The CC51 uses a 6.0mm driver. The Tributes seem to use a 5mm since they say it's the smallest dynamic driver made and the Hisound Golden Crystal is also said to use the smallest driver which is 5mm. If there' an IEM that may use the same driver, that might be it, but the GC seems to have a different signature from what I've been told. A lot of micro drivers look similar in the nozzle.
Edited by Inks - 10/23/11 at 12:04am