15 Aug
2014
15 Aug
'14
3:36 p.m.
On Aug 15, 2014, at 5:15 PM, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
Perhaps some audiophool could tell me why domestic
audio equipment never
has balanced inputs and outputs. Now that, by eliminating problems from
ground noise, could make a real differnece. But that's engineering, not
snake oil, I guess.
I've actually wondered that myself. THAT is something that could improve
signal quality, especially with the manifold sources of EMI wandering
around all the time these days. My home recording setup is fully
differential to the FireWire audio box and out of it to the amp for the
speakers; one could think of speaker connections as differential as well,
given that common mode noise should cancel out.
Of course, all our modern digital cabling (HDMI/DVI, USB, Firewire, and
probably a few more with the notable exception of S/PDIF) is fully
differential these days. Some of that has to do with common mode noise,
and some of it has to do with "current-steering" logic drivers, which
can achieve a much higher speed with the same transistors.
But in general, unless I know there's a reason for a high cable price
(exceptional craftsmanship for cables that are going to take a lot of
abuse, for example), I get suspicious if I'm paying more than about $10
a cable. That's especially true for digital cabling like HDMI, where
there is no subtle performance degradation; if the signal is bad, it's
pretty obvious. I wish I were ruthless enough to make money charging
$75 for 3 feet of differential cabling, though.
- Dave