I just received the amp and have let it get up to room temperature before giving it a whirl...
First impression is of a very high quality piece of hardware - It looks very classy and fits almost perfectly under my iPhone5 (with slim case).
I have a question though - The 0dB gain position... Does that do what it says on the tin, ie doesn't actually amplify the incoming signal? I'm confused!
With the switch in the 0dB position, the output is no louder than it is from the headphone socket of my iPhone (which I'm feeding the amp from).
Obviously switching to the 16dB position amplifies the sound significantly, but I don't understand the purpose of the 0dB position if it's not actually amplifying the source - Doesn't that just make it an expensive attenuator (unless it's at full volume)?
I realise that volume isn't everything, but clearly I'm missing something!
0dB gain means the output=input when the volume set to max. it is designed for high sensitivity IEMs.