Speaker cable length

I think these are too long. I put my power amp between the 2 speakers and run a 6 feet length of speaker wire to the speakers. The interconnect from my preamp to amp is about 16 feet...works fine. In any case, I would have equal lengths of wire for both speakers.

I also have a similar set up, but keep shorter speaker cables (6)', amp resides between speakers, and running longer ICs( 15') from amp to source.
Hope this helps.

Problem is that between where my speakers should be positioned for best listening is a large floor to ceiling window so putting my amp between speakers wouldn't work.

Depends on the cables and amp.

At CES in January 2007, AJ Conti of Basis Audio ran a pair of speakers with his cables. One speaker was wired with a 6' pair and the other speaker was wired with a 75' pair.

Not a single listener could discern the difference.

Go figure.

Your biggest enemy with long speaker runs is resistance, so if you're stuck with 27' runs, go for the heaviest gauge cable you can find (and is practical).

If you're concerned about the different lengths (27' versus 18'), then just use two 27 foot lengths and hide the extra few feet of cable behind your amp or speaker (but don't coil it up).
That said, at the speed the signal travels through the cables, you're unlikely to hear any difference at all even if you use different lengths of cable.