[LeDave]

Hi, I am a noobie audiophile with a decent set-up. I can't find any difference between low gain and high gain on my Sony PHA-1 DAC/AMP. The only difference is high gain increases the volume. Is high gain suppose to just turn up the volume? If I set to low gain, I will have to increase the volume and it'll sound like high gain without changing the volume in the first place. My source is a iPhone 6.

 

[billybob_jcv]

Yup - pretty much.

Gain is the amount of voltage increase the amp supplies between the input signal and the output signal. If you have difficult to drive headphones, then you might need a higher gain to make the headphones sound the best during music that requires more amp power. If your headphones are not difficult to drive, then all it is going to do is increase the volume. There *might* be some benefit to only using high gain if you really need it, because the higher gain is applied to BOTH the music and any noise that is on the input signal to the amp. However, this might be a difference this is completely inaudible, and therefore irrelevant.