Building on the arrangements in their demo songs recorded in 2004, the band members moulded tracks largely through live takes during the Silent Alarm studio sessions.

The compositional focus was on rhythm and the drum and bass parts, while lyricist Kele Okereke's writing examined the feelings and hopes of young adults, including views on global politics.

[3] After drummer Matt Tong auditioned and joined the trio, the band members' songwriting evolved and they started crafting tracks for Silent Alarm.

[4] Self-recorded in a small, hired space in Acton, London, the song was followed by the May 2004 double A-side single, "Banquet/Staying Fat", produced by Paul Epworth.

[5] Following exposure with British magazines and newspapers and a successful performance on BBC Radio 1,[6] Bloc Party received a contract offer from Parlophone.

Okereke has suggested that forward-thinking bands reach a plateau and start to question the boundaries of their medium; this leads to experimentation with elements from other genres.

[13] Preferring live recording takes for better sound authenticity,[11] Epworth's style separated the band's elements by accentuating the bass and by allowing the guitarists space to improvise.

[15] The producer meticulously tuned and retuned the components of the drum kit for a specific sound and used ribbon or condenser microphones lined up in an equidistant formation.

[11] According to Lissack, the basic idea was to emulate the "optimum audio representation" of songs heard in a club environment by adding guitar lines on top of boosted drum and bass tracks.

As the sessions progressed, the band members started experimenting with distortion pedals to add to their "chiming, clean guitar sound",[11] although they did not listen to the producer about song structure.

[12] He called the final version of Silent Alarm "technicolour" due to its stylistic choices and indicated that Bloc Party achieved the aim of making the songs sound "better and bigger" when they were recorded in the studio.

[4][19] Moakes later pointed out that the band members were relative novices when they entered the recording sessions, and that for the most part they only did what they were advised; this is an additional reason why the album is disjunct and not focused on any particular musical style.

[21] "Helicopter" has a quick tempo of 171 beats per minute, while "Positive Tension" begins with a solitary bassline and builds up pace, first with a rhythmic drumming pattern, and then with a guitar solo towards its conclusion.

[20] During the studio sessions, the Bloc Party EP version of "She's Hearing Voices" was reworked to include reverberation and stereo separation of the instrumental parts.

"Pioneers" opens with a series of delayed guitar harmonics,[20] while "Price of Gas" is driven by a marching-like sound created by Moakes walking in the studio with planks of wood strapped to his feet.

[24] "Positive Tension" concerns boredom and its dangers, focusing on how it "can lead you into dark places",[25] while "Banquet" details "how sex is about power, submission, domination and real rapacious desire".

[3] The lyricist has described the moment in "This Modern Love" when the backing vocals enter the mix before the second chorus as "perfect", because it evokes the idea of "two people on the telephone, who can't touch each other, and as the song and the conversation progress, everything amplifies".

[17] Bloc Party EP was distributed in America in September 2004 by Dim Mak Records, while the band performed several gigs at the end of the year in the US and Canada.

[8] The release of Silent Alarm was preceded by the marketing of Little Thoughts EP in Japan in December 2004, containing previous UK singles "Little Thoughts/Tulips" and "Helicopter" and new material.

[31] Chosen because the album has a sense of disquiet, the name comes from an article in New Scientist about an early detection system for earthquakes in Japan,[14] while the cover art is based on a bare winter landscape by freelance photographer Ness Sherry.

[33] The US marketing was geared to establish a long-term fan base among "tastemakers and early-adopter rock enthusiasts", rather than a short-term emphasis on radio play.

[45] Drowned in Sound's Gen Williams described the album as "mature and expansive" and wrote that "the autonomy, creativity and sheer, elastic beauty that spans this debut more than justifies the rapidly accelerating hype".

[53] Summing the record up as "dance rock, but highly caffeinated", Barry Walters of Rolling Stone explained that the tracks are emotive and rhythmic in equal measure,[1] while Nick Southall of Stylus Magazine thought that every song is "full of thrilling ideas and inspired moments".

[54] Johnny Davis of Q labelled Silent Alarm "an arty, confident and exhilarating debut",[51] while Joshua Glazer of URB compared Bloc Party to "every legendary band ever who followed an EP with an even better album and on into greatness".

[2] Romano and Glazer compared Silent Alarm to U2's early work,[53][52] while Walters claimed that it distills "twenty-five years of spiky British rock, from The Cure to Blur to hot Scots Franz Ferdinand".

[1] Pitchfork's Nitsuh Abebe noted particular similarities between "Banquet" and Franz Ferdinand's second single "Take Me Out", calling both songs "wonderfully tight and energetic—the same kind of spiffy half-dancing rock".

Dan McIntosh of PopMatters stated that the concert documentary shows the band "can consistently pull off its material live", but concluded that it focuses on Bloc Party "much too intently, far too soon".

The tour would take place in October and November and would travel to Amsterdam, Paris, Berlin, Brussels, Dublin plus dates in the UK, Australia and New Zealand.

"Silent Alarm didn't just make the band household names—it was a pivotal post-millennium release, effectively securing the reputation of its producer Paul Epworth and serving as a blueprint for domestic indie acts to follow: you can wear your heart on your sleeve while delivering punchy, pop-savvy rock music that appealed to radio heads and dancefloor doyens alike, and that bridged the commercial-critical divide brilliantly.