Dear Friends,
The actual reproduction of this design is not important, it more 'how to' tackle something I first thought was very easy but still can not find a good way to reproduce.
Basically I can see 4 vector wavy lines each with a gradient falling away on one side that is consistent whether the line is rising or falling. Interaction between the lines can be taken care of by overlays or whatever, its really the process forming a line by either using gradients that follow the line or create a brush that will do the job.
The concept can then be used on backgrounds, letterheads etc
This is probably something I will kick myself about but at present I am baffled.
Thanks for all your help,
Graham