I just bought a second Favilla Baritone - no SN; no label; Favilla impression inside....it's different than the one with the SN; it's got a smaller bridge, slightly smaller lower bout, inlay around the sound hole is different....no SN is b-w-b-w and the SN is w-b-w....the no SN seems to ring and resonate more and it's got old strings - the SN has new strings I put on....I'm thinking the no SN is older, but I'm not sure if it's possible to determine how much older....maybe by the smaller dimensions...both are 19"....friction tuners. Any help with aging would be appeciated, however, I did sent Tom Favilla a note....