It would (The block) have to have a selection of pickup types (to be EQ flattened) pre-installed. i.e. single coil neck, single coil bridge, humbucker neck, etc etc. Then the same would apply for choosing the desired pickup type i.e the type you have in your guitar which you wish to use.
Like I say above its not new, the acoustic world has some products which work in a very similar fashion... I have the DTar Mama Bear, and it works like a charm, I run this first in the chain then into a Fishman Aura.... Or direct to anywhere I like..
Here's a picture if you can zoom in, you can see that first you select the "input source" the number corresponds to pickup types (piezo, mic, transducer, electro magnetic) there are 16 types to choose from.
Then he same goes for the "Target Instrument" you choose from 16 different types. and Voila, it does work well actually.
I would imagine with the processing power of the Axe FX something like this would be easy to achieve and do it well - After all it's all about modeling I suppose
and the Axe is the best out there for exactly that. Then different pickups could be added to the user selection as firmware's go on....and on.
I would imagine it would get close, but it's not going to be absolutely spot on... At the very worst it could add some slightly different achievable tones to a single guitar type, and would probably work well enough for those who dont have a single coil guitar for example to get very close with some other slight tweaking.
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