Scott, here are some cables I think would work real well for your KP 100S. It was stated by an earlier post that what you could do is get 2 of the cables of course, then use some type of tape, eg., "Electrical Tape", etc., and tape the two cables together with tape every 12" or so. If you get the 4 meter cables (13.12 feet) they would be more than adequate since your Amp will be placed in close proximity to your Keyboard and taping the cables would be a cinch because of the relatively short length. If you feel creative you could wrap the whole cable lengths "except for the 12" or so on each end" with special tape and do it all for under $5 bucks most likely. Here is the link to the Monster Cables I am talking about: http://www.monstercable.com/pro_audio/productPagePro.asp?pin=103

Best regards,
Mike