Long Speaker Cables with Tube Amps? Bass Response

There is a gorgeous, well reviewed Tube integrated that I am interested in getting, but my home system setup requires that I use speaker runs of approximately 15'. It has always been my experience that shorter speaker runs produce superior results with tube amps, most notably in the bass, presumably due to greater damping factor. Does anyone have experience with Tube amps and long speaker runs? I am using Synergistic Research Designer Reference FX interconnects and Alpha Quad Active speaker cables. The integrated in question is the Cayin SA 88T / KT 88. Thanks for any insights.
I have used Cardas SE-15 in 8' lengths with my SET's and now their SE-11 in a 16' lenght and don't think I lost much if any. They also make an SE-9 which is 9 guage if you'd feel better about the extra copper. Good luck.
Arn't all amps well reviewed.
That's funny and true. The Cayin sure is pretty though.
Anacrusis, if you're using SR cables, I doubt you have anything to worry about, since they are pretty evenly balanced both from a sonic standpoint, and electrically.
I'm currently running a Blue Circle BC6. Its a 25 watt tube amp and I'm using Virtual Dynamics Master Series 10' speaker cables. The BC6 recently replaced a 125 watt SS amp and trust me, bass response is not a problem. The BC-6's lower end is deep, powerful, dynamic and detailed with these cables.