Case Study: "Pentagon" - Sean Murray

Case Study: "Pentagon" - Sean Murray


In this case study I'll be performing an analysis of Sean Murray's "Pentagon", which is featured in the game, Call Of Duty: Black Ops. I intend on using this song as a reference track for an upcoming project, involving myself and Chris Ware creating the composition and sound design for the game Transmutation (Jordon Dodds, Nic lyness, Pritish Choudhary).


Pentagon is a fusion between classical, rock and electronic styles. Call Of Duty: Black Ops is a game set during the Cold War. For this Murray strived to emulate the styles of the era through Hungarian composers such as Kurtag and Ligeti; and American composers Lazarof and Druckman. To give the music a contemporary adaption Murray added synthesizers, sampled percussion and distorted, heavy metal style guitars. Together these elements create a gripping, tense classical arrangement, true to the era of the game, in a contemporary style for today's listener.


Sean Murray

Sean Murray

Sean Murray, from California, is a score composer for film, TV and video games. He has composed for titles such as, Call Of Duty: Black Ops and World At War; Buffy The Vampire Slayer; and God, The Devil and Bob




  • Key signature: D Major
  • Time signature: 4/4 (with some variations)
  • Tempo: 170 Bpm
  • Length: 3 min 14 secs
  • Bar count: 140 Bars

Structure / Instrumentation

Pentagon has an evolving structure style. This is performed by instruments appearing and disappearing throughout the song, while introducing diverse rhythms at the same time. There are also several time signature changes, which confuses the listener as to the tempo of the song, giving the music a more 'natural world' feel. This style of structure works well in composing for games as it doesn't often take the player's attention away from gameplay unless to add tension. 


Due to the loose structure of the song, I have divided the song into 8 sections labeled A through H rather than the naming systems common in pop music (i.e. intro, verse, chorus, etc).

Section A (00:00) 22 Bars - Song commences with high velocity intermittent percussion while brass section slowly fades in. A bowed double bass holds a long ominous note. Two synths play overhead. There are several time signature changes through this section: 4/4 (4 bars), 2/4 (1 bar), 3/4 (1 bar), 4/4 (1 bar), 3/4 (1 bar), 4/4 (5 bars), 5/4 (1 bar), 4/4 (5 bars), 3/4 (2 bars), 4/4 (1 bar). In the final 3 bars of tis section the strings and brass rise in velocity as if to introduce the body of the song.

Section B (00:29) 15 Bars - The brass is the primary rhythm keeper in this section, playing short punchy notes. The percussion is quite random as it constantly switches between instruments. Heavily distorted guitar is introduced in bar 27. All instruments drop off at bar 33 to be replaced with the two synths from Section A, which rise in velocity to transition to Section C. There is also a 1 bar time signature change to 5/4 before Section C.

Section C (00:51) 11 Bars - The snare and strings are the main rhythm keepers in this section while the guitar play the main 'hook' rhythm, which is then replaced by the brass. A second guitar occurs briefly at bar 41 and is panned back and forth as it fades out. At bar 45 Guitar 1 is replaced with a more mellow guitar til the end of the section. Also at bar 45 a bouncy synth is added. There is a time signature change to 3/4 from bar 45 to 48. All instruments drop off in the transition to Section D.

Section D (01:05) 22 Bars - A mellow bowed double bass creates a noise floor in this section for the other instruments to cover. The string section enters at bar 53 with the main rhythm. The brass enter at bar 61 with a long and mellow crescendo. Two synths play through out the whole section while three other synth sound at various points.

Section E (01:36) 21 Bars - This section is very similar to Section D as the string melody and Synth 1 are carried on from the previous section. The brass intermittently play long crescendo notes. Also another synth is added intermittently playing a 3 note rhythm.

Section F (02:06) 16 Bars - This section begins with a cymbal crash along with a synth, which slightly resembles a scream. Two more synths are introduced and play throughout this section. The percussion is the rhythm keeper for this section while the strings play long, flowing notes.

Section G (02:29) 16 Bars - The section starts again with the double bass as the noise floor along with a high pitched synth and bouncy synth, which all play throughout the section. The rest of the string section appears at bar 112, playing and elongated rhythm. The only percussion is two mellow bass drum hits at bars 116 and 120.

Section H (02:51) 15 Bars - The strings adopt the same rhythm as in Section E, while the brass play long elongated notes. A bouncy synth appears in bar 128. The only percussion is a cymbal roll followed by a bass drum hit to signal the end of the song along with the assistance of a female choir style vocal (no lyrics).

Instrumental Characteristics

Although an orchestra was recorded for this song, the percussion appears to only be processed samples. This is suggested by the fact that the velocity in all percussion is very consistent. Also it is sounds much more separated from the other instruments than what would be expected from an orchestral recording, as there would be bleed from the other instruments. It's possible that percussion was recorded with the orchestra and removed from the final mix.

The orchestra would have been recorded together. There is separation between the different instrument groups (brass, strings, woodwind), which could have been achieved by having an overhead stereo mic setup (possibly X-Y) above each instrumental group. The nice, warm tone over all instruments suggests the use of small diaphragm condenser mics rather than large diaphragm.

There are three different guitar tracks, although all are quite short. They are all heavily distorted and all have similar distortion. The aspects in which they vary are playing style and pickup position. The first guitar at 00:35 is palm muted as it is punchy with a very short release tail. The pickup would be away from the bridge, which gives it that warmer low mid tone. The second guitar at 00:51 is strummed with no muting with and uses a pickup closer to the bridge giving it a brighter tone. These two guitars still share very similar tones, which suggests the same guitar was used for each. The third guitar at 00:55 and 01:01 is also palm muted. It has slightly lower mid (dull) tones, which may suggest that a different guitar was used or the mic position on the speaker cone was different to the first two. Perhaps the mic was closer to the centre of the cone for the first two guitars and then moved towards the edge for the third.

There are seventeen synth patches in total throughout the song. Many of which only appear for a few seconds while some will play for entire section. None of the synths actually repeat in several sections. There are quite high frequency 'airy' style patches, which appear in Sections A and G; many bouncy patches, which feature in Sections D, E, F and G. All patches have a very clean and crisp tone, which suggests that they are all analog rather than digital. This helps the electronic style music blend with the acoustic elements.

The female vocal that sounds just prior to the conclusion of the song is likely to be recording with a large diaphragm condenser mic, which is suggested by the lack of low frequencies. However, this is difficult to discern due the large amount of reverb on the vocal.

Overall Spectral / Dynamic Content

This is a very dynamic song both dynamically and spectrally. There is not a lot of emphasis on the higher frequencies while the main emphasis lies within the 50-200Hz range. The high frequencies appear to roll off heavily from 2kHz onwards. This may be to leave room for foley and dialogue during gameplay. Reverb is used generously on the entire track, most likely to glue the instruments together. Some of the brass sometimes appears distorted, however it is possible that the sound is actually distorting within the instrument. The amplitude is also quite dynamic throughout the track, with some sections at 0dBFS and others sitting around -15dBFS.

There is a lot of movement in the stereo field but doesn't appear to be due to automation. Instruments are placed as they would for an orchestra performance. The only automation being on the guitar being panned side to side and the a couple of the synths being bounced back and forth in the same fashion.


Sean Murray [Image] (2013). Retrieved August 9th, from

Video game Music. (2011, February). 17. Pentagon - Sean Murray [video file]. Retrieved August 9th, from

Greening, C. (2011). Interview with Sean Murray. Retrieved August 9th, from

Pro Tools 12 [Image] (2015). Avid. Retrieved June 20th.