Catless dp + secondary cat placement?

[feral107]

I have a catless DP installed but the smell is really getting to me.
Decided to install a high-flow universal cat after the dp, but don't know where to place it.
I'm a complete noob so bear with me.

1. Would getting a highflow secondary cat negate the performance and sound benefits of my DP? What if I placed the secondary cat further away from the downpipe?

2. Would placing the secondary cat too far down the line affect its functionality?
(i want it further away to protect it from future burble tunes)

[feral107]

do cats require heat to function?