We recommend that you run your headphones in, because it really does make a difference. This affects the moving components like the coil and the membrane. The latter is particularly affected when the membrane is coated, especially when coated with titanium. The components get “run in”, the plastic (Mylar) membrane becomes more flexible, the internal stress in the material and between the membrane and the coating reduces. All components play and work better together. We cannot provide explicit physical evidence for this, but years of experience shows that the sound develops positively. The extent of this varies and is not the same for every converter or headphones. The high frequencies lose their sharp points, the bass becomes more precise and the overall sound gets more round and harmonious.
Running in therefore definitely improves the sound, but the basic characteristics of the headphones remain fundamentally unchanged. When trying to analyse sound, “human” factors (such as familiarisation, mood, etc.) also play a role and should by no means be underestimated.
In conclusion it can be observed that there is no definitive proof, and that is why there will always be two camps, proponents and naysayers, when it comes to running in.