These headphones have 2 drivers in it. One 55 mm for bass and a 30mm for mids and highs.
Below a plot measured by ultrabike (Changstar) with a flatbed DIY rig.
some background on these... ermm ... transducer thingies .... you can put on your head that appear to be a luxurious item.
The “Real Sound System” delivering both the realistic deep bass sound as well as the mid to high sounds with high degree of resolutions.
uk.jvc.com
These are called 'the real sound series'... In an alternate reality perhaps.
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