Topping HS02 USB isolator early impressions

[Norville]

I couldn't find a lot of information about the Topping HS02 USB isolator online from people actually using one so I thought I'd post some of my early impressions of using it.
I had a pretty bad noise coming out of the USB connections from my PC motherboard. It didn't matter if I had the output actually switched on on my Topping E50 DAC
running through USB or not, there was still noise that seemed to follow the movement of the mouse or when the Graphics card was under load. The only way to make it stop was to remove the usb cable from the motherboard.

I did some looking online and found that a a ground loop isolator would probably do the trick.
So I ordered a Topping HS02, which I found was the most solid option since it could be powered with a separate power supply if the DAC actually needed USB-power which makes it a bit more versatile for other applications. There is a HS01 too, but the 20 dollars more expensive HS02 has the seperate USB-power filtered too.

One could argue that this is a design flaw of the DAC, it should be able to isolate ground loops by itself. I also have a Matrix Element-i which doesn't have any of these problems when connected as a USB-DAC but it is much more expensive on the other hand.

Anyway, got it today and my early impressions are very positive. It's quite small, like a packet of Tic-Tacs and solidly built with metal.
The noise has virtually disappeard when it was plugged in. There still is some very slight noise coming from my active KRK Rokit 6 monitors but it's nowhere
near as bad as it used to be. Seems to be a very solid upgrade for those that have the same problem.

 

[Matias]

The noise has virtually disappeard when it was plugged in. There still is some very slight noise coming from my active KRK Rokit 6 monitors but it's nowhere near as bad as it used to be.

Same kind of noise (mouse movement, GPU load) but attenuated, or just constant background hiss?

 

[Norville]

Same kind of noise (mouse movement, GPU load) but attenuated, or just constant background hiss?

No noise following mouse movement or GPU load. I think the speakers themselves have some background noise from the factory and it is with high volume with nothing playing.

 

[Matias]

Yes, then the HS02 solved 100% of the USB noise interference, and now what is left is only the speaker plate amp limitation. The HS02 removed a bottleneck and revealed the next one downstream.

 

[Norville]

Yes, then the HS02 solved 100% of the USB noise interference, and now what is left is only the speaker plate amp limitation. The HS02 removed a bottleneck and revealed the next one downstream.

You are most likely right. I don't mind that noise however, that's really something I can live with compared to how it was.

 

[Loomynarty]

If I had to take a wild guess what IC this isolator is using, it's probably the relatively new ADuM 4165 from Analog Devices. I haven't found any isolator state outright they're using this IC but considering AD are pretty much the only company making USB isolator ICs that actually work, it'd be safe to say it is that.

You can actually buy an evaluation board with said IC installed in it directly from AD to test if you're curious. I'm thinking about ordering one.

 

[mike7877]

I thought I'd add some of my experience with this isolator here for other people who come across this thread. It works great - you have two inputs and two outputs, there's a switch on either side so you can pick which you'd like to use. One excellent feature is this: say your device draws too much power for phone's USB port - connecting your battery bank to the second USB input splits the load between the two inputs. It doesn't take it all from the second port, though - it's a balancing act. To put it simply (and not entirely accurately{re: the numbers}): port 1 and port 2's voltage will appear the same at the HS02's inputs. If your battery bank has a shorter thicker wire, and a more robust power supply circuit on its output than your phone's USB port, most of the power will be coming from your battery bank. Just how it is! If your phone gets overloaded or just chooses to stop providing power over USB, and still communicates data to the DAC (or whatever device), all of the power will be drawn from the battery bank in that situation.

Whenever any noisy USB power supply has caused issue for a device, or I've connected my PC to various things over USB and there've been problems, if those problems were related to an isolation/grounding issue,, the HS02 fixed it completely. Yes, 100% completely. And not only does it isolate, it regenerates power! Power that is very clean.
Also, about latency - it's low... reaaaalllllyy low:
72 microseconds. If you run 1ms (2ms round trip) my RME Babyface does 1ms one way/2ms both, and it won't pop (when PC conditions are right lol), 72us is just 7.2% longer in this [worst] case. Most often people are running 2-3ms doubled to 4-6. HS02 latency is negligible!

Last thing: it can get warm. For example, when running my RME Babyface Pro, which draws about 550mA idle, 650-700 under peak load (driving headphones), the outer case reaches 45C in a 23C room. Not hot enough to burn you, but it's metal so feels hot. Because the output is regenerated and very clean, for the 550mA to be available, about 800mA is drawn, and yep, you guessed it, that 250mA@5V or 1.25W, all gets dissipated as heat. 1.25 watts doesn't seem like a lot, but if you, say, sit on the thing, very quickly, that heat can have nowhere to go, and within 10 minutes it'll be over 70C and a small spot of your leg will slowly be cooking

 

[Rockfella]

This is a good find/info thx for sharing.

 

[carsknivesbeer]

I find the HS01 to work great and is an audible improvement. I am hoping that someone does a comparison to the new JDS Labs Synapse which does the same thing. IF my HS01 dies, that will be its replacement but it has been running along (albeit warm) for 2 years so far though.

Sure wish Mac wouldn't have ditched the Toslink out and this wouldn't be an issue...