How important are speaker cables to the sound emanating from the speakers?

I have found that speaker cables are critically important to the sound emanating from my speakers. Whenever I have tried to run my system without speaker cables, the sound was non-existent. ;^)

Legacy recommends Morrow cable, and uses Morrow SP7, $1499 a pair, at audio shows. Clearly, while Dudleston might view cables as the the least important part of the playback chain ( and I agree ) he nonetheless finds speakers cables to be very important...

I don't look to professional studio personnel and technicians to know how to set up a fine home audio system. I advise not to listen to them. 
Even the venerated Alan Parsons showed his gross ignorance in this respect, as I commented on years ago. 

Bill Dudleston  at my request  upgraded my Legacy Whisper DSW speakers to "Clarity Edition" as an experiment regarding efficacy of internal speaker wiring. You can read about that also at Dagogo.com. In brief, he also suggested a caps change to Clarity Caps (no relation to Clarity Cables). He wasn't expecting much, but was impressed by a measured 2dB improvement in the bass. Some would suggest neither the caps nor the cables should have made a change. It did, measurably.  :) 

For any naysayers who think that speaker cabling does not have a profound effect on the sound quality of a system, I would recommend trying different brands in ones own system.

 I have found speaker cabling offers a huge increase in quality of sound. If you ever have a chance to listen to Klee Acoustics speaker cabling,please do so...you will be astonished by the overall improvement to your listening experience. Highly-recommended.