The pinks definitely get their name from the cloth, not the driver. The cloth itself makes no difference to the sound. It is an indicator of when the driver was made though.
Yours look like a proper pair of pinks in the pictures.
Early Grados have been noted as having a slightly different sound signature compared to later Grados. Finding a pair of pinks means finding drivers from another sound signature period in the company's history.
My experience is limited to the SR series of the Grado line, both pinks and latter-day versions. I can attest to the pinks (at least the SR225 I had, and the SR80 I currently use) having a smoother, less aggressive sound. I also hear better layering in my SR80. They are not as detailed as a modern pair of SR225i, but, its not by much.
Check for other indicators of date of manufacture on your headphones:
1. What model are they? Check out the Grado history thread for years when certain models were introduced.
2. What does the headband look like? The thin, plastic headband was introduced later, earlier SR models had a more substantial but still pleather one.
3. What do the gimbals look like? Do they have a bump at the apex or not?
4. What does the cable look like? Early SR models were released with the same cable as the higher end models and a quarter-inch jack as opposed to an eighth-inch one.
The joy (and for some frustration) of Grados is all of these variations, both cosmetic and in sound signature. To paraphrase a fellow head-fier though, don't forget to use them for their primary purpose...enjoying music :).
Edited by fleasbaby - 11/15/13 at 5:28am