RE: How does big two stroke engine sounds like ?
Even at a low rpm, two strokes engines sound like two strokes. The characteristic surging idle is still there. A characteristic lack of engine braking also causes them to rev down slowly when the throttle is closed. Also, while four stroke engines get real quiet at part throttle, two stroke engines stay loud at part throttle.
A four stroke engine that revs 20,000 rpm will not be mistaken for a two stroke engine revving 10,000 rpm by anyone who hears it.