Stringcharts

I have been trying to work out stringing regimes for traditional wire-strung Irish harps for over 20 years now. This work has been a combination of trial-and-error, and calculation and analysis. Since 2017 I have been working with the idea of memorised rules-based stringcharts.

It’s my opinion that the traditional way to string a harp is based on a simple rule-of-thumb, that there are pretty standard and stable rules that you can memorise to know what gauge of wire goes into which position. So whether you are stringing a new harp from scratch, or you need to replace a single broken string, you can look at the harp and say, well, that note in that position should be that gauge.

Setup and tuning of the harp

I think the harps used by the traditional Irish harpers from the 17th century right through to the early 20th century always went down at least as low as C or D two octaves below middle c′, and up to d‴ two octaves above middle c′ – I think this is the “minimum” that we expect a traditional Irish harp to have. Most Irish harps used in the inherited tradition have more strings than this at the top and at the bottom. There are two strings tuned to the same note, g below middle c′; these are called “na comhluighe” or “the sisters”. An octave lower than them is cronan G, and next below it there is a gap in the bass: one string can be tuned either up to bass F♮ or down to bass E, depending on the mode of the tune. This retunable string is called “tead leagaidh”. There may be other gaps lower in the bass as well.

You can download my free PDF instructions for tuning the harp.

19th century style Irish harps

From the early 19th century, a new improved design of wire-strung Irish harp became almost universal. These new harps, made by John Egan in Dublin, or copied from his work, are tall and have very long bass strings.

My recommended setup for the John Egan traditional wire-strung Irish harps follows the string counts taken down from the traditional harper Patrick Byrne in 1849:

Information from Patrick Byrne, 1849My understanding of what the notes would beMy suggested brass wire gauge
Longest wire,
5 wires of this
Lowest bass strings GG, AA, BB, C, and D1 mm
3 wires of the next sizeTéad Leagaidh E/F, Cronan G, and A0.8 mm
6 of the nextB up to lower comhluighe g0.7 mm
67 of the next say 7upper comhluighe g up an octave to f′0.6 mm
56 of the next say 5g′ up to d″ 0.48 mm
78 of the next say 8
34 in all
all the rest of the strings up to the top of the harp0.44 mm
Patrick Byrne (1790s – 1863)

The first column of this chart is the testimony of the harper and tradition-bearer, Patrick Byrne, as written down in 1849 by John Bell (Glasgow University Library MS Farmer 332, published by H.G. Farmer, ‘Some Notes on the Irish Harp’, Music & Letters vol XXIV, April 1943). Byrne’s testimony is not problem-free; most obviously he doesn’t tell us the actual gauges, and the mm diameters are my suggestions. His counts above the sisters have been emended by Bell, and even then they don’t add up to the 38 positions which Byrne’s harp apparently had. I don’t know if this vagueness about the exact count of each gauge above na comhluighe (the sisters) might be because John Bell was getting very confused and writing down wrong information, or because Patrick Byrne did not really think it mattered very much exactly where the treble transition points were between gauges.

My header photo shows me stringing a copy of one of the 1820s John Egan wire-strung Irish harps, from memory without using a written string-list.


18th century style Irish harps

Before the 1820s, the design of traditional Irish wire-strung harps was not standardised, and every example is different with different treble and bass range. However, they can all be strung with this very simple 4-gauge system.

I have used this system for quite a few 18th century style Irish harps now, from the petite Downhill and Otway models up to the huge Carolan and Mulagh Mast models. In my experience all of these types of harp work very nicely using this four gauge system; the same “rule of thumb” is used no matter what model the harp is. All you need to know is what is the highest note and how the bass strings below cronan G are organised (because this is different for each model).

Lowest bass strings up to cronan G1 mm
7 stringsA next above cronan, up to lower comhluighe g0.8 mm
7 stringsupper comhluighe g, up the octave to f′0.6 mm
all the resttreble g′ up to the top (Sometimes the high treble strings work best in iron instead of brass wire)0.48 mm
Arthur O’Neil (1730s-1816)

This chart for the 18th-century style harps is inspired by a comment made by the harper and tradition-bearer, Arthur O’Neil, who wrote in a letter around 1800, “My harp has thirty-six strings of four kinds of wire, increasing in strength from treble to bass”. I am also inspired by the “rules of stringing” dictated by the harper and tradition-bearer Patrick Murney in the 1880s, who dictated a 5-gauge system changing gauge every 7 strings (using a 5th gauge for the highest trebles above about g″)

This chart should work on any traditional wire-strung Irish harp; in principle I don’t see why this 4-gauge system shouldn’t also be used to string a bigger 19th century style instrument, but I have not tried this yet.


To order strings, and for video and printed instructions on fitting strings to the harp, please see my wire page.


More detailed analyses

I made detailed stringcharts available for certain standard models of harps. These are free to download:
John Egan harp string chart (2023, rev 2024)
Kildare harp stringchart (2020)
Castle Otway harp stringchart (2020)
NMI Carolan harp stringchart (2019)
Hollybrook harp stringchart (2018)
Downhill harp string chart (2018, rev 2022)
(The ones from 2020 and before show 0.75 instead of 0.8mm for the octave below na comhluighe. Perhaps it doesn’t matter, but I now think 0.8mm seems to match Murney’s list better as well as helping the harp to speak better in this important range. Some of these charts also show red brass for the lowest octave but I no longer use this, and suggest yellow brass all the way down. I also would tend to swap gauge between the sisters, instead of above them. But I think these minor differences don’t make much difference; I am just trying to always simplify the rules to help us memorise our string-lists, while following and respecting the testimony of the tradition-bearers)


If you want to read more about my thinking, and the rationale for stringing and setting up an old Irish harp in this way, you can read about this in two of my scholarly papers:
Simon Chadwick, ‘Stringing’, as part of the HHSI Hollybrook harp survey, HHSI 2021 (PDF download)
Simon Chadwick, ‘Provenance and recording of an eighteenth-century harp’, The Galpin Society Journal 73, March 2020, pages 103–5.
I have also written about speculative ideas for stringing and setup of reconstruction medieval harps (Trinity College / Brian Boru harp, Queen Mary harp, Lamont harp) These models work differently form the traditional wire-strung Irish harps.


If your harp is not one of the standard models, or you don’t know what the top and bottom note should be, I can do a string length analysis and make a custom stringchart for your harp, based on the measured string lengths. The cost of this is £20.