The 1.5m cable length is a good guideline. Shorter cables can be problematic depending on the signal risetime. The 1.5m length insures that any jitter causing reflections occur too late to have any impact. Really short, say 6 inches can also be good, but between 1 foot and 1.5m, you are taking a risk IMO. Dont spare the change.
Adapters do make a difference, but again depending on the signal risetime. The faster the risetime, the better the jitter result. Here are some plots showing jitter with different cables and adapters:
http://www.audioasylum.com/forums/pcaudio/messages/13/132743.html
I have been doing this a LONG time and I know what I'm talking about.
Steve N.
Empirical Audio
Adapters do make a difference, but again depending on the signal risetime. The faster the risetime, the better the jitter result. Here are some plots showing jitter with different cables and adapters:
http://www.audioasylum.com/forums/pcaudio/messages/13/132743.html
I have been doing this a LONG time and I know what I'm talking about.
Steve N.
Empirical Audio