There is measurable loss with extra long speaker cables and if it is measurable it is audible. It depends on the gauge of the cable and the speaker's impedance. There is more loss with lower impedance speakers. For example, if you are running Apogee Scintillas with 16 gauge wire your maximum run should not exceed 6ft. However, if you are running Klipschorns with the same 16 gauge wire 50 ft is ok.
long speaker cables or IC's for budget system
I am planning to rearrange my room so that my stereo rack is in the back corner of my room instead of between the speakers. The issue this creates for me is which cables to switch out. I could leave the amp between the speakers and run a 25ft pair of IC's from the amp to pre-amp or move the amp back to and run a 30ft pair of speaker cables from the amp to speakers. I currently have MIT T2 interconnects between my amp and preamp (1meter) and have 8ft MIT T3 speaker cables. The problem is I am only giving myself a $150 budget which has me looking at Blue Jeans cables. Am I hurting the sound quality of my system by downgrading cables? Please take a look at my system to see a list of my components. The only upgrades that I plan to make in the next couple of years would be switching from 1c's to Vandersteen 2Ce Sigs and maybe upgrading the turntable as well. Please factor in my future upgrades with your suggestions. Thanks in advance for the input.