In my personal opinion, I'd say no. The two sound quite similar. The 1840 is a little brighter, and the HD600 has more mid bass - but tonally they are very similar. The Shure would be slightly ahead on imaging. The Senn sounds a little more natural / true to life.
Also the HD600 is more comfortable for me. I found the two ridges on the 1840 headband to sometimes become uncomfortable after a few hours.
If I was ever rebuying though and found both at similar pricing, I'd probably go with the Shure. But given current pricing, the Senn is my choice every time.
How is the "clarity" and "definition" of the HD600 vs Shure SRH 1840?