RCA cables from preamp to amplifier

Just beginning to tool around with seperating my equipment and component rack from in between the spkrs. I've wanted to do it the cheapest way possible (in my eyes) just to see what happens. As you see my system has straightwire rhapsody's (6ft) which I've had for at least 8yrs and no other type. The cables that were just purchased so that I can place everything minus the amplifier behind the listening chair are 25ft Comprehensive XHD for less than fifty dollars a pair brand new. Does anyone know if sound will suffer? I know it's said in all advice to keep cable lengths as short as possible.
My gut impression says, “yes”, not good for the sound. That just may be too long a run with suspect wires.

You may want to save up. Also, with that distance you should really consider XLR (balanced) cables.

Enjoy the journey,

The balanced cable suggestion by Jb8312 is a good solution, if you have noise problems. I will add that if you don't have balanced input and/or output connectors on the units, take a look at using an isolation transformer(s) along with the balanced cables to get the CMRR.
Thanks for the suggestions all unfortunately I dont think that upgrading the preamp to something with balanced outs will work budget wise. I think that the TL 2.5 totally kicks with all sorts of music which is a good thing for the wide variety of music that I enjoy. After spending a few hrs the other day when I first plugged them in and then about 4+ hrs last night listening I think that they need to be allowed further break-in.(sounds just a wee bit congested on some symbols) I played the system all night to get things cooking a little faster! I do notice a difference from the shorter straightwire however nothing major like when I changed the spkr cables. Being that I just plugged them in and still havent moved my gear around they are just coiled in front of the equipment rack in between the speakers but am close to installing for good.
Well after playing more of the music collection I've come to realize the importance of keeping the lengths short. Sounded terrible lacking dynamics, punch, and more i'm sure that I cannot think up a term to describe. Plugged back in the originals and life is good again!