There is something I always had, but then I realized now it is also affecting languages:
First, I do not have perfect pitch, but I can recognize the common intervals if I pay attention. And, my last hearing test showed good numbers for my age (48) with a slight attenuation over 4k on one ear.
For some reason I have a much better ease at recognizing the intervals in the higher pitches than the lower ones and I'm trying to understand why.
It doesn't seem logical to me since intervals with low notes will most likely have harmonics going through most of the hearing range, whereas the higher pitches will have less audible components to them. I guess the higher notes have more space between them, frequency wise, so it could be a factor.
As far as instruments, I started playing Organ then Piano when I was quite young, then electric guitar and I picked up the bass on the way (but I play bass like a guitarist :)) Somehow with the bass, I just can't pick up the intervals well from the low E to ~C, but after that it gets better. With the piano, I have difficulty on the first 3 octaves. On the guitar, it's generally ok.
The reason I'm asking is also because I realized I have exactly the same thing happening with languages! I posted this question in the linguistics site: https://linguistics.stackexchange.com/questions/38378/easier-to-understand-some-foreign-languages-with-a-higher-pitch Where I describe that for languages I can understand, but I'm not fluent with, I have more ease understanding female voices than male ones.
So there seems to be a phenomenon where the higher register is somehow easier to 'decode', at least for me.
I'd like to know if this is something common, and if there is a known explanation for it.