shielding question...

[pinkjimiphoton]

hi
was looking at this: http://www.solorb.com/elect/musiccirc/firebottle/

and noticed forrest reccomends a separate power supply with a metal shield to separate it from the circuit to cut down on noise.

is this overkill? or is it a good practice?

would it help with lfo noise, rfi weirdness etc?

or would this only be with this kind of circuit because he's using a voltage tripler circuit, which i'm assuming can whine like a charge pump
does in some cases?

this looked like a kinda cool project... thanks!
on with the endless surfing....