How Long Are Songs

| Gabriel |

Last night Scott Golder asked me how long pop songs are. I checked the Whitburn file’s “pop annual” tab to see this, at least for hit singles. The “time” variable appears consistently starting in the mid-50s. Just to be safe though I only looked at data starting with 1960 through 2008 (which is when my copy of the Whitburn file ends).

The short answer is that there’s a bimodal distribution, with one mode a bit shy of three minutes and another mode of a bit shy of four minutes. There are very few hit songs under two minutes. (Sorry Black Flag, sucks to be you). There are also relatively few hit songs over five minutes, though the right tail extends pretty far, with the following songs being over eight minutes: “Everybody Move” by Cathy Dennis, “The Astronauts (Parts 1 and 2)” by Jose Jimenez, “I Will Possess Your Heart” by Death Cab for Cutie, “American Pie (Parts 1 and 2)” by Don McLean, “November Rain” by Guns N Roses, and “A Better Place to Be (Live) (Parts 1 & 2)” by Harry Chapin. (Honorable mention to “2 Legit 2 Quit” by MC Hammer at 7:55).

Bimodal distributions always make me nervous, so let’s break this up by decade.

Breaking it up by decade makes it clear that the “bit under three minutes” mode is disproportionately songs from the 1960s and the “bit under four minutes” mode from subsequent periods. This makes sense when you realize that the dominant technological format of the 1960s was the 7-inch 45rpm single, which had a limit of three minutes. In contrast, 45s were less commercially important in subsequent periods and such technological formats as 12 inch 33rpm LPs, cassettes, CDs, and MP3s have no such time limitation that would reasonably matter for a single song. Moreover, there were also changes in radio. Genre-based radio formats were given a big boost in the late 1960s with the commercialization of the FM band and 1970s era formats like “Album-Oriented Rock” allowed for airplay that was more, well, album-oriented in terms of drawing cuts from LPs and not just 7 inches.

Another thing that’s pretty clear from looking at the decade-specific histograms is that there are sharp discontinuities. The three minute mark discontinuity in the 1960s is obviously a reflection of the technology of 7 inches. The other eras also show discontinuities at 3 and half minutes in the 1970s and 4 minutes in the 1980s and 1990s, with much weaker discontinuities at 4 minutes in the 1970s and 2000s. The recent 3:30 and 4:00 discontinuities are much harder to explain than the old 3:00 discontinuity because they don’t reflect a hard technological constraint. Rather, they seem to reflect a convention of radio airplay. Here’s a passage from Jacob Slichter’s one-hit wonder memoir, So You Want to Be a Rock N Roll Star (p 138-9):

In anticipation of “crossing over” the single to radio formats other than alternative rock, we did a pop mix (by Don Gehman with lighter portions of electric guitar) and an acoustic mix (by Puig, a soccer-mom version with no electric guitars and no drums until the second verse). Each mix had to be edited down to under four minutes, an important limit in the mind of radio programmers. (To submit a single with a track length of 4:01 is as foolish as pricing kitchen knives sold on television at $20.01). We pestered Bob Ludwig, the mastering engineer, with a slew of editing adjustments. “Okay, shorten the intro to what it was two verses ago, cut eight bars off the end of the bridge, and undo the cuts we asked you to make to the final chorus.”

(btw, the album version of “Closing Time” clocks in at 4:34.)

Nonetheless, the strength of this convention seems to have weakened since Slichter’s story takes place in 1998, with the 2000s showing a much weaker discontinuity and many more songs a few seconds over 4 minutes than did the 1990s. I don’t know why this is, but I think it’s worth noting that it doesn’t necessarily reflect weakening of the 4 minute radio rubicon but could also reflect changes to how the chart is calculated, such as the rise of a digital singles market (which has been weighted into the Billboard Hot 100 since 2005), or how the time variable is measured (perhaps it’s the iTunes or album time, not the time for the radio edit).

Here’s the code:

cd ~/Documents/codeandculture/whitburn
clear all
insheet using popannual.txt, clear
gen min=real(regexs(1)) if regexm(time,"([0-9]+)\:")
gen sec=real(regexs(1)) if regexm(time,"\:([0-9]+)")
gen time_sec=min*60+sec
sum min sec time_sec

gen decade=.
replace decade=1 if year>=1960 & year<1970
replace decade=2 if year>=1970 & year<1980
replace decade=3 if year>=1980 & year<1990
replace decade=4 if year>=1990 & year<2000
replace decade=5 if year>=2000 & year<2010
lab def decade 1 "1960s" 2 "1970s" 3 "1980s" 4 "1990s" 5 "2000"
lab val decade decade
histogram time_sec if decade!=., discrete xlabel(0(60)600) title("Billboard Hits, 1960-2008")
graph export time.png, replace width(1600)
histogram time_sec if decade==1, discrete xlabel(0(60)600) title("Billboard Hits, 1960-1969")
graph export time_1960s.png, replace width(1600)
histogram time_sec if decade==2, discrete xlabel(0(60)600) title("Billboard Hits, 1970-1979")
graph export time_1970s.png, replace width(1600)
histogram time_sec if decade==3, discrete xlabel(0(60)600) title("Billboard Hits, 1980-1989")
graph export time_1980s.png, replace width(1600)
histogram time_sec if decade==4, discrete xlabel(0(60)600) title("Billboard Hits, 1990-1999")
graph export time_1990s.png, replace width(1600)
histogram time_sec if decade==5, discrete xlabel(0(60)600) title("Billboard Hits, 2000-2008")
graph export time_2000s.png, replace width(1600)

*have a nice day