whats the difference?

Not positive, but I have two guesses. One is that the the T suffix means "treble" and thus the pickup is brighter. That would mean that the B suffix is for "bass", meaning that it's deeper. I think that all Bartolinis are available in these two "flavours".

The other guess would be that the suffix indicates what position the pickup should be installed--B at the neck and T at the bridge.

 

I'm pretty sure it's the latter definition. T = bridge pickup, B = neck pickup. I don't know if they're voiced differently or just slightly different sizes.

 

M44CT....T=Bridge pickup, M4=pickup style, 4=number of strings, C=deep tone. The M44CB is the same pickup at the neck position (B=Neck pickup).

 

geshel is right.. since Pickups are sold separately usually. they sell them by "Bridge" and "Neck"

Example
Seymour Duncan Active Soapbars(My favorite )

ASB-5n = neck
ASB-5b = bridge
ASB-5s = Set (Both Neck + Bridge)

 

"T" and "B" might also have another implication. My P46s are quad-coils (Which, from the Bart literature, the M44Cs might be - they list both the dual and the quad-coils as 'C'). The bridge pickup is wired so that the two coils (each a split humbucker) available are the "neck" and "Bridge" pairs. The neck pickup is wired so the two are "P" and "reverse P".

I'm not sure if these connections are done internally, or somewhere in the wire upstream of my control cavity. Probably internally. Eight wires per pickup would be a bitch.

BTW, the catalog at www.bartolini.net is a pretty good reference for the model names and numbers. There are some confusing bits (like how a 72P46x is dual coil, but xxP46x is quad coil?).