter shipping costs are 5 EUR more)

Attention! The power supply does not solve ground loop problems. Strong 50/60 Hz ground loup humm is not being eliminated.
The USB3.0 Type-A adaptor ist downward compatible wit USB2.0.
USB2.0 devices are fully functioning at the USB3.0 adaptor.

Input Voltage AC 140-260 V
Output Voltage DC 5 V/1 A

Fully compatible with all USB powered USB devices.



REVIEWS

• Review of AQVOX USB Low-Noise Power Supply: "gentlemanaudiophile.blogspot.de" (link opens new window)

• HiFi World UK: "Religious Conversion" (link opens new window)

• HiFi World UK: "USB-to-S/PDIF Convertors - Halide Bridge" (link opens new window)

• Audiocircle Online: "AQVOX USB Power Supply for DACs" (link opens new window)

• HD Fever France (link opens new window)



USB socket male/female: Type-B,  Type-A or USB 3.0 Type-A

The USB3.0 Type-A adaptor ist downward compatible wit USB2.0.
USB2.0 devices are fully functioning at the USB3.0 adaptor.

Compatibility List

NOT compatible
For the following devices our USB-power supply brings no sound improvement because the USB-chip is self powered (powered from the DAC itself)

Here the USB-chips are powered from the DAC´s internal powersupply. The 5V from the computer are not connected to the DAC, and as they are not connected, no "evil-computer-power" can affect or alter the USB-datalines or the DACs electronics. But AQVOX USB-cables will improve the DAC´s sonic performance.
We work on the incompatibility list...

Ayre QB9
Benchmark DAC1 new Generation
Arcus rDAC
Nortstar 192/24
Antelope Audio ZODIAC
T&A DAC8 - USB-Chip Tenor TE8802L is internally powered
Weiss
Arcam rDAC
Eastern Electric Mini Max & MiniMax DAC Plus
Musical Fidelity V - DAC II
Chord Qute HD
Audiolab 8200 CDQ and all other Audiolab devices with USB
Micromega myDAC
Wired4sound W4S DAC2 DSD


Compatible devices
USB-DACs , and other USB audio devices - this list is not complete, the market is simply to big.
100% compatible are all USB-devices without own powersupply.
But with many devices with external or integrated powersupply, the USB-chips inside are still powered from the computers USB-5 Volts.
!!! ALL USB-Devices without own power supply are GENERALLY compatible !!!

nearly all USB audio devices get a substancial sound improvement

Digital/Digital Converter - DDC - USB to SPDif (COAX/TOS/BNC)
AQVOX - myDDC 44.1-192/24 USB2 asynchr. with ASIO
AQVOX - myDDC SE (special edition) 44.1-192/24 USB2 asynchr. with ASIO
Anedio U2 SPDIF Converter
April Music Stello U2 24/96 USB Link
April Music Stello U3 24/192 USB Link
Audiophilleo 1 & 2
Bel Canto USB Link
Bel Canto mLink
Bel Canto uLink (NOT Bel Canto REFLink)
Berkeley Audio Designs Alpha USB
Bravo USB to S/PDIF Converter
Channel Islands Audio Transient MKII USB Converter (without 5V PS)
Firestone Audio SPDIF converter
HALIDE Design Bridge
Lindemann DDC - 192 + 96 USB
M2Tech - HiFace ONE und HiFace TWO 192/24 USB
Musical Fidelity V-link I & V-link II + V-Link 192 ( ja, wie alle voll USB-versorgten Geräte, kompatibel ! )
Resonessence Labs Concero
Sonicweld Diverter HR
SOtM dx-USB HD
Soulution 590 USB converter
Stahl-Tek A.B.C.
Wavelength Audio Wavelink HS
STELLO U2 + U3
Wyred 4 Sound µLink USB/Spdif converter
!!! ALL USB-Devices without own power supply are GENERALLY compatible !!!

nearly all USB audio devices get a substancial sound improvement

Digital to Analog Converters DACs + USB Audio Interfaces
AQVOX USB2DA MKI
AQVOX myMiniDAC 44.1-192/24 USB2 asynchr. with ASIO
AQVOX myMiniDAC SE (special edition) 44.1-192/24 USB2 asynchr. with ASIO
Abbingdon Music Research Digital Processor 777
Aesthetix Romulus Transport/ DAC
Aesthetix Pandora DAC
Anedio D2 DAC
Apogee Mini-DAC + DUET 2
APRIL Music Stello U3 192/24 USB LINK
April Music Eximus DP1
ATOLL DAC 100
Audionet ART G2 + G3 ( CD Player with USB input )
Audio Research ARC DAC & DAC 8
AURALiC ARK MX+ DAC ("ActiveUSB" - Custom AURALiC Drivers)
AURALiC Vega DSD DAC ("ActiveUSB" - Custom AURALiC Drivers)
AVID PRO TOOLS 9 +10 MBOX MINI
Bel Canto DACs USB Link
Bel Canto USB Link - versorgt vom USB-BUS
Bel Canto DAC 2.5 nur der USB-Chip wird vom Cpomputer versorgt
Benchmark DAC1 - erste USB Serien
Benchmark DAC2 HGC USB
Beresford USB DAC TC-7520
Bricasti Designs M1 USB DAC
Bryston BDA-1
Bryston BDA-2
Burson Audio DA-160
Burson Audio Conductor
Cakewalk UA-25EX CW USB Audio Interface
Calyx Femto DAC
Calyx DAC 24/192
Cambridge Audio DAC Magic
Cambridge Audio DAC Magic Plus
CEC DA53
Centrance USB Devices
Chord QBD76 (nicht Chord Cute HD)
dB Audio Labs Tranquility SE DAC
Devilsound DAC
Digidesign MBox 2 mini
Edirol UA1A USB Powered Audio Interface
E-MU 0204 + 0404
EMM Labs DAC2X
ESI Dr. DAC nano
Firestone Audio Fubar II + III
FOCUSRITE SAFFIRE 6 USB + SCARLETT 2I2
Hegel Hd2
HOTaudio Extasy USB DAC
HRT Music Streamer (all USB-Bus Powered Models) auch der HRT HD
IBUKI Musica USB DACs + AMPs
Jolida Glass FX DAC I / II / III
Jolida Fusion DAC / Transport
Kingrex USB DACs + AMPs
Korg DS-DAC-10
Lindemann DAC 24-192
Lindemann 825 HD Disc Player
Marantz NA7004 Network Audio Player/DAC
Matrix Audio X-Sabre DAC
Maverick Audio - DAC TubeMagic D1 & D2
M-Audio Fast Track USB & Fast Track C400 & C600
Meitner Audio MA-1 DAC
Meridian Explorer
Musical Fidelity V-DAC (Nicht der V-DAC II )
Musical Fidelity M1 DAC
NATIVE INSTRUMENTS KOMPLETE AUDIO 6 + TRAKTOR AUDIO 10
Northstar USB DAC 32 Essensio 192 etc.. viele USB Modelle
NuForce Icon 1+2 HD HDP uDAC-2/ uDAC2-HP
PRESONUS AUDIOBOX 22VSL + AUDIOBOX USB
Pro-ject USB Box
PROPELLERHEAD BALANCE
PS Audio DAC III
Resonessence Labs Herus DAC
REGA DAC
RME Babyface
Schiit BiFrost
Schiit USB USB-Geräte
Silverstone USB DAC
SimAudio Moon 300D
Sound Devices USB Pre 2
Slim Devices Squeeze Box
TEAC DAC H01
Logitech Squeeze Box Touch
TASCAM US 122L + 122 MKII + 144L + 144 MKII (all USB-Bus Powered Models)
Totaldac D1 REFERENCE D1 REFERENCE A1 USB http://www.totaldac.com/index.htm
Trends Audio DAC
Yellowtec PUC2

nearly all USB audio devices get a substancial sound improvement

!!! ALL USB-Devices without own power supply are GENERALLY compatible !!!
More examples of devices who gain performance with optimum USB-power quality
- external USB hard drives
- external CD/DVD drives
- Squeezebox Classic + Touch (sehr gute Klangverbesserung ! )
- ONKYO NDS1 iPod Dock
- CD-Players and Amps with USB input
- iPod - iPhone Docking stations
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: Elantric on October 06, 2017, 11:15:51 AM
https://youtu.be/ktEQVp2Iufk

https://youtu.be/jSA2F1AwboU
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on October 10, 2017, 12:22:42 PM
(https://hifimediy.com/image/cache/data/imguploader/IMG_5289-800x800.JPG)
A ) use a USB galvanic  Isolator that supports USB 2.0 @ 480mbps
https://hifimediy.com/high-speed-usb-isolator-480Mbps

v2.0 available now! We made some changes to support more DACs, as some DACs didn't work with v1.

The High-Speed isolator provides galvanic isolation between the USB host and device and protects the device from power shocks and avoid ground loops that can be very troublesome in audio. Our original Hifimediy USB Isolator has been very popular since it was launched in 2013, but the drawback is that it doesn't work with all USB devices. The new High-Speed Isolator works with many more devices and provides a long awaited solution to ground loop noises for users of sound cards like Focusrite, Steinberg and many more.

If you have tried our USB isolator in the past and found it wasn't compatible with your equipment, then there is a very good chance that the new High-Speed isolator will work. It supports all USB transfer modes, Low (1.5Mbps), Full (12Mbps) and Hi-speed (480Mbps). Hi-Speed 480Mbps are required by DACs that support higher than 96kHz/24bit sample rates, and also multi channel DACs.
The new isolator also provides more power, 400mA to the connected device, vs 200mA from the other USB isolator.


Specifications
Supports 1.1, 2.0, 3.0, 3.1 USB ports
Supports Low (1.5Mbps), Full (12Mbps) and Hi-speed (480Mbps) mode by automatic detection
Supports audio and other devices including high resolution 384kHz and DSD DACs, USB midi devices, USB mixers, USB microphones
Provides 400mA to connected USB device
No driver required, no settings to configure
Self powered, no external power needed
Signal isolation: 3000V
Voltage isolation: 1000V
Voltage Isolation 1kV
Size: 55x35mm + cable 10cm


FAQ

What is the difference from the cheaper USB isolator?
There are two main differences:

The new High-Speed isolator supports USB Hi-Speed 480Mbps mode, required by many audio devices.
it can provide double the power to your device (400mA vs 200mA).
Do I need the High-Speed isolator, or can I use the other cheaper one?
If you have a two channel DAC that supports not more than 96kHz/24bit then the non High-Speed one is likely to work if it doesn't require too much power. If it has mic preamp, phantom power or is a bigger type sound card then it might to require more than 200mA power and the High-Speed isolator is required.

Will the High-Speed isolator work with my audio or other USB device?
It probably will.

Does it require a driver or special setting?
No. Similar to a USB hub, the isolator is "transparent" to the computer and doesn't require any driver or configuration in settings.

Does it support USB 3.0 and 3.1?
Yes it works with USB 3.X ports. It will max out at 480Mbps, meaning if you connect a USB3.0 hard drive you will not get transfers at 5Gbps speeds. Audio devices doesn't need more than 480Mbps, so it will be sufficient. Most devices that require USB galvanic isolation doesn't require 5gbps.

Does it support asynchronous USB?
Yes it supports all USB types, the isolator doesn't care, it just passed on the data to your computer.

Will it improve the sound quality from my DAC?
It depends. If you are experiencing noise problems, then it will probably remove or reduce those if they are caused by a ground loop. The noise could also be caused by other factors, like the microphone or preamp itself (some gear are noisy!), the isolator will not help with that. It can also clear up the sound from ground issues that is not so apparent, creating a clearer background in the audio. If your computer has a good quality USB DC supply then the isolator might not further improve the sound quality. You're welcome to give it a try and send it back for a full refund if it doesn't help with your unique situation. You can also contact us if in doubt.

Will it fix the noise I'm getting from my sound card/microphone/midi keyboard/other device?
It will fix noises that are caused by ground loops, often presented as whining, buzz or loud shh noises. As long as the problem is not caused by the microphones/preamps itself (some microphones are noisy!) then it's very likely to fix the problem. You're welcome to give it a try and send it back for a full refund if it doesn't help with your unique situation.

Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on October 10, 2017, 12:26:38 PM
https://hifimediy.com/news/solving-noise-and-ground-loop-issues-with-usb-isolation
(https://hifimediy.com/image/data/adum4160.jpg)
Ground loops can be a problem when using USB audio devices. It generally happens when they are more than one ground path between two devices. This can result in hum, whining noises or artefacts. The ground shared with the computer is also often quite "dirty" as it is shared with the computers circuitry, processor and possibly also other devices in your house. It can be of great benefit to break the connection to the noisy ground and create a new separate ground.

This can be done with a usb isolation chip such as the adum4160 from Analog Devices.
This chip will create a new ground reference on the device side which will break any ground loop and remove the noisy ground.
The adum4160 chip is UL rated for 5000V isolation for 1 minute (UL 1577) and will also protect your devices from electrical shocks and damage from static electricity.

The device side needs to be powered separately. It can be done by supplying external power or power can be taken from the USB rail using a DC DC converter, as we have done with in our usb isolator. The DC is further smoothened with a LC filter.

(https://hifimediy.com/image/data/_MG_1905.jpeg)
https://hifimediy.com/usb-dac2

Our DAC 2 (UAE23+) includeds the adum4160 chip inside the device to have the DAC always isolated from USB hub ground. This DAC always needs to be supplied external power to function. The benefit of this is that a good quality  power supply can be connected and the USB power will not be used at all.

In listening tests the usb isolation have proven to significantly increase the sound quality to connected audio devices.

The usb isolation is "transparent" from the computer. You dont need any drivers or special settings on your computer for it to work. Just plug it in and connect your device.

Limitations
There is a couple of limitation you should be aware of. First, the adum4160 chip support USB "Full Speed" 12Mbps but not "High Speed" 480Mps. This means that DACs accepting up to 96/24 sample rates will work. However if you have a dac that support 192kHz (or higher) sample rates, then it will not work as USB "High speed" is required for anything above 96/24. Note - there is some confusion regarding the use of "USB 2.0" vs "High" and "Full" speeds. USB 2.0 refers to the standard (released in 2000) and supports both Low, Full and High speed. USB 3.0 (released April 2008) additionally supports "SuperSpeed" but still supports low, full and high transfer speeds. So even if your device says it supports USB 3.0 or 2.0 it will work if it runs on Full speed (12Mbps) which is the case for all dacs that support max 96/24.

Second, our usb isolator only provides 200mA of power to power your device. This is sufficient for many devices, but there are DACs and sound cards that will require closer to 500mA which is the max output a normal USB port can deliver. To give you an idea of power consumption we can inform that our Tiny dac requires only 30mA (!).

Adum4160 does accept both Low and Full speed devices, but a setting needs to be changed to select Low speed. Our usb device is factory set to support Full speed devices only, this means that low speed devices like USB mouse, keyboards will not work without modification.

With some computers it will no wake up from sleep by itself, meaning you have to unplug and plug it back in.
Tags: usb isolation ground loop noise


more
https://www.eevblog.com/forum/chat/high-speed-usb-isolator/
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on April 30, 2018, 11:37:38 AM
(https://encrypted-tbn1.gstatic.com/shopping?q=tbn:ANd9GcQuzrZu_zwHJNXJuKQHb4LxZPyOKvZUw_jE6z0EuJ1jLeYzqFI&usqp=CAY)
(https://encrypted-tbn1.gstatic.com/shopping?q=tbn:ANd9GcQ03eqtIjnoUNxh9iKZPSzSmiiQidTYBNWKLMlYbmc3dXT_ymZ7&usqp=CAY)
(https://encrypted-tbn3.gstatic.com/shopping?q=tbn:ANd9GcRdXkrHFBMIu8Jjetht7y_v2LisquJ8HJJ77M3_uya1_-p9Rmal&usqp=CAY)
(https://images-na.ssl-images-amazon.com/images/I/81ovMnZsjCL._SL1500_.jpg)

(https://www.stereo.net.au/forums/uploads/monthly_2017_03/IMG_20170323_1702171.thumb.jpg.6d6d04339077b17943da8f3c0bab7e63.jpg)

(https://www.stereo.net.au/forums/uploads/monthly_2017_03/IMG_20170323_1702484.thumb.jpg.1ec0835eebbd8c46a7a86bee41e75f9f.jpg)

iDefender3.0 USB Ground Loop Eliminator

Designed to Reduce Noise from USB Power, USB 3.0 Connectivity, Backward-Compatible with USB 2.0. Reduce the noise caused by USB ground loops with the iFi Audio iDefender3.0 USB Power Noise Suppressor. It is designed for use with DACs for breaking the ground connection while enabling normal handshake operation. It features a USB 3.0 input and output plus a micro-USB connector for connecting a 5 VDC power supply.

https://www.amazon.com/gp/product/B01N3XKOLG/ref=ox_sc_act_title_1?smid=A17MC6HOH9AVE6&psc=1



https://www.stereo.net.au/forums/topic/120486-fs-ifi-audio-usb-idefender30-usb-30-ground-loop-breaker/



--

https://support.saleae.com/hc/en-us/articles/208667616-Suggestions-for-Electrical-Isolation

Suggestions for Electrical Isolation
Avatar
Mark Garrison
Thursday at 12:34
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None of the Saleae devices electrically isolate the ground of the device under test from the host PC's USB ports. For most applications, this merely requires extra care from the user to prevent accidental ground loop short circuits. However, there are applications where electrical isolation between the device under test and the host PC is absolutely required.

In these cases, we recommend using some kind of electrical isolator. The seemingly easiest way to isolate the product is to isolate the USB connection. Unfortunately, almost all of the USB isolators currently on the market only support low-speed USB and full-speed USB. Our products require high-speed USB to operate. That is especially confusing because they are advertised as "USB 2.0 isolators"; however, USB high speed is not required to be considered USB 2.0.

There is one USB 2.0 high-speed isolator on the market:

http://intona.eu/en/products

We've tested it here, and it works very well. Unfortunately, there is one limitation. It can only provide 300mA of current to the downstream port, which is less than the standard 500mA from USB 2.0 ports. This is not a problem for Logic 4 or Logic 8; however, Logic Pro 8 and Logic Pro 16 will have problems. Logic Pro 8 may work with the LED turned off; however, Logic Pro 16 will not be able to function properly.

It may be possible to power the logic analyzer using a powered USB hub that is properly isolated. Most hubs include a 2-prong power supply that will provide some minimal isolation from MAINs earth ground, but they are generally not rated for isolation.

Our second recommendation is to simply isolate the digital inputs before they reach Logic. You may want to consider using this SI Labs digital isolator evaluation kit. Additional work will be required to get it running, and it won't work in all scenarios, but it's a good starting point.

http://www.digikey.com/product-detail/en/SI84XXISO-KIT/336-1765-ND/2170672

Unfortunately, we don't currently have any suggestions for analog input isolation. However, there is one other option you can consider.

You can also fully isolate the host PC and all other attached peripherals from other ground references. This is done most easily with a laptop running from battery power or by using a modified isolation transformer with its MAINS ground wire disconnected. Please note that we only mention this as a possibility and do not recommend it since it can put the operator in danger under some circumstances. If the operator becomes the ground short between the device under test and the MAINS ground (or another ground reference), serious injury may occur.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on April 30, 2018, 12:08:52 PM
https://hackaday.com/2017/03/09/wtf-are-ground-loops/
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on March 09, 2020, 01:28:25 PM
https://www.amazon.com/iFi-iDefender3-0-External-Ground-Eliminator/dp/B0849LVSZP/
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on June 27, 2021, 09:58:19 AM
This USB Isolator works to tame noise (ground loops via USB Data Cable)
https://www.vguitarforums.com/smf/index.php?topic=30581.msg224016#msg224016

https://www.amazon.com/HiLetgo-Channels-ADUM3160-Voltage-Isolator/dp/B07VK721RV/ref=pd_di_sccai_2/137-5800686-0809564

(https://images-na.ssl-images-amazon.com/images/I/61xG9Jd1FuL._AC_SL1100_.jpg)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on December 05, 2021, 09:47:39 AM
Solve USB mixer noise issue on Behringer USB Mixers  ,
(Lower Windows Mic Recording Gain
https://youtu.be/ZHZo8L3idLA
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on December 05, 2021, 09:49:06 AM
https://youtu.be/q2c6fKOu-vo
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on January 30, 2022, 07:22:01 AM
(https://audiophilereview.com/assets_c/2018/04/shaub82a-11566.html)

https://audiophilereview.com/cd-dac-digital/usb-cables-noise-and-galvanic-isolation/
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on March 23, 2022, 10:53:39 AM
I am running my electric guitar into stereo pedals into a Radial EXTC Reamp Box (but I am not reamping) and then into a UAD Apollo interface connected to a MacBook Pro 2019. The Apollo goes directly to the MacBook. Everything else, including all USBs, go into a CalDigit TS3 Plus dock connected to the Mac – which also charges the Mac. I am recording and monitoring in my DAW. With everything connected the background is dead quiet.
Some of the pedals have a computer app that connect via USB. When I load one of these apps in the MacBook I get all sorts of noise. If I unplug the USB cable the noise stops. This seems similar to the problems discussed above but I am not sure of the best solution for my situation? Would a simple USB "adapter" work? Is there one recommended and currently available? With the CalDigit TS3 involved and charging the Mac I am not sure how modifying any grounding would work. Any suggestions? Thank you.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gearhound22 on March 27, 2022, 10:59:14 PM
So looks like a few different solutions for the USB ground noise
USB ground isolator
Radial StageBug SB-6 Audio Isolator
Ebtech Hum Exterminator
All these are around the same price in Canada

I tried using a DI box with an isolator that solved my issue to prove that method....I'd prefer not messing with my raw guitar tone though.
The noise problem I'm having is from the Axon USB cable , if I pull the cable at either it or the axe-fx it stops.....its not hooked to a PC when the noise is present.

I noticed the other one in the thread is a high speed one....would this one work? Axon is only sending midi and used for editing.
https://hifimediy.com/product/usb-isolator/
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on March 28, 2022, 12:06:52 AM
Quote from: gearhound22 on March 27, 2022, 10:59:14 PM
So looks like a few different solutions for the USB ground noise
USB ground isolator
Radial StageBug SB-6 Audio Isolator
Ebtech Hum Exterminator
All these are around the same price in Canada

I tried using a DI box with an isolator that solved my issue to prove that method....I'd prefer not messing with my raw guitar tone though.
The noise problem I'm having is from the Axon USB cable , if I pull the cable at either it or the axe-fx it stops.....its not hooked to a PC when the noise is present.

I noticed the other one in the thread is a high speed one....would this one work? Axon is only sending midi and used for editing.
https://hifimediy.com/product/usb-isolator/

This USB Isolator works to tame noise (ground loops via USB Data Cable)
https://www.vguitarforums.com/smf/index.php?topic=30581.msg224016#msg224016

https://www.amazon.com/HiLetgo-Channels-ADUM3160-Voltage-Isolator/dp/B07VK721RV/ref=pd_di_sccai_2/137-5800686-0809564

(https://images-na.ssl-images-amazon.com/images/I/61xG9Jd1FuL._AC_SL1100_.jpg)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: TheOreoMonster on March 29, 2022, 09:19:25 AM
Similar set up to another mentioned here. Using A Boss GT-1000 with sub outs or main outs going to my interface. an Apogee element. The Apogee is connected directly to the Mac. The GT-1000 is connected with everything else usb to a Caldigit TS3+ Thunderbolt dock that also powers the Mac. It's noisy when the USB cabled is connected to the dock but dead quiet when it's not. It's  Also quiet if I connect the GT directly to the Mac but limited ports on this model means I can't have  the Apogee` and the GT connected directly to the Mac. I assume one of thes ground idolaters will be appropriate in this scenario as well?
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on March 29, 2022, 12:54:41 PM
Quote from: TheOreoMonster on March 29, 2022, 09:19:25 AM
Similar set up to another mentioned here. Using A Boss GT-1000 with sub outs or main outs going to my interface. an Apogee element. The Apogee is connected directly to the Mac. The GT-1000 is connected with everything else usb to a Caldigit TS3+ Thunderbolt dock that also powers the Mac. It's noisy when the USB cabled is connected to the dock but dead quiet when it's not. It's  Also quiet if I connect the GT directly to the Mac but limited ports on this model means I can't have  the Apogee` and the GT connected directly to the Mac. I assume one of thes ground idolaters will be appropriate in this scenario as well?

I own a few of these,  and solves many battles with noise
Radial Stagebug SB-6 Stereo isolation transformer box
(https://i.postimg.cc/ZKMrYv72/20220329-125151.jpg)

https://www.radialeng.com/product/stagebug-sb6
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: TheOreoMonster on March 29, 2022, 04:39:03 PM
Quote from: admin on March 29, 2022, 12:54:41 PM
I own a few of these,  and solves many battles with noise
Radial Stagebug SB-6 Stereo isolation transformer box
(https://i.postimg.cc/ZKMrYv72/20220329-125151.jpg)

https://www.radialeng.com/product/stagebug-sb6

I own a couple of the Ebtech Hum eliminator? would having that between the GT and the interface do the same thing? I assume thats where this radial device would be used? Cable out of GT sub out into EBTech Hum eliminator or Radial SB, then out of that device into the inputs on my  interface?

Thanks
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on March 29, 2022, 04:46:02 PM
Quote from: TheOreoMonster on March 29, 2022, 04:39:03 PM
I own a couple of the Ebtech Hum eliminator? would having that between the GT and the interface do the same thing? I assume thats where this radial device would be used? Cable out of GT sub out into EBTech Hum eliminator or Radial SB, then out of that device into the inputs on my  interface?

Thanks

Yes
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on March 31, 2022, 05:32:26 PM
Quote from: jm345 on March 23, 2022, 10:53:39 AM
I am running my electric guitar into stereo pedals into a Radial EXTC Reamp Box (but I am not reamping) and then into a UAD Apollo interface connected to a MacBook Pro 2019. The Apollo goes directly to the MacBook. Everything else, including all USBs, go into a CalDigit TS3 Plus dock connected to the Mac – which also charges the Mac. I am recording and monitoring in my DAW. With everything connected the background is dead quiet.
Some of the pedals have a computer app that connect via USB. When I load one of these apps in the MacBook I get all sorts of noise. If I unplug the USB cable the noise stops. This seems similar to the problems discussed above but I am not sure of the best solution for my situation? Would a simple USB "adapter" work? Is there one recommended and currently available? With the CalDigit TS3 involved and charging the Mac I am not sure how modifying any grounding would work. Any suggestions? Thank you.

To follow up, I ordered the USB module linked below and it solved the noise problem I was having using the computer software apps for my guitar pedals that connect via USB. Very happy!

https://www.amazon.com/HiLetgo-Channels-ADUM3160-Voltage-Isolator/dp/B07VK721RV/ref=pd_di_sccai_2/137-5800686-0809564
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gearhound22 on April 01, 2022, 02:34:28 AM
Quote from: jm345 on March 31, 2022, 05:32:26 PM
To follow up, I ordered the USB module linked below and it solved the noise problem I was having using the computer apps that connect to my pedals via USB. Very happy!

https://www.amazon.com/HiLetgo-Channels-ADUM3160-Voltage-Isolator/dp/B07VK721RV/ref=pd_di_sccai_2/137-5800686-0809564

Is it exposed or covered in heatshrink?

Odd its not in a case!!??
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on April 01, 2022, 05:37:20 AM
Quote from: gearhound22 on April 01, 2022, 02:34:28 AM
Is it exposed or covered in heatshrink?

Odd its not in a case!!??

It is just as it looks, exposed. So it does concern me a little. I might put it in a tube or box with the ends cut off. It is great that it can handle up to four USB connections. I have ordered another one to use in a different location.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on April 01, 2022, 07:04:01 AM
These are like Raspberry Pi. Intended for the DIY hobby crowd - easy to put it in a plastic box

Some just use large diameter heat shrink tube

But at $20 on Amzon it rivals the $200 alternatives which use same chips.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on April 05, 2022, 07:06:38 PM
Quote from: jm345 on March 31, 2022, 05:32:26 PM
To follow up, I ordered the USB module linked below and it solved the noise problem I was having using the computer software apps for my guitar pedals that connect via USB. Very happy!

https://www.amazon.com/HiLetgo-Channels-ADUM3160-Voltage-Isolator/dp/B07VK721RV/ref=pd_di_sccai_2/137-5800686-0809564

Another update. I have used the USB module successfully with the software programs for a couple of pedals. But I just tried it with Helix Edit with my Helix Stomp. Most interactions with the Stomp work but when I try to copy and paste a preset in Edit it crashes every time. If I remove the USB module copy and paste works fine. But I have the horrible noise back again. For some reason the USB module seems to have issues with some kinds of data transfer. Beware before you buy it. Would any of the other products mentioned not have this problem?
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gumtown on April 05, 2022, 09:19:42 PM
Probably this line in the sales description might give a clue:

Quote12 Mbps support USB 1.5 Mbps at low speed and full speed does not support pure high-speed equipment.

So the Helix data rate might exceed the device limitations,
maybe a more expensive and higher specification device will work.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on April 06, 2022, 06:50:30 AM
Quote from: gumtown on April 05, 2022, 09:19:42 PM
So the Helix data rate might exceed the device limitations,
maybe a more expensive and higher specification device will work.

Yes, that is what I suspect - that copy and pasting a preset in Helix Edit is too data intensive for that USB module. Unfortunately there aren't a lot of detailed specs for the software or hardware. And even if there were, I am not sure I would be able to interpret which specs would ensure full compatibility. So it seems a matter of trial and error.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: admin on April 06, 2022, 01:00:43 PM
$90
https://addictedtoaudio.com.au/products/ifi-idefender-usb-ground-isolator
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gumtown on April 06, 2022, 02:08:56 PM
Thinking about the Helix being USB connected through the isolator, if I recall the Helix also passes through multi channels of audio too,
so the data rate passed through will be quite near the high speed limits of USB 2.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on April 06, 2022, 05:56:02 PM
Quote from: admin on April 06, 2022, 01:00:43 PM
$90
https://addictedtoaudio.com.au/products/ifi-idefender-usb-ground-isolator

This one does says USB 3.0. I found it a little cheaper at Amazon. Worth a try. Thanks.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: TheOreoMonster on April 07, 2022, 05:42:49 AM
Quote from: admin on March 29, 2022, 04:46:02 PM
Yes
Thanks, using the Ebtech hum eliminator  definitely seemed to have resolved the issue here.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: gumtown on April 07, 2022, 12:51:33 PM
Cutting the USB ground wire is something I wouldn't risk, with the possibility of toasting my SY-1000 USB port.
It would leave the USB data pins open to static discharge when inserting the USB plug.
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: sixeight on April 09, 2022, 12:42:05 AM
Quote from: jm345 on April 01, 2022, 05:37:20 AM
It is just as it looks, exposed. So it does concern me a little. I might put it in a tube or box with the ends cut off. It is great that it can handle up to four USB connections. I have ordered another one to use in a different location.

I made a 3d printed enclosure for it.

(https://i.postimg.cc/YSqv3nqD/IMG_20210618_184547172.jpg)

Send me a pm if interested.

(https://i.postimg.cc/3xZy257D/IMG_20210618_184123514.jpg)
Title: Re: Solve USB Audio Noise when USB cable is connected
Post by: jm345 on April 19, 2022, 01:21:20 PM
Quote from: jm345 on April 06, 2022, 05:56:02 PM
This one does says USB 3.0. I found it a little cheaper at Amazon. Worth a try. Thanks.

Update on this USB device. The good news is that it allows data intensive actions in Helix Edit (like copy and paste presets) to transfer to the Helix Stomp, unlike the cheaper option I tried previously. The bad news is it did not reduce noise as well as the cheaper device. I had to use an optional USB power supply that plugs into the side of the USB stick to get any noise reduction. Unfortunately the noise reduction is not sufficient for my recording purposes. For now I will continue to use the cheaper USB device with Helix Edit and just make any data intensive changes directly on the Helix Stomp.