How long is too long for interconnects?


I'm looking at upgrading the audio in my photo studio. I have some position limitations due to the lighting gear etc. 

Would it be a bad thing if I put my source and pre-amp up on a shelf and ran interconnects to monoblock amps located at the speakers? The lengths would be about 8 feet to the closest speaker and 12 feet to the furthest; I guess it'd be best to then purchase 2 x 12 foot interconnects, right? 

Any/all thoughts/advice greatly appreciated!
benchwarmer
I recommend longer ICs and shorter speaker cables after much trial and error. The best budget ICs are Blue Jean Cables LC-1. Low capacitance, shielded and cold welded connectors. Buy equal lengths (not custom) and try them. You can return them but I still use them for stereo and HT including 15’ runs. Well built and well priced. 
Yogi is right, the distances the OP is asking about just aren't long enough either way to make much difference.  12 foot ICs are fine, balanced or un...unless he lives near a transmitting tower.  Ditto speaker wires, in almost any case that length won't cause adverse voltage drop or any other loss of signal quality.  Without any other details on the equipment in question, my advice is to do what works best for your situation and enjoy...