Im not an expert on cymbals like many posters here, but are they similar in sound, or completely different?...Im curious why the hollow ink, as if there was an attempt to bring back the stamp vibe?
Let's not confuse the ink stamp and the engraved trademark. These are late 70's/Early 80's "Hollow Ink" Stamp. It just means the Zildjian Ink logo printed on the bottom of the cymbal was "hollow", ie not colored in, only outlined. The top of the cymbal had a "normal" trademark/engraved stamp and just the model (Splash, Thin Crash, Medium Ride etc.) stamped in ink, but no size designation was given.
The "Hollow Stamp" refers to cymbals from the 50's with a large Zildjian word-mark in the engraved trademark that is block letters that are much thicker than normal (shown above). There is no ink stamped on these cymbals.
In most conversations, the term "Hollow Logo" or "Hollow Ink" refers to the ink on the cymbals; "Hollow Stamp" refers to the engraved trademark.
I hope that helps clear it up.
V