[landgreen]

Using Itunes on an Asus netbook with .m4a files via USB to DLiii Dac then Woo amp.
Is there significant difference using an expensive USB cable to the DAC? ie Is there any data loss with "normal" USB cable?
Does changing the volume level in Itunes change the data flowing from computer to DAC in any way other than volume?
Thanks

 

[DougofTheAbaci]

If I'm not mistaken (highly possible) changing the volume does nothing more than increase the power being pushed into the device. There might be a holy-volume that gives it enough power without being over-powering but that's pretty much it as far as my guess would be.
 
As for USB cables, I know from a technical standpoint they're not all alike. Some are better shielded (helps with data lose and cable noise) than others. Getting a good quality cable is a pretty good idea but there's no need to go insane, just as with headphone cables there reaches a point where it's just marketing and fluff.

 

[forsberg]

If the USB cable works, then it's fine.

 

[Yoga Flame]

 
Quote:

Does changing the volume level in Itunes change the data flowing from computer to DAC in any way other than volume?
 

 
Moving the volume slider in iTunes will change the data. iTunes will take the digital audio and scale everything down to be softer before sending it to the DAC. It is a lossy conversion, though the loss may not be noticeable. Unless you have a reason to do otherwise, I suggest leaving it at 100% and let the amp handle the volume control in analog.
 
But if you do have a reason, such as channel imbalance when the amp volume knob is too low, then by all means lower the iTunes volume. Channel imbalance is a worse problem than the theoretical loss of resolution from lowering the volume digitally.
 
 
 
Quote:

Is there significant difference using an expensive USB cable to the DAC? ie Is there any data loss with "normal" USB cable?

 
There is a specification that a cable must meet to be considered a proper USB cable. The cable must be shielded, and the two data wires inside must be twisted together separately from the power wires. If a cable meets all the requirements, I'd say that's about as good as it will get. Some expensive boutique USB cables look nice but don't meet the specification. So if you are looking to buy something fancy, at least make sure it is up to spec.
 

 

[mangler]

Good to know, I was just considering buying a "fancy" USB cable, but now I think I'll hold off