Sides one and four ("Great Expectations/Orange Lady" and "Lonely Fire") were recorded three months after the Bitches Brew sessions and incorporate sitar, tampura, tabla, and other Indian instruments.

They also mark the first time since the beginning of Miles Davis's electric period that he played his trumpet with the Harmon mute which had been one of his hallmarks, making it sound much like the sitar.

It has a drum and electric bass groove (which in fact at one point breaks down due to mistiming) and a plethora of musicians improvising individually and in combinations over variations on the bassline.

[7] The recording is a riff and groove-based, with a relatively sparser line-up of Steve Grossman on soprano saxophone, Dave Holland on bass, Jack DeJohnette on drums, and John McLaughlin on guitar with wah-wah pedal.

[6] In his book Running the Voodoo Down: The Electric Music of Miles Davis, Davis-biographer Phil Freeman describes this technique as "100 percent Macero" and writes of its significance to the track as a whole, stating: This doesn't create the effect of two drummers.

[7] The recording begins with McLaughlin's funky wah-wah lines, backing Grossman's sharp, restrained playing, with Davis's first trumpet solo entering at four minutes with scattered ideas.

[6] Music journalist Todd S. Jenkins writes of this passage in the recording, "Thanks to the then-new wonders of noise gate technology, Jack DeJohnette’s drums and cymbals flit back and forth rapidly from left to right in the mix.

[12] Phil Freeman wrote of this "doubling effect", stating "Miles's two solos fit together perfectly, creating a feel similar to that of New Orleans jazz, with two trumpets weaving intricate, complementary lines around each other".

[17] According to Todd S. Jenkins of All About Jazz, "The long, ever-droning, darkly exotic electric music, and in fact the very idea of just four songs taking up four full sides of an album, was not too appealing to critics or the general market at a time when short, sharp disco tunes were beginning to chart like wildfire.

He singled out "Lonely Fire" as a highlight, writing that "after meandering at the beginning [it] develops into lyrical mood music reminiscent in spirit and fundamental intent of Sketches of Spain".

[23] Alternative Press called the album "essential....colorful and exotic" and wrote that it represents "the high water mark of his experiments in the fusion of rock, funk, electronica and jazz".

[26] Stylus Magazine's Edwin C. Faust commented that "a world without this music would be a considerably emptier place" and cited it as Davis's "greatest achievement" with regard to an album's "overall effect".

[9] Faust felt that critics who originally found it "scattered" and "unfocused" might not have if they had had "the knowledge of recording dates and band line-ups", while elaborating on its significance to Davis's catalogue: "Big Fun has a very consistent vibe throughout.

"[9]DownBeat critic John Ephland commented that "there is indeed a sense of adventure, of taking chances with so much talent, and with such skeletal designs", adding that "Big Fun reinforces the notion that Miles' primary contributions to music have come via orchestrating, organizing, enabling.