Hmmm...perhaps I should quit making ambient, then. My Digisound 80 has none of those...so none of my 15+ albums of ambient work are valid anymore.
(NB: the equipment doesn't make the music. The artist does. Believing that certain pieces of equipment are "necessities" is an utter fallacy, and a great way to kill ones' creativity by becoming reliant on specific musical "crutches". If you can make incredible ambient music with a couple of steel drums, a touch of reverb and multitracking with no other electronics at all (see Stephan Micus' work for this example), then do so. But if you have to labor under the misapprehension that you MUST have X piece of gear to do Y sort of music, then quit immediately, as you're not really making something that truly speaks of who you are musically.)