A vcom member commented on another forum that Dominants are among the lowest tension strings out there. But I'm not worried about what they sound like...
I have discovered the curious phenomenon that on two different violins, Gewa and Breton, Dominants feel completely different.
On the Breton they feel fine, but on the Gewa they do feel slack. The Gewa is a 4/4.
Both violins were set up by the same luthier, but he did have to reduce the action on the Gewa, and its fingerboard height, to match it to the Breton. Could that have reduced the tension even further? I think I'll go back to Tonicas on the Gewa.
For a given string, the tension is set by the note it is tuned to, AND the vibrating string length, aka VSL (distance from nut to bridge).
Carmen is correct, of course, however, if the string height above the fingerboard is higher on one fiddle the fingers will have to apply more force to move a string to touch the fingerboard and the player may sense this as higher string tension.
Pressing the string to the board changes two things:
I discovered this same phenomenon with my violins. I asked the luthier to set them up exactly the same, same nut height, same bridge height, same string brand. Then they should feel the same to play, yet one fiddle required more effort to press the string down. Of course, it was the fiddle with the deeper fingerboard scoop.