It's interesting to recall that the Gibson Company made a series of banjos designated "TB" for tenor banjo (the four stringed type) and another line of banjos designated "RB" for regular banjo. (Notice I refrained from saying real. Peter T. would probably jump in and remind us that no banjo can be real.)

The "regular banjos" were all five-string models. Jon of course knows this and is just trying to get a rise out of someone (like me <g>) but I thought there may be newbies to whom the information might be useful. It is, in fact, the four-string model that is the later invention. The tenor model was, I believe, created for the rhythm section of early jazz orchestras and needed the extra volume. I recall reading somewhere that the resonator first appeared on the tenor banjos. I think a lot of the engineering "improvements" we now see in five-string banjos were originally worked out for the tenor models.

      - Mark