My 6 year old Samsung Galaxy S4 died last week and getting an unlocked phone seemed like the smart thing to do.
Amazon has good prices on number of former flagship phones that have been superseded by the latest greatest models, but only one manufacturer made any claim to provide better sound. LG says that the V35 has a "32 bit Hi-Fi quad DAC" as well as a choice of 3 filter cut off rates, short, sharp and slow. Also included are DTS-X VIRTUAL SURROUND proccessing and MQA decoding for streaming.
The USB AUDIO PLAYER PRO APP from Google play unlocks the hi-rez DAC's potential and makes direct 24/192 and DSD/DSF file
playback possible bypassing Android system audio limitations.
I am very satisfied with the audio quality I am receiving. I am using KZ ZS7 IEMs with Comply memory foam earphone tips.
The sound is very balanced and the different filter rates effect on playback is very audible. Changing the filter rate to best suit Individual recordings, while heretical, is very satisfying.
Even though I have very limited experience with IEMs and mobile audio, I feel confident in making a recommendation in favor of the LG V35 and the KZ ZS7 IEMs combination based on their sound quality.. The usual disclaimer applies, YMMV!
Scotty
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The LG V35 is also a decent phone but I am not a power user or a gamer. Reviews of both the LGV35 phone and the KS ZS7 IEM can be found online.