USB bashers, show us your evidence.

[idc]

To those who bash USB as a means of connecting PC to DAC by stating there are electrical/interference or other issues which make optical of digital coax better, care to share some evidence to back up your claims?

 

[John Duncan]

Yes. Laptop plugged into mains into dac via USB, mains interference. Laptop via optical to dac, nomains interference. Note that it wad at a *much* lower level than via the audio our, but it was there nonetheless. That notwithstanding, I can't claim a real world audio superiority from optical so use USB exclusively.

 

[Anonymous]

I'm not a basher, but optical makes use of light therefore can't be subject to electrical interference.

There's some interesting articles on a website for stereophiles that go into this in some depth, not to mention some papers on the Naim site too, if memory serves me well.

However, USB in theory should be as good if not better, though there are those who claim firewire is inherently a cut above both.

Personally, over long distances I prefer optical cables.

 

[idc]

OK so at times some mains interference, which I solved with a mains conditioner as the slight background hiss all but disappeared. But that was with a Sony Vaio, there wasn't any with the previous DELL, which is assume is a floating earth issue that could have also been solved with a ground loop.

 

[Anonymous]

So why don't you like optical? You wouldn't have needed a conditioner.

 

[idc]

There was no optical out on the Dell, I do not think there is one on the Sony and my DAC has only USB. It is not that I dislike optical, it is just USB gets a bashing and I have read plenty of reviews which suggest it is fine. The implementation of the DAC is far more important.

You may have noticed that since I made my own cables, read up extensively on cables and blind/ABX testing I have come off the fence and am now a cable sceptic.

Hence USB vs optical vs digital coax, I don't really accept that unless it is backed up by science. The one issue that is clear is that longer runs of cable and I mean very long as in 50m plus may not be advisable for the likes of USB.

The conditioner helps with noise out of the mp anyway. Background hiss is more noticeable with headphones.

 

[Anonymous]

Er - have a look at USB.org. Think you'll find the recommended single cable run is a bit less than 50m for USB...

 

[PJPro]

Cable sceptic or not, there are clear differences between the construction of USB, coax and optical.

One cannot ignore the lack of an electrical connection when using optical. So, where noise/interference/ground loops/etc are an issue, the optical route is worth considering as a possible "work around".

That said, I do tend to favour devices which give me optical as an option....primarily so I have the work around available if I need it.

 

[idc]

USB has the advantage of its power supply allowing USB DACs and other products to appear which only need a USB connection. So the electrical connection is a double edged sword. No one seems to bash coax digital in the same way as USB.