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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" scale

13-56 Medium, Phosphor Bronze Acoustic Guitar Strings on an acoustic guitar with a 25" scale, tuned to Drop C (D4 A3 F3 C3 G2 C2), pulls 137.2 lb62.2 kg610 N in total and 22.9 lb10.37 kg102 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
137.2 lb62.2 kg610 N
Average per string
22.9 lb10.37 kg102 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)1D4.01321.0 lb9.50 kg93 N2A3.01720.1 lb9.13 kg89 N3F3.02626.8 lb12.16 kg119 N4C3.03527.4 lb12.43 kg122 N5G2.04525.0 lb11.36 kg111 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
1D4293.7 .013PL013plain 21.0 lb9.50 kg93 N−8%
2A3220.0 .017PL017plain 20.1 lb9.13 kg89 N−12%
3F3174.6 .026PB026wound 26.8 lb12.16 kg119 N+17%
4C3130.8 .035PB035wound 27.4 lb12.43 kg122 N+20%
5G298.0 .045PB045wound 25.0 lb11.36 kg111 N+10%
6C265.4 .056PB056wound 16.8 lb7.64 kg75 N−26%
Total137.2 lb62.2 kg610 N

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Similar sets in Drop C, 25"

SetGaugesAvg per stringTotalFeelBalance
Elixir 16182 13-17-25-32-42-5321.4 lb9.72 kg95 N 128.6 lb58.3 kg572 Nloosemoderately uneven
Elixir 16077 12-16-24-35-45-5621.7 lb9.84 kg96 N 130.1 lb59.0 kg579 Nloosemoderately uneven
Elixir 11100 13-17-26-35-45-5622.6 lb10.25 kg101 N 135.6 lb61.5 kg603 Nloosemoderately uneven
Elixir 11102 13-17-26-35-45-5622.6 lb10.25 kg101 N 135.6 lb61.5 kg603 Nloosemoderately uneven
EJ17 (this page) 13-17-26-35-45-5622.9 lb10.37 kg102 N 137.2 lb62.2 kg610 Nloosemoderately uneven
Elixir 16102 13-17-26-35-45-5623.2 lb10.53 kg103 N 139.2 lb63.2 kg619 Nloosemoderately uneven

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

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 15.6%, average 23.2 lb10.53 kg103 N, moderately uneven; same gauges: 11100, 11102
  2. D'Addario EJ17 13-17-26-35-45-56 deviation 16.9%, average 22.9 lb10.37 kg102 N, moderately uneven
  3. Elixir 11125 16-18-28-35-45-56 deviation 20.5%, average 25.6 lb11.60 kg114 N, uneven

More for the EJ17

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

Drop C 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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