555 dr under the nds?

hello,

i read in different topics that it is not the best to put on the same rack ( fraimlite) the nds and the different ps.  From bottom to top of the fraimlite i have :  nap 300 then 300 dr then 555dr then nds then preamp ( non naim).

Should i put the 555dr on a different rack, and leave an empty space  between the 300dr and nds?   my second rack is a lovan, where sits my sme20 turntable and other components ( ps for the sme20, uptone js2 ps, unitserve)

Is someone didn’t found sound differences between empty space or naim ps under the nds ( or ndx) ?   thanks,   because i don’t know if it is very useful to try that....