They are actually two different instruments: Martin makes both. The true semi-hollow has steam bent sides like the full hollow body but it is not as deep and has a center block. Both the semi and the full have a Florentine cutaway.
Would need to see some side and back photos to be sure but from what you have posted, it looks like a chambered solid body to me. Given the three knobs, I'm guessing it has under saddle piezo as well as the Citron humbucker (volume, blend, tone).
Either way it's a fine looking instrument, up to Martin's usual standard, and no doubt it sounds as good. Congrats!
BTW I was paying such detailed attention because I have just commissioned a fretless semi-hollow from Martin. I will have a 4-6 month wait before I have it in hand.
It is definitely not a true semi-hollow bodied instrument. It was originally passive and had the under saddle piezo as well as the Citron humbucker. The prior owner removed the piezo and installed an Audere preamp with Volume, Boost/Cut Treble and Boost/Cut Bass controls. I am probably going to reinstall the piezo.
It is definitely not a true semi-hollow bodied instrument. It was originally passive and had the under saddle piezo as well as the Citron humbucker. The prior owner removed the piezo and installed an Audere preamp with Volume, Boost/Cut Treble and Boost/Cut Bass controls. I am probably going to reinstall the piezo.