Why isolation matters

I mentioned in yesterday's post about a new USB isolation device called the LANRover. It dramatically improves USB audio performance by fulling isolating the computer from the DAC, regenerating the audio into a new form before rebuilding back into USB. But why does isolation between products matter? And what are the downsides to improving isolation? In a perfect world one thing would not affect another, but that isn't how nature works. When we dam up a river to generate free electricity there's a penalty to be paid. The dam affects the river. There is no way to effectively isolate the two and remove the interaction. If we could, then the electricity generated would be truly free, which of course, it is not. There's a penalty to be paid. When we connect two pieces of gear together we want one to affect the other in one sense, and not another. Connecting a computer to a DAC is the only way to transfer music stored on the computer to play on the DAC. The two must interact in order to work. But, like the river/dam example, we're always transferring more than what we want. What we want is just the musical information. What we get is music, noise, and jitter. The consequences of this added baggage is poorer sound quality. When we insert a product like the LANRover between the two we keep the music intact and significantly reduce the unwanted noise and jitter from the computer. But it too comes at a price: more stuff in the signal path–which isn't always a bad thing as we've seen when inserting a preamp between a DAC and the power amp. But, there's always a cost to everything we do. Let's spend some time looking at interactions over the next few days and see what we can learn.