After ending their contract with Virgin Records in 2005, the band felt their previous album Fly or Die (2004) was too consistent.

While touring in promotion of their previous album, Fly or Die, N.E.R.D ended their contract with Virgin Records in 2005.

Williams and fellow band member Chad Hugo later established Star Trak Entertainment, a subsidiary of Interscope Records.

Williams explained that the title was based on synesthesia, a neurological phenomenon the band learned of while watching the Discovery Channel.

[10] The typical process of recording was described as "Williams arrives at the studio, ideas in full flower, and lays down both a beat (either programmed or played on an assortment of buckets) and vocals."

"[12] Don Was, a musician and record producer, thought that the band was on a creatively fulfilling path, calling their musical style "really innovative".

[9] Williams felt music lacked energy, citing Limp Bizkit's "Nookie" as the last energetic record.

Williams suggested his engineer, Andrew Coleman, to "put the drums and bass on the right, keys in the middle, and the mothafucking guitar and backgrounds on the left".

"[10] The Hives' members - Chris Dangerous (drums/percussion), Nicholaus Arson (guitar), Vigilante Carlstroem (guitar), Dr. Matt Destruction (bass) - contributed instrumentals on "Time For Some Action" and "Windows", with The Hives' frontman Howlin' Pelle Almqvist providing guest vocals on "Time For Some Action".

[13][14] In promotion of the album, N.E.R.D performed in Kanye West's Glow in the Dark Tour as well as the Isle of Wight Festival.

[11][7] The band also performed at the Austin City Limits festival, where they encouraged fans to dance on stage and urged them to vote in the 2008 United States elections.

[19] It peaked in the top 20 in Australia, Canada, the Netherlands, Switzerland and the United Kingdom, while also charting in the several other regions, including Austria, Belgium, France and Italy.

[31] Some writers noted and praised the heavy use of electronic, bass and funk beats,[25][32][33] while others suggest The Neptunes were unable to blend R&B and rock.

[26] Anthony Henriques of PopMatters lauded the production, saying that "their signature drums and spaced-out samples sound as good as ever here", going on to say "[t]he overall balance between live and electronic instrumentation is also the best they have managed on any of the N.E.R.D.

[27] Adrian Ruhi of Okayplayer gave the album a score of 88 out of 100 and called some of the songs "a dynamic mess", but noted it was "a good thing".

[8] Henriques of PopMatters noted that Williams is not a "technically gifted rapper", he "does not have a beautiful voice" and his lyrics are "typically inconsequential in a 'saying shit just to sound cool' sort of way", but found strengths in his choruses, which he pointed out "typically use a catchy phrase or recognizable melody as an anchor for his nonsensical verses".

[28] Dan Charnas of The Washington Post commended N.E.R.D for their songwriting, writing that Seeing Sounds "combines the adolescent and clever".

[34] The Times writer Priya Elan gave the album 4 out of 5 stars and wrote that band is "pushing the boundaries of the popular song".

[30] In his Consumer Guide, Robert Christgau gave the album a three-star honorable mention () and stated, "Beats of course, songs usually, singing barely--especially sincere-type singing"; he also picked out two songs from the album: "Anti-Matter" and "Everyone Nose (All the Girls Standing in the Line for the Bathroom)".