I don't remember which was the actual first regulator in my mouth but my initial training was with both single and double hose (a Calypso and a DA). For 99% of my diving, I still slightly prefer a double hose, even on "tech" dives. About the only time I don't dive a double hose is when I am packing real light.
I think a lot of people first saw a single hose regulator (in the late '60s and early '70s) on "Voyage to the Bottom of the Sea" and thought it was the latest and greatest and had to have one.
I think a lot of people first saw a single hose regulator (in the late '60s and early '70s) on "Voyage to the Bottom of the Sea" and thought it was the latest and greatest and had to have one.