There are several types of these "thumbdrive"-like devices avail.
Some are dedicated (and $$) audiophile products, like:
AudioQuest Jitter Bug (this is passive):
And there are "active" devices for audio:
HiFimeDIY USB Isolator -- USD29.99
HiFimeDIY state that:
====================
The following are generic USB filters (not necess. audio) :
HiLetgo ADUM3160 B0505S 1500V USB to USB Voltage Isolator Module Support 12Mbps 1.5Mbps --- $15.00 USD
diymore 1500V USB to USB Isolator Board Protection Isolation ADUM4160 ADUM3160 Module -- $15.00USD
=========
Say your primary source for audio is a laptop. Nothing special.
Would you select any one of these for your USB dac? Why or why not? And how important (to audio) is speed and active vs. passive?
Suggest some alternatives.
Thanks!
Some are dedicated (and $$) audiophile products, like:
AudioQuest Jitter Bug (this is passive):
And there are "active" devices for audio:
HiFimeDIY USB Isolator -- USD29.99
HiFimeDIY state that:
So they suggest their $100 "Hifime High-Speed USB Isolator version" for "hi-speed" because:
====================
The following are generic USB filters (not necess. audio) :
HiLetgo ADUM3160 B0505S 1500V USB to USB Voltage Isolator Module Support 12Mbps 1.5Mbps --- $15.00 USD
diymore 1500V USB to USB Isolator Board Protection Isolation ADUM4160 ADUM3160 Module -- $15.00USD
=========
Say your primary source for audio is a laptop. Nothing special.
Would you select any one of these for your USB dac? Why or why not? And how important (to audio) is speed and active vs. passive?
Suggest some alternatives.
Thanks!
For example, assume this is your DAC:
Hifime S2 - USB DAC with Sabre ES9038Q2M ($90usd)
You can clearly see what a stock DAC is filtering by itself. And what the company selling it is trying to sell AGAIN to you (see above post) to "upgrade" it's sound.
Note the price of the DAC ($90usd) vs. the "upgrade" ($30-100).
Hifime S2 - USB DAC with Sabre ES9038Q2M ($90usd)
You can clearly see what a stock DAC is filtering by itself. And what the company selling it is trying to sell AGAIN to you (see above post) to "upgrade" it's sound.
Note the price of the DAC ($90usd) vs. the "upgrade" ($30-100).
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you might want to read this:
AudioQuest JitterBug USB Filter Review | Audio Science Review (ASR) Forum
AudioQuest JitterBug USB Filter Review | Audio Science Review (ASR) Forum
Forget the Audio Science Review stuff. This guy is spreading nonsense.
Instead of measuring filters, he measures DACs and then he rates the filters.
Here is one example of what a
well regarded isolator does.
Active devices are the better choice. By using a HUB chip they reclock and regenerate the
stream beside filtering the cable up to 40dB of noise.
Modern devices support USB3.0. Which of course is an noise source on it's own. There are limits.
Anyhow. Feeding clean power usually also helps.
But. The impact depends on the filter capabilities of the DAC. Some do better, others do worse. I've seen none that's been immune on upstream induced flaws.
Just as an example.
My setup:
I am running a RPI4 and a Gustard A18 (which measures extremely well over @ASR btw)
My USB link is a Ghent Audio JSSG360 USB cable, an iFi iPurifier 2 and an iFi iDefender fed by an Allo Shanti.
I also tested also these EBAY and HifiMe stuff. Above is the result after fighting USB flaws for a long long time.
Enjoy.
Instead of measuring filters, he measures DACs and then he rates the filters.
Here is one example of what a
well regarded isolator does.
Active devices are the better choice. By using a HUB chip they reclock and regenerate the
stream beside filtering the cable up to 40dB of noise.
Modern devices support USB3.0. Which of course is an noise source on it's own. There are limits.
Anyhow. Feeding clean power usually also helps.
But. The impact depends on the filter capabilities of the DAC. Some do better, others do worse. I've seen none that's been immune on upstream induced flaws.
Just as an example.
My setup:
I am running a RPI4 and a Gustard A18 (which measures extremely well over @ASR btw)
My USB link is a Ghent Audio JSSG360 USB cable, an iFi iPurifier 2 and an iFi iDefender fed by an Allo Shanti.
I also tested also these EBAY and HifiMe stuff. Above is the result after fighting USB flaws for a long long time.
Enjoy.
These are likely not hub chips. There are dedicated regenerator chips for this that include galvanic or optical isolation circuitry for this purpose. They are actually rather cheap. I use a small isolator for just the purpose of posing impedance to noise. The galvanic isolation is a higher impedance than the DAC's internal data circuitry and hence it will provide more resistance to all this noise.
As far as I know, the Jitterbug has actually not direct impact on jitter and is just a ripple rejection bypass cap. While this can help you are also inducing extra capacitance across the lines which in terms of USB standard can actually cause more jitter rather than decreasing it because of the very finicky nature of the differential signaling.
The latter ones that use the ADUM isolator is exactly the one I use. They are all operating on the same principle and will have no extra effect on audio quality. Only power quality. The signal is regenerated by the isolator in a copy way. You would not select one over the other if you are just dealing with noise leaking over the data lines. Though at that point there are also more serious issues than just the isolation - Where is the noise coming from?
Regarding USB Full speed spec: this is actually plenty for most dacs and sampling rates youll be using. Your normal DAC does not need a lot of throughput to produce a signal because you are not using much more bandwidth than literally the decoded PCM stream will be using.
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If you ask around on Audio Science Review -- "It's all snakeoil"
I am saying it is all BS. Why?
Because it works very well for me!
There are other products, there are other setups. Other solutions can work very well.
But please stay away from that low Q stuff.
And. The Allo device comes with much more issues than the rest of the bunch.
There's much I don't like about that device.
The iDefender was the last thing I added btw.
Why?
It all sounded OK with the rest of the bunch.
I was still experiencing bloat and clouding in busy pieces with acoustic low end
instruments. It's been annoying. I had to switch tracks when it happened.
I recalled having an iDefender somewhere. Since I feed ma PI with the Shanti
anyhow I had 5V outlet sitting idle. Great.
Bottom line. As soon as it was in, the bloat was gone. Crystal clear playback.
And folks. Isolation is not always a good thing. Especially if you catch the mess
through the backdoors (mains/rca/air)
Enjoy.
^^^This.
If you source is PC/Laptop, find something that redirects ground loops to its own PSU. Even a self-powered USB 2.0 hub will do (avoid 3x hubs). Use a quality LPS and remove a bridge (diode) transfering power from the USB source. IF a DAC do not use USB bus power, modify ground connection, adding 1-5 Ohm resistor in series. Use ferrite clamp on the DAC USB cable.
It should work well in most cases. When still looking for a galvanic isolation, rather convert USB to I2S or S/PDIF. These isolators are more effective. It can be a 'poorman' DDC like this: https://www.amazon.com/Digital-Interface-Coaxial-Optical-Audio/dp/B08HN3VSF8/
I will get one soon. it doesn't provide isolation on I2S. Upgrade oscilators to a low jitter parts.
If you source is PC/Laptop, find something that redirects ground loops to its own PSU. Even a self-powered USB 2.0 hub will do (avoid 3x hubs). Use a quality LPS and remove a bridge (diode) transfering power from the USB source. IF a DAC do not use USB bus power, modify ground connection, adding 1-5 Ohm resistor in series. Use ferrite clamp on the DAC USB cable.
It should work well in most cases. When still looking for a galvanic isolation, rather convert USB to I2S or S/PDIF. These isolators are more effective. It can be a 'poorman' DDC like this: https://www.amazon.com/Digital-Interface-Coaxial-Optical-Audio/dp/B08HN3VSF8/
I will get one soon. it doesn't provide isolation on I2S. Upgrade oscilators to a low jitter parts.
There is only one IC that working with contemporary USB/I2S interfaces (Amanero, XMOS etc.)
By Silanna. But unfortunatly they dont make them any more
I tried ALL, AD,LT and so and they DOES NOT working. (working with mouse, usb sticks and so but not with audio)
.
Intona used 2 low speed isolators for bidirectional transfer, BUT with CPLD before and after isolation barrier.
.
Silanna chip working fine, sound is a bit more analog with. I can say from the short tests.
.
The main issue is inerfacing and protection circuit at the USB port. Google USB sheild.
.
Also very good papers AND components coming from Wurth
The Protection of USB 2.0 Applications | Wurth Elektronik: Electronic & Electromechanical Components > Products & Services > Application Notes
.
cheers
By Silanna. But unfortunatly they dont make them any more
I tried ALL, AD,LT and so and they DOES NOT working. (working with mouse, usb sticks and so but not with audio)
.
Intona used 2 low speed isolators for bidirectional transfer, BUT with CPLD before and after isolation barrier.
.
Silanna chip working fine, sound is a bit more analog with. I can say from the short tests.
.
The main issue is inerfacing and protection circuit at the USB port. Google USB sheild.
.
Also very good papers AND components coming from Wurth
The Protection of USB 2.0 Applications | Wurth Elektronik: Electronic & Electromechanical Components > Products & Services > Application Notes
.
cheers
12MBit @ $75
Guys. If you like isolation. Have a look at the Intona devices
Keep in mind though. USB isolation is like putting just a glove on while you're standing with your naked body in a blizzard and hoping not to freeze.
If you go the isolation route you should do it on all devices/cables/interfaces in your system.
And don't forget. The secondary side of an isolator usually introduces its own issues which need to be addressed!
Otherwise simply apply proper grounding which implies avoidance of ground-loops.
This whole subject is not as easy as it seems to some. It's a subject we have on the table for more than a decade.
And again. Active USB filters have hubs (or regenerators) inside. We've been working with standard USB HUBs in the early days. This actually led to these USB AUDIO filters/regenerators. Going back to USB HUBs would be like turning the clock back for about a decade.
Of course there are many ways to approach the subject.
I now mostly stick to commercial products because they work, they are flexible and easy to apply. And keep my DIY efforts to a minimum. Beside that with all that DIY stuff in the digital area, you'll never know what you end up with.
Instead of spending $75 on a 12MBit proto board I rather buy an USB3 iPurifier.
Enjoy.
Guys. If you like isolation. Have a look at the Intona devices
Keep in mind though. USB isolation is like putting just a glove on while you're standing with your naked body in a blizzard and hoping not to freeze.
If you go the isolation route you should do it on all devices/cables/interfaces in your system.
And don't forget. The secondary side of an isolator usually introduces its own issues which need to be addressed!
Otherwise simply apply proper grounding which implies avoidance of ground-loops.
This whole subject is not as easy as it seems to some. It's a subject we have on the table for more than a decade.
And again. Active USB filters have hubs (or regenerators) inside. We've been working with standard USB HUBs in the early days. This actually led to these USB AUDIO filters/regenerators. Going back to USB HUBs would be like turning the clock back for about a decade.
Of course there are many ways to approach the subject.
I now mostly stick to commercial products because they work, they are flexible and easy to apply. And keep my DIY efforts to a minimum. Beside that with all that DIY stuff in the digital area, you'll never know what you end up with.
Instead of spending $75 on a 12MBit proto board I rather buy an USB3 iPurifier.
Enjoy.
There is only one IC that working with contemporary USB/I2S interfaces (Amanero, XMOS etc.)
By Silanna. But unfortunatly they dont make them any more
I tried ALL, AD,LT and so and they DOES NOT working. (working with mouse, usb sticks and so but not with audio)
.
Intona used 2 low speed isolators for bidirectional transfer, BUT with CPLD before and after isolation barrier.
.
Silanna chip working fine, sound is a bit more analog with. I can say from the short tests.
.
The main issue is inerfacing and protection circuit at the USB port. Google USB sheild.
.
Also very good papers AND components coming from Wurth
The Protection of USB 2.0 Applications | Wurth Elektronik: Electronic & Electromechanical Components > Products & Services > Application Notes
.
cheers
Oh IC. Thanks for the great information. Cheers!
12MBit @ $75
Guys. If you like isolation. Have a look at the Intona devices
Keep in mind though. USB isolation is like putting just a glove on while you're standing with your naked body in a blizzard and hoping not to freeze.
If you go the isolation route you should do it on all devices/cables/interfaces in your system.
And don't forget. The secondary side of an isolator usually introduces its own issues which need to be addressed!
Otherwise simply apply proper grounding which implies avoidance of ground-loops.
This whole subject is not as easy as it seems to some. It's a subject we have on the table for more than a decade.
And again. Active USB filters have hubs (or regenerators) inside. We've been working with standard USB HUBs in the early days. This actually led to these USB AUDIO filters/regenerators. Going back to USB HUBs would be like turning the clock back for about a decade.
Of course there are many ways to approach the subject.
I now mostly stick to commercial products because they work, they are flexible and easy to apply. And keep my DIY efforts to a minimum. Beside that with all that DIY stuff in the digital area, you'll never know what you end up with.
Instead of spending $75 on a 12MBit proto board I rather buy an USB3 iPurifier.
Enjoy.
Btw, do you meant this?
iPurifier3 by iFi audio | USB Audio and Data Signal Filter
