[1] Upon release, Replica received positive reviews from music critics and subsequently featured in the year-end lists of the best albums of 2011 by several publications, including The Boston Globe, Pitchfork, and Resident Advisor.

In contrast to his previous synthesizer-based releases as Oneohtrix Point Never, Replica was produced around audio samples from television advertisements procured by Lopatin, with the ads mainly dating back to the 1980s and 1990s.

"[4] Asked why he opted to use commercials as sample sources, Lopatin described his process as "looking for old things that are meaningful" then "restructuring and rearranging it to interfere with the original narrative and creating this new poetry.

"[2] Replica is more substantially sample-based than Lopatin's previous work, and it has been characterized by Miles Bowe of Stereogum as "chopped and screwed plunderphonics"[10] and by Larry Fitzmaurice of The Fader as "skyward sampledelia.

's Mark E. Rich describes it as "a sharp left turn that has him indebted to early 2000s electronic visionaries like Matmos, Akufen and Matthew Herbert, utilizing a specific sample source across the record.

"[15] Jeff Siegel of Resident Advisor notes that "where many of his peers and forebears build their ambience from microscopic variations on the same few sounds, Lopatin doesn't settle for long", citing "Andro", where opening synthesizer swells eventually give way to a "drain-swirl of errant ticks and drums", and the "cut-up vocals" of "Remember".

[14][19] One of the album's more "percussive moments", "Child Soldier" incorporates "voices programmed into a martial cadence" juxtaposed with distorted samples and synthesizer sounds, and Carlson describes the song as "the thesis of the record; smooth meets agro.

[32] Mark Richardson of Pitchfork found "a real sense of discovery here, or possibilities being probed" and wrote that "what's most striking about Replica is how well-constructed these tracks are, which is especially impressive given the record's brevity".

Club's Christian Williams wrote that "its great strength and most beguiling feature is its ability to sand spiky textures down into soothing ones, and to transform the anodyne into the anxiety-inducing, simply through repetition.

[38] K. Ross Hoffman of AllMusic stated that though the album's reliance on samples of commercials "makes for an intriguing compositional back-story—and it clearly provided him a rich sound palette from which to draw—it's rare that that source material is specifically evident while listening; at best it functions on a more energetic, subconscious level.

[36] Dave Simpson of The Guardian stated that "if Replica occasionally drifts – literally – too close to the whiffy bongs and flotation tanks of 90s chillout, it's never predictable, and is best experienced in a continuous sitting".