Uptone Audio Regen

[Sergey_S]

Hey, guys, 

Vbus2 has a compatibility list, and any of my DACs are on it. 

If I am to add Uptone Regen to this, say: 

PC > Vbus2 > USB Cable > Uptone Regen > USPCB A>B Adapter > DAC (PS Audio)
will any DAC then be recognizable by the PC or that DAC still must be Compatible with Vbus2? 

Or could that be that DACs such as PS Audio (DS DAC or Gain Cell DAC) won't benefit from such 'tweak'? 

Thank you!
Sergey

[Sergey_S]

36 minutes ago, Superdad said:

 

Hi Sergey:

 

The Vbus2 from SBooster does nothing more than disconnect Pin 1 of the USB cable, thus turning off 5VBUS by not passing it through.  A piece of tape on Pin1 would do exactly the same thing.

 

For the chain you show, with our original USB REGEN, the Vbus2 would do nothing because the USB REGEN already does not use or connect Pin 1.  The USB ignores that 5VBUS and dedicates a 1 amp ultra-low-noise regulator to producing clean 5VBUS at its output for DACs that need it. (Your PS Audio DAC, while not using VBUS to power much, does need to see VBUS for its initial "handshake" connection.)

 

Actually, I will correct myself here:

Since you are running a USB cable of some length from you computer to the USB REGEN, using the Vbus2 at the computer end to disconnect VBUS might have a very small benefit. The possible benefit would be not having the voltage running along the wire and capacitively coupling to it.  So you can try it and see here.

 

One important note to others that may read this:

Disconnecting VBUS leading into an UpTone REGEN can only be done for the original USB REGEN (of which there are close to 4,000 in the field).  Our ISO REGEN does require a tiny amount (20mA) of 5VBUS to power the upstream side of its Silanna galvanic isolator chip (though we even go overboard there and dedicate an ultra-ultra-low noise LT3042 to turn 5V into 3.3V for the chip, skipping the Silanna's internal reg.).

 

Regards,

--Alex C.

Thank you so much, Alex!
Now it's much clearer. I just tried the tape stripe and my PC doesn't see the DAC! 

I accidentally 😬 bought that Vbus2 thing without looking at compatibility list first! (I think I confused it's description with Uptone Regen description where I just need to connect it to anything as I was looking at many things that night).

And "https://www.audioaffair.co.uk/" (where I purchased Vbus2) never replied in this regard, so I guess I'm stuck with this device. Good thing it's not expensive. 

Anyway, since I am stuck with it, I thought to find some use of it, that's why I was thinking about getting an Original Uptone Regen. Seems like it's available at http://www.vortexbox.co.uk/.

I saw a few images on the Internet with Vbus2 connected to Uptone Regen and thought that should be a good use of Vbus2, better isolation etc, etc.. but seems like it doesn't make any sense to connect this way. 

I'm not quite sure what that means:
"The possible benefit would be not having the voltage running along the wire and capacitively coupling to it."
Does this mean that Vbus2 should be just connected somewhere else in the chain?

Like, say: PC > USB cable > Vbus2 > Uptone Regen > USPCB > DAC? 

Sorry if those are silly questions, it's just that when I connected Chord Mojo to this same PC I've heard those crazy ground loop noises coming out of the speakers. It's completely silent with the same speakers when I use MacBook Pro or other things like iPod or Cell phone. I disconnected PC's ground pin from the plug and it was silent, so I figured it's that ground loop noise people talk about. 

I've never heard this noise before however, and with PS Audio DACs it's also silent. But I'm just thinking, if that noise is somehow in the signal that is coming from this PC, maybe it somehow affects the music? 

It sounds ok from this PC's USB, but MacBook Pro sounds better (to my hearing) for some reason with the same DAC and Speakers using same Audirvana. 

Also, I like the sound much more that direct USB using USB Bluetooth Transmitter (Avantree Leaf) from the PC and BT Receiver connecting (Audioengine B1) it with Toslink cable to the DAC. Could that something to do with complete isolation from 5VBUS?

So that also makes me wonder whether something is messing with that direct USB signal. It's bit perfect, when I test it with DS DAC, but too "dry" and "boring" comparing to MacBook Pro or Bluetooth Connection. 

Maybe it's even better to get USB to SPDIF converter?

Thank you again, really appreciate your responses. 
Sergey
 

[Sergey_S]

Great, thanks, Alex! 😃

Yeah, I mentioned few "mysteries" here, in case someone has the answers already.