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D'Addario · Phosphor Bronze · 13-17-26-35-45-56

D'Addario EJ17 (13-17-26-35-45-56) in C standard on a 25" scale

13-56 Medium, Phosphor Bronze Acoustic Guitar Strings on an acoustic guitar with a 25" scale, tuned to C standard (C4 G3 Eb3 Bb2 F2 C2), pulls 112.3 lb51.0 kg500 N in total and 18.7 lb8.49 kg83 N per string on average. That is a loose feel for an acoustic guitar. The set is very even (spread 2.5%). String 4 (Bb2) deviates most: +16% from the set average.

Total tension
112.3 lb51.0 kg500 N
Average per string
18.7 lb8.49 kg83 N
Feel
loose
medium ≈ 26.8 lb12.14 kg119 N per string
Set your own preferred feel
Balance
very even
spread 2.5%

Tension per string

01020lb0510kg050100Nset averagemedium (12-53)1C4.01316.6 lb7.54 kg74 N2G3.01716.0 lb7.24 kg71 N3Eb3.02621.3 lb9.65 kg95 N4Bb2.03521.8 lb9.87 kg97 N5F2.04519.9 lb9.02 kg88 N6C2.05616.8 lb7.64 kg75 N
The bronze dashed line is the medium-feel target: the average per-string tension of a 12-53 set on a 25.5" scale in E standard (26.8 lb12.14 kg119 N). Loose and tight are measured against it.Line thickness follows the string gauge; textured lines are wound strings. Hover, tap or tab to a string for details.
#NoteHzGaugeItemType Tensionvs avg
1C4261.6 .013PL013plain 16.6 lb7.54 kg74 N−11%
2G3196.0 .017PL017plain 16.0 lb7.24 kg71 N−15%
3Eb3155.6 .026PB026wound 21.3 lb9.65 kg95 N+14%
4Bb2116.5 .035PB035wound 21.8 lb9.87 kg97 N+16%
5F287.3 .045PB045wound 19.9 lb9.02 kg88 N+6%
6C265.4 .056PB056wound 16.8 lb7.64 kg75 N−10%
Total112.3 lb51.0 kg500 N

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Similar sets in C standard, 25"

SetGaugesAvg per stringTotalFeelBalance
Elixir 16182 13-17-25-32-42-5317.6 lb7.96 kg78 N 105.3 lb47.8 kg469 Nlooseeven
Elixir 11100 13-17-26-35-45-5618.5 lb8.40 kg82 N 111.1 lb50.4 kg494 Nloosevery even
Elixir 11102 13-17-26-35-45-5618.5 lb8.40 kg82 N 111.1 lb50.4 kg494 Nloosevery even
EJ17 (this page) 13-17-26-35-45-5618.7 lb8.49 kg83 N 112.3 lb51.0 kg500 Nloosevery even
Elixir 16102 13-17-26-35-45-5619.0 lb8.63 kg85 N 114.1 lb51.8 kg508 Nloosevery even
Elixir 11125 16-18-28-35-45-5620.9 lb9.47 kg93 N 125.3 lb56.8 kg557 Nlooseuneven

Best match for a medium feel in C standard, 25"

Ranked by how close every string is to 26.8 lb12.14 kg119 N (lower deviation is better).

  1. Elixir 11125 16-18-28-35-45-56 deviation 25.2%, average 20.9 lb9.47 kg93 N, uneven
  2. Elixir 16102 13-17-26-35-45-56 deviation 29.2%, average 19.0 lb8.63 kg85 N, very even; same gauges: 11100, 11102
  3. D'Addario EJ17 13-17-26-35-45-56 deviation 30.2%, average 18.7 lb8.49 kg83 N, very even

More for the EJ17

Other tunings on 25": E standard, Drop D, Eb standard, D standard, Drop C, Open G, Open D, DADGAD

C standard on other scales: 24.75", 25.5"

About these numbers

Tension is calculated, not measured: T = μ · (2 · L · f)², where μ is the string's mass per unit length (unit weight), L the vibrating length (scale) and f the pitch (A4 = 440 Hz, equal temperament). kg means kilogram-force: 1 kg ≈ 9.81 N ≈ 2.205 lb.

How a set feels also depends on the guitar's setup: action height, break angle over the nut and saddle, string length behind the nut and bridge, and your playing style. Plain strings feel stiffer than wound strings at the same tension. Use these figures to compare sets, not as an absolute measure of feel.

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