High-Speed or Low-Power?

[cfmsp]

 

As for galvanic isolation, I'd check directly with Charles Hansen about the types of isolation he's using with the Ayre QB-9.

 

Charles has done more with 'isolation' than anyone else in this space, to my knowledge.

 

cheers,

clay

 

 

 

 

[Elprior]

Clay said thanks much for the heads-up. A quick Google search and I notice that Kent Poon has selected them for his Weiss DACs, which is a good endorsement. $700 HK equals about $90 US if I did the FX conversion properly.

I'll be giving these a try with the LIO-8 soon.

 

You're welcome Clay

In France, it costs roughly 120€, which is quite more than your 90$ computation, but still very acceptable considering the overall quality of their line. They even have a 240€ version, but I am unsure about the differences.

I'll test the int202 with a stock cable first, but I am pretty sure I'll want to listen to one of these.

 

Chris said Common non-audiophile thinking would suggest isolation inside the DAC is enough. But, is it really? I wonder if there are better levels of isolation.

 

I've been asking Daniel Weiss about the pollution from the int202 interface to the dac (well passing from the pc to the dac through the int202 to be more precise).

He suggested that I isolate the ground pin of the dual/aes connection to the dac.

As for isolating the firewire power bus, this is not recommended since the int202 isolates it automatically when an external psu is used (even if you want to do so, the ground pin must not be isolated).

That led me to asking for a linear external psu, but Daniel suggested this is not necessary, since there are regulators inside the int202.

 

Well, well, well, that leaves me with the cable track only.

I may still try a linear psu, should I keep the int202 (you are what you are ).

 

Elp

 

[ggking7]

Lars used the Opticis USB - to Optical - to USB converter, as I mentioned earlier, and it was displaced by as RSA USB cable.

 

That is likely because of the cheap and low quality power supply shipped with the Opticus cable.

 

Besides optical conversion, there is another method of USB isolation incorporating the Analog Devices ADUM4160, and I'll be powering both it and the Proton DAC with a small SLA battery. I'll be using the DIY Paradise Ultravox which includes a linear voltage regulator:

 

http://diyparadise.com/shop/index.php?main_page=product_info&cPath=3&products_id=124

 

This should be a recipe for total isolation and incredible sound. Theoretically, it should be drastically better than any USB cable, but I don't know what RSA USB is. Can you point me to a web page with more info on it? Google isn't helping.

 

[Christopher]

Hi ggking7,

 

I believe the RSA USB is a product offered by Ridge Street Audio. Below is a link:

 

http://home.comcast.net/~ridgestreetaudio/Poiema_USB_40_Ad.html

 

Please keep us posted on your experience with the DIY Paradise Ultravox that uses the ADUM4160. I am also interested in upgrading my USB cable and am considering products that use the same chip.

 

Best regards,

Chris

 

 

[cfmsp]

 

 

GG,

 

Great stuff, thanks for sharing.

 

For some reason I have the impression you'd consulted with Gordon on this setup?

 

Please report the results of your listening comparisons here for the benefit of all.

 

As Socrates7 knows, I'm not a fan of expensive USB cables, so I"d be very interested in correcting issues with USB "in other ways".

 

Note: I use a Proton as my travel/backup/weekend home DAC, and 'cause my Metric Halo boxes provide every other type of interface except (Async) USB.

 

 

 

 

And, yes, Christopher you found the cable manufacturer - Ridge Street Audio.

 

cheers,

clay

 

 

 

 

 

 

 

 

 

[ggking7]

Gordon did advise me to go this route. He said a friend of his had achieved extremely good results with the Proton, Opticus cable and an SLA battery, and he thought the ADUM4160 would produce even better results. The Ultravox + SLA battery setup is very inexpensive, well under $100. I'll definitely let everyone know how it goes. Hopefully I'll put together some good photos too.

 

I have a feeling USB isolation is the missing link in my system. For example, since upgrading from a Belkin USB cable to a Starlight, the sound has definitely improved, but what's even more interesting is the dishwasher, electric stove, and electric water heater don't seem to affect the sound to the same degree they used to. I had previously concluded the electrical noise from these appliances (2 of which are on the same circuit as the audio system) was making its way to the amp and fouling the sound that way. Now that the Starlight USB cable is preventing this from happening to a large degree, I realize the foul sound must have been the result of the electrical noise making its way into the computer and then to the DAC instead of the amp. Of course, USB isolation will completely prevent this from happening.

 

Another example is what I posted about at the beginning of this thread. Many different computer hardware and software tweaks affecting the sound is disconcerting. Ideally, the computer should be a perfect and neutral transport and shouldn't affect the sound at all when outputting bit-perfect and used in conjunction with a good asynchronous DAC. Of course, it does. I'm hoping this is the result of electrical noise generated by the computer, which is affected by hardware and software tweaks. If that's true, perfect USB isolation will completely eliminate it and allow the computer to make as much electrical noise as it wants without sonic consequence. I can't wait to hear how it sounds.

 

[cfmsp]

 

GG,

 

You may be on to something here that's not been discussed/explored that often.

 

Seemingly the length of the Opticus cable would be non-critical as well? ... which would allot those such as ZZ to put the computer in another room entirely (without having to rely on just on those providing Ethernet DACs).

 

 

cheers,

clay

 

 

 

[ggking7]

Once you really are just passing digital data (and not collecting electrical noise) like with the Opticus cable, the length of the cable shouldn't matter at all.