Let's see this 'very accurate' comparative data with proper GRAS measurements then. And importantly, for this specific IEM. Here's analysis by AutoEQ's Jaakko Pasanen of the varying response errors of Crinacle's fake clone RA0045 measurements that people blindly trust relative to Oratory's professional measurements using a genuine GRAS RA0045 for many IEMs (which yes, includes unit variation, but that's unlikely to explain all this variance):
You must think you're clever throwing this graph around but it doesn't show what you hope it shows.
This is the exact same exercise, but this time comparing CSGlinux's database, which uses a GRAS RA0045 coupler, to Oratory's, with the following list of IEMs :
I've tried to eliminate some IEMs for which different configurations are available, and for which I had doubts which one was used, and probably didn't include them all, but I considered different tips and insertion depth fair game since that's also exactly what happened in the original comparison. There's probably a few mistakes in there as well, but so will be the case in Jaakko's comparison, it's to be expected with this approach.
I don't really know how Jaakko's comparison was normalised, so I've gone for two normalisations, one at 500Hz, another one across five octaves centred at 500Hz.
That would be the average difference, using REW :
I'd prefer to know more about how Jaakko performed the calculation for Crin's average difference before directly comparing them, but so far the magnitudes involved are basically similar.
Are the differences for CSGlinux's coupler representative of the actual difference between their RA0045 couplers ? Most likely (hopefully) not. There are just too many variables at play here, and large, bird's eye view database comparisons of this kind are quite likely inappropriate for that task beyond a certain degree.
Performing my own measurements has not only been quite helpful for my own benefit, it's also helped me a lot to learn how to interpret graphs, so maybe you should go on Aliexpress, purchase a clone coupler, and regardless of whether it's a truly good one or not, get some first hand experience by being confronted to all of these variables.
Otherwise next time, perhaps drop the pretend science posturing and make a modicum of effort to actually engage with, read and understand what you yourself quote. There's just too much easily obtainable data graciously provided by many parties out there to be that casual with it and with such an unconstructive attitude.
This may take some time.
