30 runs of balanced interconnect

Hi, I have to run 30' of interconnect (balanced) between amp (Levinson 335) and preamp (I am still choosing one). Will I incurr a serious performance issue due to the length of the connection. Also, do box cables really make a difference
Balanced connections are used professionally due to their ability to be used for long runs.
I running 20ft balanced runs. With your level of equip it not a problem. I'm using transparent cable, big difference from cardas. Can't say if it's the boxes or something else...
That's exactly what I run without any problems. Even works with unbalanced lines.
As far as professional use goes...I think balanced cable can be run up to 1000 feet, which is why they use it.
I have been using Jeff Smith's Silversmith interconnects and they will take a 30 foot run without any problems. His site is http://www.silversmithaudio.com/