Based on early review, it seems like the Mk6 also has one of the highest rated phone speakers on GSMarena based on LUFS output and response, granted you can get more gain if you cup your hands around the phone and it probably boosts the response as well. GSMArena's speaker measurements might not...
Basically do it backwards, Get a flat neutral speaker, connect it to your pc as a microphone (download a mic app), play the sweep into ur phone
How to Test Microphone Frequency Response | TSP (theseasonedpodcaster.com)
So the new XPERIA 1 Mk 6 came out this week, and it looks like Sony claims that theres a new audio circuit that reduces crosstalk allegedly 50% better separation between L&R channels. Hoping it means the power output is better as well cause Amir's model seems to output almost nothing.
I'm...
x65 has quite a good response as well. Has a dip @1.5k which is common for a lot of audiophile (Hifiman,Sennheriser, ZMF, etc...) headphone tuning & Quite flat for the most part and rolloff is fairly smooth and minimal for an open back. I really like my x65.
Composer is quite good too, its...
I mean look at how many folks use ATH-M50x and Beyerdynamic products in pro audio still, none of those products are very ideal tonally for Studio work. While its not perfect I think the x60 is still plenty usable. Frankly I think the Audio Technica R70x has the most ideal response for studio...
Its not uncommon to have projects that are free to share and publicly accessible to be defined as open source, it just means theres an origin point for a product and should be credited if its used and modified