I can recognize some accordions, but there are just too many to be able to identify all of them. A term like "an older Hohner accordion" does not refer to a specific sound because for instance a Hohner Atlantic from 1965 sounds very different from a Hohner Gola from 1965... Sound is very model specific. But sometimes differences are subtle. When you put a Hohner Morino IV M, IV N and IV S next to each other you may be able to distinguish all three, but when you just hear one it's easy to tell whether it's a IV M or one of the other two, but the IV N and IV S sound quite similar to each other (the main difference is Bugari TAM reeds in the N and Cagnoni TAM reeds in the S). With the IV M it's very hard to hear the difference between the older ones with Hohner TAM reeds and later ones with Bugari TAM reeds... Likewise for instance, a Bugari Champion cassotto and a Bugari Artist cassotto sound similar, but when you hear them side by side you can hear the difference. Of course the difference with a Championfisa (no cassotto) is much larger...
When you hear similar accordion models from different brands it becomes interesting to try to identify them. A Pigini, Bugari, Victoria... all have a different characteristic sound.
As some of you know I regularly make recordings of my arrangements for accordion ensembles and post them on YouTube. For each recording I choose which accordion to use for which voice. I have mainly three different sounds available: AKKO bayan, Hohner Morino (S) and Bugari Artist Cassotto (of which I have two). When I hear just a few notes on the M register (clarinet) I can easily identify which of these three accordions is played. Each arrangement requires a different sound... so I consider myself fortunate to have such a range of sounds available.