I haven't stayed in this cabin but I assume you are asking: 1) because it is laid out differently and has a stairwell next to it, and 2) because the balcony looks bigger on the deck plan. Correct?
I have read accounts from people who have stayed in the same cabin location on different Carnival ships (those with the same layout as the Valor). They said you couldn't hear noise from the stairs and yes, the balcony is bigger. The cabin layout is also different from the others in that category, and is a tad larger. Again - this is just from reports I have read.