FiIO Q1 vs E18

[Book]

I wanted to ask which one would have better performance when paired with S7, assuming i am using OTG dac included with both models.

[GaNi]

It completely comes down to what type of cans you would want it to drive. I own both since Q1 has half the power of E18 (32Ω@190mW vs 32Ω@306mW). I use JVC's SZ2000 along with E18, it is just enough to drive these cans though they're just rated at 16Ω it's how the drivers are designed(50MM+30MM). I am pretty much happy with E18 since it's packed with a huge 3500mAh battery and can also charge your phone (Nexus 6P).

 

[Book]

What about the sound quality is there any difference? Since there is a DAC in both units, so i wnated to know is it any different. 

[GaNi]

With the E18, it sounded more warm and punchy. I am a bass oriented guy so I normally have EQ V-shaped. On paper both have a good a DAC from Texas Instruments ( http://www.ti.com/product/PCM1798 E18 and http://www.ti.com/product/PCM5102 Q1) and similar playback formats. If I were to say, I would go for Q1 if you're looking for something small and gets the job done. But E18 if you want to drive power hungry cans and want a longer battery life.