Will a 30 feet long speaker cable cause problems?

My B&W 602S3 bookshelf speakers are located 30 feet away from a Rotel RSX-1055. Will this distance cause any degradation? Also what gauge speaker cables are recommended for such lengths?

I am a reviewer so I am going to respond to you privately. Extra long speaker cable lengths have the potential to cause problems, such as roll-offs in the low bass and high treble. Also, speaker cables with unusually high capacitance may not be especially friendly to your amplifiers given a 30 foot length. Thus, I would not opt for a some of the fancy (and expensive) cables that manipulate the capacitance, inductance and resistance in order to ostensibly "tune" their product to a given amplifier by influencing the frequency response of the amplifier. My suggestion is to use as THICK a cable as possible (at least 12 gauge and perhaps even 8 or 10 gauge) to maintain as flat a response as possible. Best of luck.
Go over to Audio Asylum, click on the FAQ page, then find Jon Risch's website. His DIY 89259 cross connect speaker cables have a design that lowers inductance, which is what you want for long speaker cable runs, while keeping relatively low capacitance at the same time. End result is it minimizes rolloff's over distance. It also is fairly inexpensive, being a DIY project.

30' will not sound as good as 10' of the same cable.
At 30' even using the highest quality speaker cables you are going to get roll off at frequency extremes.

Using lesser quality speaker cables, you will get even more roll off.

I would suggest trying if there is any way you can to shorten the speaker cable run. If you are stuck at 30', you will just have to live with some roll off.