amp EQ range and EQ pedals

[JDC]

I've told myself I can't buy my ENGL until I find a new job but I got wondering, what's the dba range of the EQ controls because:

if I have the amp EQ set to 10/2/8 for rhythm and I want to use an EQ of say  10/8/2 for leads plus a little boost, is an EQ pedal going to give me enough range to make such a change?

I know the MXR EQ pedals are +12 to -12 and the boss pedal is +15 to -15

[gwEm]

i know my marshall jmp50 master volume is very sensitive to even small adjustments of 3db or so with eq pedals.