I was thinking the same thing. The later, wider ones have more mass further out from center as well as more wood to help dampen resonance. That switch to jarrah though, made for a less attractive appearance but if it improves sound quality, I shouldn’t fuss..
With the maple Opus3, they just left it chunky all the way back..
Anyway, what prompted my questions about their wood selection was because I just picked up another “Reference Platinum” with the old body style - but in what appears to be jarrah, unlike my other one made from mahogany…
I think this one’s jarrah which looks much more porous than mahogany :
View attachment 3001232
…and I think this one’s mahogany :
View attachment 3001239
I haven’t compared them yet. When I bought ‘em, my intention was to have ‘em both re-tipped with a much nicer needle profile and possibly a boron cantilever too. I’ll have to put them under the microscope first; they’re both supposedly very low hours…
BTW - looking at the spec. sheets and Grado’s site, the old mahogany bodies weigh 6 grams, jarrah with that style body weighs 7 grams, Opus3 weighs 8 grams - and the current jarrah bodies weigh in at 9 to 10 grams, depending on model..!
SO… I think it may be unwise to assume that all Grado woodies require the same tonearm mass (?).