I think I might have started the trend several years ago to drop the voltage / vbus line from my usb cables where the dac would happily operate without one. As such, I feel slightly responsible for some of the confusion arising from this subject.....
Why would you want to use an unpowered cable? Well, quite simply it sounds better as it prevents noise from the server from being carried into the dac. This means that you can get away with a simplified and shorter cable, which I offer at a lower price than my regular model. Cheaper and better, what’s not to like?!?
Who can use an unpowered cable? Unfortunately only a handful of brands manage to enact server handshake / recognition without vbus and they all happen to use either Amanero or JLSounds usb input cards. Lampizator, Mojo Audio, Matrix X-Spdif, Nagra, SOTM TX Ultra and T&A are some widely owned examples.
A word to the wise - several dac builders over the years have answered incorrectly when asked whether their dacs can operate in this manner - so if in doubt, you most likely need a vbus cable even if the dac powers its usb input internally. In a similar vein, some servers themselves will need a voltage cable for handshake even if the dac doesn’t, however these are in a minority.
You can easily test this out at home by putting a piece of tape over the pin one metal contact of the dac’s usb input to isolate vbus and seeing if your system plays music afterwards. If so, you will likely have already achieved an improvement in sound quality with your existing usb cable. Free upgrade!
Why would you want to use an unpowered cable? Well, quite simply it sounds better as it prevents noise from the server from being carried into the dac. This means that you can get away with a simplified and shorter cable, which I offer at a lower price than my regular model. Cheaper and better, what’s not to like?!?
Who can use an unpowered cable? Unfortunately only a handful of brands manage to enact server handshake / recognition without vbus and they all happen to use either Amanero or JLSounds usb input cards. Lampizator, Mojo Audio, Matrix X-Spdif, Nagra, SOTM TX Ultra and T&A are some widely owned examples.
A word to the wise - several dac builders over the years have answered incorrectly when asked whether their dacs can operate in this manner - so if in doubt, you most likely need a vbus cable even if the dac powers its usb input internally. In a similar vein, some servers themselves will need a voltage cable for handshake even if the dac doesn’t, however these are in a minority.
You can easily test this out at home by putting a piece of tape over the pin one metal contact of the dac’s usb input to isolate vbus and seeing if your system plays music afterwards. If so, you will likely have already achieved an improvement in sound quality with your existing usb cable. Free upgrade!