Not a spec calculator — a bluntness calculator. Enter what you already own and what you are eyeing next, and see roughly how much of the theoretical ceiling each purchase actually buys, based on the diminishing-returns pattern described above. This is an opinionated model, not a lab measurement — a gut-check, not gospel.
The model assumes quality climbs fast at first and then flattens — the same pattern described above, where roughly $500–800 buys around 90% of what any amount of money can get in headphone audio. It never reaches 100%, because in this hobby nothing ever fully does. The percentage is a deliberately simple illustration of a real pattern, not a measurement of any specific product.