Aside from signposting the emotional settings and requirements of the scenes they share and follow, the tracks act alongside the ridiculously sharp attention to the detail the show has to forge a nostalgic connection with each season's historically important years. Much like the Kodak Carousel - which projects an idyllic past and the connected memories and emotions tied to each photo – the soundtrack is the show's own Nostalgia Jukebox Carousel – allowing Weiner and co. to emotionally ground scenes in an imagined past much of the viewership associates with the iconic songs used (thankfully we don't need spare change for this one).

An important factor in all of this is the creator's intimate relationship to the tracks we hear in the show. Weiner says he chooses "almost every piece of music on the series" and even had songs in mind for Mad Men before the show even existed; though he also works with music supervisor Alexandra Patsavas, whose other work includes The OC.

Of course every major or minor television show, from Boardwalk Empire to Made in Chelsea, makes use of songs in this way but Mad Men's historical allusions and dedication to a supposed authenticity of the past make it somewhat special in what it chooses to entertain our ears with. The selection signposts events and their impact, allowing the viewer to slip into the mindset of the characters facing 1960s America.

Not only that, but the music enables the show to tap into a larger cultural landscape beyond the one we experience onscreen - from the LSD experimentation of The Beatles' "Tomorrow Never Knows" via Leary, Metzner and Alpert's The Psychedelic Experience: A Manual Based on the Tibetan Book of the Dead (taking us beyond what we see in Roger's escapades), to The Crystals' (Carole King's) hauntingly brutal Phil Spector-produced piece on spousal abuse "He Hit Me (and It Felt like a Kiss)", (the title apparently the exact words Little Eva gave Caroline King) curtailing an episode which references the Richard Speck murders and features Don hallucinating murdering his lover;  and the death of America's sweethearts Marilyn Monroe with her Some Like It Hot hit "I'm Through With Love" and JFK with Skeeter Davis' "End of the World".

A few tracks may have snapped the viewer out of their immersion - namely more recent numbers such as The Cardigans' "Great Divide" and The Decemberists' "The Infanta", used in the first and second series, respectively. The Swedish group's 1996 track doesn't seem to out of place, with its playful lyrics and strings, but the Portland outfit's abrasively catchy guitar doesn't quite mesh, though its lyrics are pulled from age far earlier than the 60s.

The show isn't just content with featuring background songs, it also features actual performances, with everything from Colin Hanks singing Peter, Paul &  Mary's biblical folk hit "Early in the Morning" to Bert Cooper's "Best Things in Life are Free" and Megan's birthday serenading of Don with Yé-yé pop classic, "Zou Bisou Bisou". This track kick-started series five and proved so popular it was even released on iTunes and a limited 7" Vinyl - plus actress Jessica Paré was even invited to go on tour with Jesus and the Mary Chain.

Don's facial expression at "Zou Bisou Bisou", not understanding or relating to the song or performance, is a sign of a much wider divide his character faces in understanding the appeal of the fast-changing times, where music was ever more integral to culture and as a result, advertising. Don asks, "When did music become so important?"

Megan: "It's always been important."

Don: "I mean jingles, yeah, but now everybody keeps coming in, looking for some song. And they're so specific."

Megan: You love specific."

Don: But I have no idea what's going on out there.

Megan: "Well, no one can keep up. It's always changing." 

The episode concludes with Megan handing Don The Beatles' Revolver, and suggesting he start by listening to the psychedelic, LSD & Indian-inspired tape-loop-distorted "Tomorrow Never Knows" (a track hinting at the band's new psych direction), which he abruptly lifts the needle on having got only a minute and a half or so into the Lennon-helmed track.

The show reportedly paid $250,000 for the rights to the track.

The fifth series closes with one of the most iconic Bond theme songs, Nancy Sinatra's "You Only Live Twice" - which overlays Rogers LSD trips, Megan's acting re-birth/success from copy writing, Peggy's new power and loneliness and Don's fateful unanswered response to the question at the bar "Are You Alone?"; all characters searching for a dream.  And, much like the Bond films, Mad Men is known for its iconic end-credits songs.

You Only Live Twice or so it seems / One life for yourself and one for your dreams / You drift through the years and life seems tame / Till one dream appears and love is its name / And love is a stranger who'll beckon you on / Don't think of the danger or the stranger is gone / This dream is for you, so pay the price / Make one dream come true, you only live twice 

Even in its first episode Mad Men plays with the sincerity of its music – Vic Damone's "On The Street Where You Live", a heartfelt ballad also used in My Fair Lady, is heard as we see Don's white-picket fence Ossining life, just as the viewer is shown that it's nothing more than an illusion. This method is also employed to comic effect with jovial pieces cut against surreal, Lynchian-style sinister scenes like Betty's shooting at birds on her lawn while Bobby Helms's "My Special Angel" plays. Series 1 culminated with Dylan's "Don't Think Twice, It's Alright", with Don "sit[ting] and wonder[ing] why" as he is alone on the stairs of his house over Thanksgiving, where he imagines a better life where he was the family man he's failing at pretending to be.

Dylan's whimsical dismissal of a partner and apparent pep-talk mirrors Draper's conflicted desires and despairs in relation to his marriage - he can't commit to it but desperately wants the happiness and sense of self he thinks it should bring.

Whether they're being used as ironic coda, historical sign-posts, or nods to the audience, the much varied canon of Mad Men's soundtrack can only add to the immersion and enjoyment of one of the most substantial dramas of the last decade.

So, as the final part of the seventh season begins to air, I'm more than keen to know whether we'll hear RJD2's beats, a yet-unknown late 60s hit, or just silence when the last ever episode's end credits roll. While we wait, let's all enjoy this alternative take on Don's first vinyl listening party, this one-of-a-kind Mad Men/The OC mash up and a special Best Fit-curated top 20 songs from the series Spotify playlist.

Mad Men runs from 5 April on AMC in the US and 16 April on Sky Atlantic in the UK.