I am looking to get a new DAC for my system to replace cheap FIIO DAC that I currently have. Nothing wrong with the FIIO but I have been hit with an upgrade bug. Anyway, the DAC is pulling files from the NAS via Raspberry Pi and converting them into Yamaha A-S2100 amplifier. The amp has a built in pre, phono and headphone amp. I have seen that most of the DACs have volume control and can be used as a headphone amps. Is there a benefit of using DAC as the headphone amp vs feeding signal into the Yamaha and using the big amp to plug the headphones in? I just do not like doubling the volume controls if not needed.