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

D'Addario EJ17 (13-17-26-35-45-56) in Drop C on a 25.5" scale

13-56 Medium, Phosphor Bronze Acoustic Guitar Strings on an acoustic guitar with a 25.5" scale, tuned to Drop C (D4 A3 F3 C3 G2 C2), pulls 142.7 lb64.7 kg635 N in total and 23.8 lb10.79 kg106 N per string on average. That is a loose feel for an acoustic guitar. The set is moderately uneven (spread 9.4%). String 6 (C2) deviates most: −26% from the set average.

Total tension
142.7 lb64.7 kg635 N
Average per string
23.8 lb10.79 kg106 N
Feel
loose
medium ≈ 26.8 lb12.14 kg119 N per string
Set your own preferred feel
Balance
moderately uneven
spread 9.4%

Tension per string

0102030lb0510kg050100Nset averagemedium (12-53)1D4.01321.8 lb9.89 kg97 N2A3.01720.9 lb9.49 kg93 N3F3.02627.9 lb12.65 kg124 N4C3.03528.5 lb12.94 kg127 N5G2.04526.1 lb11.82 kg116 N6C2.05617.5 lb7.95 kg78 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
1D4293.7 .013PL013plain 21.8 lb9.89 kg97 N−8%
2A3220.0 .017PL017plain 20.9 lb9.49 kg93 N−12%
3F3174.6 .026PB026wound 27.9 lb12.65 kg124 N+17%
4C3130.8 .035PB035wound 28.5 lb12.94 kg127 N+20%
5G298.0 .045PB045wound 26.1 lb11.82 kg116 N+10%
6C265.4 .056PB056wound 17.5 lb7.95 kg78 N−26%
Total142.7 lb64.7 kg635 N

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Similar sets in Drop C, 25.5"

SetGaugesAvg per stringTotalFeelBalance
Elixir 16182 13-17-25-32-42-5322.3 lb10.12 kg99 N 133.8 lb60.7 kg595 Nloosemoderately uneven
Elixir 16077 12-16-24-35-45-5622.6 lb10.24 kg100 N 135.4 lb61.4 kg602 Nloosemoderately uneven
Elixir 11100 13-17-26-35-45-5623.5 lb10.66 kg105 N 141.1 lb64.0 kg627 Nloosemoderately uneven
Elixir 11102 13-17-26-35-45-5623.5 lb10.66 kg105 N 141.1 lb64.0 kg627 Nloosemoderately uneven
EJ17 (this page) 13-17-26-35-45-5623.8 lb10.79 kg106 N 142.7 lb64.7 kg635 Nloosemoderately uneven
Elixir 16102 13-17-26-35-45-5624.1 lb10.95 kg107 N 144.9 lb65.7 kg644 Nloosemoderately uneven

Best match for a medium feel in Drop C, 25.5"

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

  1. Elixir 16102 13-17-26-35-45-56 deviation 12.9%, average 24.1 lb10.95 kg107 N, moderately uneven; same gauges: 11100, 11102
  2. D'Addario EJ17 13-17-26-35-45-56 deviation 14.2%, average 23.8 lb10.79 kg106 N, moderately uneven
  3. Elixir 16077 12-16-24-35-45-56 deviation 18.6%, average 22.6 lb10.24 kg100 N, moderately uneven; same gauges: 11075, 11077

More for the EJ17

Other tunings on 25.5": E standard, Drop D, Eb standard, D standard, C standard, Open G, Open D, DADGAD

Drop C on other scales: 24.75", 25"

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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