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Ground Loop / USB output noise
- Thread starter Smychavo
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spiritofjerry
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Those do not work for high speed USB devices.Get a proper USB Isolator like this
it will solve the problem and costs only <10$
JayGilb
Major Contributor
The iFi iDefender ground loop device claims usb3.0 compatibility, but is around $60 USD.
An its not an Isolator.
JayGilb
Major Contributor
Yes, it claims to break the ground loop by allowing a separate 5vdc supply to be plugged into the side of the dongle.
I have never used this unit and cannot attest to it's claims.
Using a separate supply is not the same as actually Isolating.
USB Data is still referenced to GND so you can’t completely brake ground or it wont work.
Therefore its not Isolated. Maybe helps a little bit because it increases impedance on the ground but its not Isolating
spiritofjerry
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I'm looking for a solution for a USB 2.0 device, a DAC/ADC that supports 192khz (for studio recording). Looks like the Intona is my best bet.
Looks Like the options for > a full speed USB 2 Isolator are very limited ;(
HiFime High Speed USB Isolator (hi-speed 480Mbps) Support low,full and hi-speeds
HiFime High Speed USB Isolator (hi-speed 480Mbps) Support low,full and hi-speeds
www.mrsazzadc.top
spiritofjerry
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Wait a second, is that the same as this? https://hifimediy.com/product/hifime-high-speed-usb-isolator/
If so, why is it so cheap on that website? Also, how would something like this product compare to something like the Intona line?
spiritofjerry
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Looking at it again, that website must be a scam. I've read elsewhere that they're in fact shipping the full speed isolators, not the high speed ones (which are out of stock on the reputable manufacturer's website).
Why is it so Expensive on the other website
Maybe its scam... but i have no idea would see if you can pay with paypal...
But i have no idea.
480Mbps is all you need for all audio interfaces i know. so if it arrives and works this can be a good solution
~70$ on aliexpress
https://de.aliexpress.com/item/1005001933476089.html
someone here from china said the are cheaper on TaoBao and apparently they work
spiritofjerry
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Because from what I understand, the actual chips and tech required for high speed isolation cost $$$.Why is it so Expensive on the other website
spiritofjerry
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Not a bad price, but there's no photos of the internals, so there's no guarantee these are using a topology that will fix the issue. Not to mention, no recourse if you receive the item and it doesn't work. Compare that small box to Intona's model, which has a visible circuit:
spiritofjerry
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I don't see an image
Got this from @Gouwa
According to him they work... looks isolated but i don't understand how it can work with this singel 3 pin device across the isolation
tvrgeek
Major Contributor
I found my cheap E-bay isolator and got the good Linear Tech isolator. Now, any suggestions to how to test?
I was thinking of generating a "perfect" 1K tone on the PC, then send it through the two isolators to various DACs, into my Focusrite and back into RightMark.
Any other clever ideas? I figure my laptop is probably the noisiest one. This of course does not take into account any effort the DAC has done to be immune. I am not sure my systems have a problem to fix, but I wound up with them for a USB scope which I returned. So might as well.
I was thinking of generating a "perfect" 1K tone on the PC, then send it through the two isolators to various DACs, into my Focusrite and back into RightMark.
Any other clever ideas? I figure my laptop is probably the noisiest one. This of course does not take into account any effort the DAC has done to be immune. I am not sure my systems have a problem to fix, but I wound up with them for a USB scope which I returned. So might as well.
I know my question is late to the mark, but why do you consider the Asgard a "silly" design? Do you have some idea that everything MUST be balanced? They will sell a more expensive one that is. And the on-board DAC is not very good. I use an Atom DAC+. SINGLE ENDED. NO GROUND LOOP, NO PROBLEM. My headphones are not balanced, and neither is my power amp. SE suits me fine.
When it comes to ground loops and computer noise I don't think you need much testing beyond turning up the volume and putting year ear near the drivers and listening to see if you can hear anything.
tvrgeek
Major Contributor
That is why I don't think I have an audible problem. But when I scoped the lines, there was a lot of hash and the Linear Tech isolator cleaned it completely. I have one of the cheap things like in a picture above, ( post 41) but not too sure how "proper" they are as the transformer module on the LT is $40 itself, but it is a true instrumentation /medical grade device.
Yes, to see if you have a problem, your ear is just fine. Can we say that on a site with folks that do not believe we hear anything if we can't measure it? I kind of wanted to know if a $12 Chinese wonder performs as well as one I trust. Of course, reading the LT documentation, a well executed USB interface has several more devices for protection before the actual receiver. Al l three of my "music" DACs are line powered so that limitation is not an issue, but not sure either can power the Focusrite. May have to whip up a clean 5V supply.
Yes, to see if you have a problem, your ear is just fine. Can we say that on a site with folks that do not believe we hear anything if we can't measure it? I kind of wanted to know if a $12 Chinese wonder performs as well as one I trust. Of course, reading the LT documentation, a well executed USB interface has several more devices for protection before the actual receiver. Al l three of my "music" DACs are line powered so that limitation is not an issue, but not sure either can power the Focusrite. May have to whip up a clean 5V supply.
Same SPDIF coaxial input DAC, two SPDIF sources, one has isolation transformer (as per required by SPDIF standard), the other is a computer motherboard. Measured by a soundcard in the same computer so there is a ground loop from (motherboard -> DAC -> soundcard -> motherboard).
And honestly, as bad as the green graph looks in comparison, it is still at the level of computer motherboard sound or maybe slightly better. So still within the criteria of "inaudible".
Note that dB levels should be taken as relative instead of absolute due to unknown amount of "FFT gain"
And honestly, as bad as the green graph looks in comparison, it is still at the level of computer motherboard sound or maybe slightly better. So still within the criteria of "inaudible".
Note that dB levels should be taken as relative instead of absolute due to unknown amount of "FFT gain"
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