Here are some of my favourite "headphone" songs that I use as go to, or just to thoroughly engulf myself into music after a long day. Of course everyone's preference will be different
BB. King & Eric Clapton - Marry You
Bobby Womack - Nobody Wants You When You're Down And Out
Childish Gambino - Sweatpants
Childish Gambino - Heartbeats
The Seatbelts -
Gotta Knock a Little Harder (from the Cowboy Bebop OST)
Yoko Kanno -
Don't Bother None (from the Cowboy Bebop OST)
Daft Punk - Give Life Back To Music
Anthony Hamilton & Elayna Boynton - Freedom (from the Django Unchained OST)
Doug MacLeod - The Night Of The Devil's Road (a quiet track that builds up, superb with the volume up!)
Duke Ellington - The Swinger's Jump (sweet sweet Jazz
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)
Fat Freddy's Drop - Blackbird
Fever Ray - If I Had A Heart (the opening theme to Vikings)
Fever Ray - Concrete Walls
Flight of the Conchords - The Most Beautiful Girl
If you find you like most of those then I have many more favourites i could share. If not then ignore the above lol.