I have both, technicalities wise it’s an upgrade. Tuning wise they sound day and night. AS12 is KZ V-shape house sound, AST is dark warm signature. If you like bright and impactful, you may need to reconsider AST, it may disappoint you.Should I jump on the AST hype train? Already have AS12.
Imagine AS12 is sparrow’s chirps and AST is night owl’s hooting.
Basically that describes the characteristics.