Do comment on this... manipulated/inaccurate/wrongly measured/false/forced data?
@NTK has already provided a lot of information with his post, but I know that some here on the forum consider any information in which the word "Toole" appears to be baised - therefore, a few more details.
First of all, how big are the manufacturing fluctuations in the production of drivers?
These can sometimes be high, as the
measurements from audioexpress.com show with this 250€ woofer from Seas:
As can be seen, the deviations of the resonance frequency in the TSP data for individual driver samples are 10-15%. This is consistent with the data from other manufacturers.
So then let's compare how big the difference is from "freshly unpacked" to "ran the woofer hard for 20h" and give only a few hours of rest (if Danny had rested the woofer for 48h, the TSP data might have changed again).
Here is the TSP data determined by GR-research:
The deviations in the resonance frequency are about 10-15% for the two extreme states (no break-in, full break-in).
What immediately stands out about the GR-research article? Exactly, no frequency response, distortion or waterfall measurements of the driver to show the effects of the different TSP data.
Then let's catch up and simulate the effects of these changes for the driver in a sealed enclosure. First, a sealed enclosure is simulated with the freshly unwrapped driver, and then the same enclosure is simulated with the full break-in driver.
Both frequency response and impedance response simulations are superimposed to make the differences as easy to see as possible:
Nice to see, the TSP data changes have no effect on the frequency response at all and thus do not cause any tonal change.
The article provides zero information on possibly sound-relevant parameters - no measurement on distortion, no measurement on decay, no frequency response measurement.
And the information the article provides shows literally zero tonal impact as the simulation shows.