Thank you for your suggestion.   I have that feeling, I must turn up the volume to get a better experience, and I have he sensation that some sounds are distorsioned when I do that (for example, the piano in classic music).... I never try a dedicatd amplification so I cannot know if this is...

Hello; (First of all, sorry for my English)   II have a Marantz 1504 AV receiver and I use it to play FLAC from my NAS server.   I never heard how sounds a dedicated amplification for headphones, It´s a big diference? The Headphone output of a Reveiver It´s a crap? I would use it to amplify...