USB Isolation - what are the current options?

[ggking7]

I've been very happy using a DIY Paradise Ultravox USB isolator powered via an SLA battery, but unfortunately I just fried the Ultravox when one of its power leads broke and I tried to fix it. Since I'm back to square one now, I thought I'd check with you guys to see if anyone has found another good USB isolation method. I have to admit dealing with the battery was getting old. Anything else out there?

 

[Mr.C]

I was considering the Opticis usb extender for isolation.

 

[ggking7]

After some research I'm realizing that the right way to isolate is to build it into the DAC. I believe the Ayre QB-9 and HRT Music Streamers do this. Are there others?

 

[ggking7]

Has anyone tried this?

 

http://electronicsshop.dk/usb2iso.htm?currency=USD

 

[The Computer Audiophile]

Hi ggking - I haven't tried this device but did notice it only supports full speed USB, not HiSpeed ISB. Some new converters require HiSpeed.

 

[Part-Time Audiophile]

I think this only supports USB 1.1, no?

 

[moschlegel]

 

I just noticed this patent by Finisar

OPTO-ISOLATOR INCLUDING A VERTICAL CAVITY SURFACE EMITTING LASER

http://www.freepatentsonline.com/y2011/0057128.html

 

Where they note the benefit of using the VCSEL is to get beyond the slowish speed of LEDs. Maybe this will result in fast isolators for things like usb 2 and usb 3.

 

There's also the Adnaco-R1USB (a card goes in the PC sending data down an optical cable to a remote USB 2.0 unit.). But again that's $385 (http://www.adnaco.com/products/r1usb/). Plus again, how quiet is the power and hardware in the remote unit?

 

Next would be Thunderbolt (optical version -- not here yet). The only really good usb isolator I see now is this special usb adapter card:

http://www.sonore.us/SOtM.html

 

nearly the same price as the Adnaco but at least it's tailored to the job as it's only a usb card and you don't use an optical fiber and you can flip off the power on the usb cable entirely or put your own power into the PC side via the molex port.

 

Again, maybe some day that laser based isolator will be available.

 

[PeterSt]

There's also the Adnaco-R1USB (a card goes in the PC sending data down an optical cable to a remote USB 2.0 unit.). But again that's $385 (http://www.adnaco.com/products/r1usb/). Plus again, how quiet is the power and hardware in the remote unit?

 

I didn't check it today, but by heart this is too cheap and you possibly forget some interface at one end (carrying the same price).

 

Besides, I think that it can well be that nobody is answering the phone there.

The product they carry is good IMO, but the "company" looks like air to me. At least I never could get something from them. Not two years back, not one year back, and I tried. Still I talked in terms of 100s.

 

Peter

 

[ferenc]

Why not try Icron USB Ranger® 2101 USB2 - Cat5e interface? Works extremely well even with 384kHz/32 bit files. There is a small impulse transformer in the receiver and there is power supply for the receiver as the transmitter did not provide power. Much cheaper than any of the optical converters. You do not need more. I am using one at home, works perfectly well.

 

http://www.icron.com/products/usb_new/usb20_ranger_2101_2104.php

 

[moschlegel]

Does the transformer block hum and ground loops? Or does it just cut noise down a bit but not all the way? The problem I have is that computers have switching supplies and noisy power mosfets that get down the usb cable.

 

I'm leaning in the direction of getting one of those super low power units like a soekris or a ALIX so it's easy and cheap to use a really quiet linear supply and avoid the switching supply issue entirely.

 

I almost bought a Soekris net5501-70 but then discovered they have a pretty bad restock fee policy so I dropped the order.

Still looking for a reasonable seller....

 

 

[ferenc]

The Icron breakes the ground and if there is no ground loop, there will be no hum. At least I have no noise problem with a 100 (98) dB sensitive speakers and the 130 dB signal-to-noise ratio amp.

 

[moschlegel]

I was having a buzz problem (mostly noticable between songs) caused by the cheap wall wart used by my alix mpd server.

The hash noise was going up the cable shield I think and polluting my DAC. I was able to fix it by putting this unit in series with the usb cable from the alix to the DAC

 

http://www.olimex.com/dev/usb-iso.html

 

Again, this sort of thing only works for the slower usb speeds (not the 480MBit/sec)

 

The silence was so big a difference I suspected it wasn't working and had to go play a song.