Isospeed Control vs Isospeed Control Classic


I played one of my k90s with Isospeed Control Classic at 62 lbs. for a couple weeks and then bought another strung with Isospeed Control at the same tension. I just hit with the reformulated string tonight and the feeling seemed a little different; not bad, just different. Any ideas here? Did they really change the string that much, and what is the different in makeup that would account for the (almost radical) difference? Any help would be appreciated. I thought I finally found my ideal string/racquet combination and now I'm almost back where I started with trying to find the right string.

Just for the record, I realize that the tension loss in the k90 strung with Control Classic over two weeks softened the string bed and decreased control and may account for some of the difference I'm feeling in the new string job. But, I'm confident that is not all of it. Again, I appreciate any thoughts on the matter.
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New User
I believe that the ISO Control Classic series are to be strung at a 10% higher tension than the newer Control strings for the same affect.

Here's an excerpt from another thread:

The Professional Classic is recommended to be pre-stretched and the tension adjusted about 10%. The new Professional does not require a pre-stretch or tesnsion adjustment as it features pre-stretched filaments inside the string.

So pre-stretch Professional Classic and adjust the tension 10%.
String the new Professional at your regular tension and don't pre-stretch.

The above also applies to Control Classic and the new Control.

Chris, TW