There's nothing nice about this

SEASON ONE DIEGETIC:

In S1:02, Steve opens the door to his house. Raise a Little Hell – Trooper is playing. This is diegetic, because you hear it quieter when Nancy and Barb are talking outside the house, and it picks up in volume when Steve opens the door, implying it’s the music playing in the house. (EDIT: I initially said this was Raise a Little Hell - Toque. The two songs are very similar - so for playlist purposes you can use either.)

In S1:02 when Nancy, Barb, Tommy, Carol, and Steve are beside his pool I Melt With You – Modern English is playing from Steve’s house. This is diegetic.

In S1:03 when Steve and Nancy have sex, Waiting for a Girl Like You – Foreigner is playing in Steve’s room.

In S1:05, Steve sings Old Time Rock & Roll – Bob Seger to Nancy. Obviously, this is diegetic.

In S1:06, when Steve, Tommy, and Carol are driving over to Nancy’s house, Sunglasses at Night – Corey Hart is playing through Steve’s car speakers.

SEASON ONE NON-DIEGETIC:

In S1:01, Steve and Nancy make out on her bed. During this, Africa - Toto plays. This is non-diegetic.

In S1:02 when he and Nancy are making out in his room, Hazy Shade of Winter – Bangles plays. This is non-diegetic, as it transfers into the closing credits song. It is an anachronism. The Bangles didn’t cover this song live until 1983, and it wasn’t released as a recording until 1987.

In S1:06 when Steve and Jonathan fight in the alley Exit – Tangerine Dream plays. This is a soundtrack song and non-diegetic.

SEASON TWO DIEGETIC:  

I debated whether to include this, but In S2:01, Steve and Nancy watch Billy and Max arrive at the school parking lot. Billy is playing Rock You Like a Hurricane – Scorpions at a very loud volume, so Steve would have heard this. It’s diegetic.

In S2:02, the scene where Tommy H mocks Steve about Billy beating his keg stand record at Tina’s party Shout at the Devil – Mötley Cruë is playing throughout Tina’s house. This is diegetic. (This song failed to chart high in the US charts – reaching only 30 on the rock charts. The fact it’s playing at a popular house party, and people are singing along and dancing, implies there’s a relatively big metal scene in Hawkins? I feel like this is supported by Eddie’s band having a venue to play in at all. So, can we please stop pretending Steve would be allergic to metal music lol.)   

In S2:02, when Jonathan arrives at Tina’s party Girls on Film – Duran Duran is playing. This song is diegetic, Steve dances to it. This song continues to play through his breakup with Nancy in the bathroom, and it is still playing when he leaves the party.

In S2:05, while Steve and Dustin are driving to search for D’art, Steve is playing Hammer to Fall – Queen through his car speakers. This is diegetic. (I also want to highlight that this song is categorised as hard rock/heavy metal. Again, please stop saying Steve doesn’t listen to heavy metal.)

In S2:09, when Steve drives Dustin to the Snowball Love is a Battlefield – Pat Benatar is playing.The sound mixing in this whole scene is a little weird, but I believe this is diegetic, and playing through Steve’s car speakers.  

In S2:09, when Steve drives off after looking at Nancy through the Snowball window, Twist of Fate – Olivia Newton-John is playing inside the Snowball. Steve probably could have heard this, and it’s diegetic.

SEASON TWO NON-DIEGETIC:

In S2:01, the scene cuts to Steve and Nancy sitting in his car discussing Steve’s college application letter. Over the top Talking in Your Sleep – The Romantics is playing. This is a soundtrack song and non-diegetic.

In S2:03, when Steve and Billy play basketball together, Go! – Tones on Tail is playing. This is a non-diegetic song.

In S2:04, when Steve and Billy are on the basketball pitch together (again), Scarface (Push it to the Limit) – Paul Engemann is playing. This is a non-diegetic song.

SEASON THREE DIEGETIC:

In S3:01, Steve is in Scoops while Sailor’s Hornpipe – Brian Gulland and Richard Garvey plays. This plays during two separate Scoops Ahoy scenes. It is diegetic.

In S3:01 when we’re introduced to the You Rule/You Suck board, the music shifts from the prev song into Half O’Shanty – Ronald Aspery. This is also diegetic; Scoops Ahoy has a soundtrack of like, jaunty sea music.

In S3:02, Steve and Dustin reunite in Scoops. There is another jaunty, nautical tune playing. I couldn’t find info for the specific song, but this is diegetic. (This happens several other times throughout the series. Scoops has jaunty sea music playing at all times.)

In S3:02, Dustin plays the Russian recording and Daisy Bell (instrumental) - Harry Dacre can be heard in the background. Steve recognises it. Later in the same episode, Steve plays the mechanical horse ride in Starcourt mall, and it plays the same song. These are both diegetic.

In S3:02, Dustin and Steve follow someone who they think is a Russian spy. However, it turns out to be a Jazzercize instructor who plays Wake Me Up Before You Go-Go – Wham! from his boombox. This is diegetic.

In S3:07 Dustin, Erica, Robin and Steve sneak into the Back to the Future screening, Einstein Disintegrated – Alan Silvestri is playing on the screen as part of the movie’s score. This is diegetic.

In S3:07, Robin confesses her feelings for Tammy Thompson to Steve, and Steve sings Total Eclipse of the Heart – Bonnie Tyler to mock Tammy’s singing voice. This is diegetic.

In S3:08, Steve, Erica, Dustin, and Robin are driving to Weathertop. (Your Love Keeps Lifting Me) Higher & Higher – Jackie Wilson plays through the car speakers. This is diegetic.

In S3:08, Dustin and Suzie sing NeverEnding Story – Limahl together. Steve hears. This is diegetic.

SEASON THREE NON-DIEGETIC:

In S3:03 when Dustin and Steve are spying on people in Starcourt, Things Can Only Get Better – Howard Jones plays. I believe this is non-diegetic, however an argument could be made that it’s playing as music throughout the mall.  

In S3:08, Steve, Erica, Dustin, and Robin start to drive to Weathertop, Goldrush – Yello starts playing. I think this is non-diegetic, but it could be argued that it’s playing through TODFTHR’s speakers.

In S3:08, when Robin and Steve are in Family Video asking Keith for a job, When You See Me – Hurricane Express plays in the scene. This is non-diegetic.

SEASON FOUR DIEGETIC:

In S4:01, when Steve drives Robin to Hawkins High Object of My Desire – Starpoint is playing through his car speakers. This is diegetic.

In S4:01, at the pep rally there’s a performance of The Star-Spangled Banner – Tammy Thompson. Both Steve and Robin say she sounds like a muppet. This is diegetic.

In S4:04, while Steve, Lucas, Dustin and Max drive to the cemetery, Hard Feelings – Al Kerbey is playing through Steve’s car speakers. This is diegetic because it cuts off when Steve kills the engine. BUT! IT IS ANOTHER ANACHRONISM! This song didn’t get released until 2017!

In S4:04, Lucas, Dustin and Steve play Running Up That Hill (A Deal With God) – Kate Bush to save Max from her Vecna-vision. This is diegetic.

In S4:07, Eddie hotwires the RV and Up Around the Bend – Credence Clearwater Revival starts playing instantly. This could (arguably) be non-diegetic, but I believe it was playing through the RV’s speakers as a diegetic song.

In S4:07, Steve is driving the RV and talking to Nancy. Fire and Rain – James Taylor is playing through the RV’s speakers. This is diegetic.  

In S4:08, Eddie plays Master of Puppets – Metallica on his guitar in the Upside Down. Steve hears it. This is diegetic.

SEASON FOUR NON-DIEGETIC

In S4:01, when Dustin calls Steve to ask him to play in the Hellfire campaign, Play With Me – Extreme is playing. This is non-diegetic.

In S4:02, while Robin, Max, and Dustin are calling asking after Eddie and Steve is recommending films to customers, Psycho Killer – Talking Heads is playing. This is non-diegetic.

In 4:07, Steve walks into the War Zone. Rock and Roll, Hoochie Hoo – Rick Derringer is playing. This is non-diegetic.

FINAL THOUGHTS:

It surprised me how much more Steve is shown to listen to music in the earlier series. The latter series seem to feature much more OST, rather than using a pre-existing soundtrack.

Overall, when Steve is in control of the music he’s listening to, it’s typically some sub-genre of rock or new-wave. The exception to this is Starpoint’s “Object of My Desire” which is a funk song. He canonically listens to music very frequently; he is almost always shown driving with music playing (I think there’s only one exception to this, and it’s in S4), he’s also shown to have sex with music playing. Although most of the songs he listens to did place in the Billboard charts, none of them topped it – so there’s something to be said for Steve actively seeking the songs themselves out. Furthermore, you never see him play the same song twice, so it can be assumed he has a wide selection of tapes.