Buddy of mine did some research on what what phone have the best audio quality and found that these are the best audio chips you can get for a smart phone:
Wolfson, which supplies audio chips in a vast array of smartphones and tablets along with HiFi equipment, has announced its first quad-core audio system-on-chip (SoC) dubbed the WM5110. The firm claims that the chip has a 110dB signal-to-noise ratio and the four cores clocked at 150MHz offer 600 MIPS of processing power using just 3mW power.
The firm's WM5102 provides a respectable signal-to-noise ratio of 102dB and has 50 MIPS of processing power. Wolfson claims the WM5102 not only is physically smaller than its rivals but uses fewer parts, meaning device manufacturers can reduce the size of the circuit board and the bill of materials (BOM).
The TFA9887 optimizes the audio signal based on the movement of the speaker, something no other system is capable of, using the full capabilities of the speaker without pushing beyond the limits. An advanced clip avoidance algorithm monitors audio performance and prevents clipping, even when the power supply begins to sag. Bandwidth extension increases the low frequency response well below speaker resonance.”
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