Ryder,
You can get that info from PMC site, or do a search on the net, there is plenty of info on PMC.
OB1, IB1 and EB1 all have Vifa midrange driver.
The only difference between OB1 and EB1 is LF driver, cabinet and of course cross-over.
In-house made PMC driver is used in IB2, MB2 and higher models.
Just find good resolution pictures of EB1 and IB2, or visit PMC dealer, and you will see glaringly different midrange drivers.
I owned PMC speakers including IB2, and the reason for IB2 was the midrange driver, so I should know.
You can get that info from PMC site, or do a search on the net, there is plenty of info on PMC.
OB1, IB1 and EB1 all have Vifa midrange driver.
The only difference between OB1 and EB1 is LF driver, cabinet and of course cross-over.
In-house made PMC driver is used in IB2, MB2 and higher models.
Just find good resolution pictures of EB1 and IB2, or visit PMC dealer, and you will see glaringly different midrange drivers.
I owned PMC speakers including IB2, and the reason for IB2 was the midrange driver, so I should know.