PTR Advantages - Rapid Spectral Decay

Nothing ever stops happening instantly. One measure of a loudspeaker's quality is how fast it quiets down after its input stops, like the braking distance for an automobile. In this graph you can see that in an ordinary loudspeaker cabinet, the sound dies away slowly; the curve is still high off the floor at the end (front of graph). This means that drumbeats, spoken consonants, and similar brief sounds are not as "crisp" as they should be, in ordinary speakers.

But look at this measurement performed on the same drivers in an PTR cabinet! You can see that the "quieting down" is much faster in an PTR-enclosed loudspeaker. Short sounds stay short. Crisp accents and drumbeats stay crisp. All by changing the shape that the air is vibrating inside.