As suppliers of replacement strings we often get very confused requests for replacement strings.

Although pedal harps and folk harps based on pedal harp tension strings are generally fairly straight forward, many folk harps present a different situation.  
Most folk harp makers design their own strings and even different models from the same maker generally require different strings.
Any nylon wrapped strings as commonly found on folk harps have to be made specifically for a given harp or at least a given vibrating length as they cannot be cut to size.
Each harp is designed to take a specific set of strings and the soundboard is specifically designed for the tension of those strings.  Using strings other than those recommended by the harp maker will in most cases void the warranty.  Strings with heavier tension create a greater stress on the harp and soundboard while those with a lighter tension may not damage the harp but in most cases will compromise the sound.  
For pedal harp and folk harps based on concert tension gut strings these harps are designed around the “standard” strings which are sold by octave and note, such as 3rd octave B etc. Most folk harps when sold include a string list for that harp.  
In the case of harps that we make and those from Dusty Strings, an extra copy of the string list is also attached to the back of the soundboard.  
To add more variables, some folk harps are designed for “standard” folk harp nylon strings.  Many European string vendors do offer “standard” strings which can be ordered by octave and note.
Where confusion often arises is that the nomenclature for octaves on a harp differs from those of a piano and for that matter also that of chromatic tuners.
Harps have their own unique designation for octaves. This evolved from the early harps such as those from Erard which had an E for the highest note and so that was designated as string number 1 and octave 1.
The first octave then became E down to F.  The next octave started again with E so the change of octaves occurred between F and E.  
However, piano octaves change at C and start with octave 1 being the lower notes and octave 7 the highest (plus some minor extensions for those technically inclined).  
To add to the confusion, harp octave designation then was modified as additional strings where added above the original top E.  These notes then became string number 0 and 00.  
Over time, two more strings were also added in the base but these were simply added to the original 7th octave E. Interestingly, middle C is 4th octave C with both systems.
When we get string orders we therefore need to clarify to make sure that the customer knows the correct harp octave nomenclature when they order by octave and note.
When ordering replacement strings for folk harps, unless you know the gauge, often the easiest way to avoid confusion is to order by string number and harp model.  String number one being the shortest string.  In our case, we keep string lists from many makers on file.
Then of course there are different types of strings, such as gut, nylon, rectified nylon, steel, bronze and numerous synthetics such as NylGut and Fluorocarbon (sometimes incorrectly called carbon fibre).
Some harps come designed for these alternative types of strings and with calculations it is often possible to safely substitute types of strings.  
When someone calls and wants a replacement string for the “A an octave below middle C on a Celtic harp”, you can see why we need more information.
I hope that you find this background information helpful and has not added to the confusion. We have produced a handy chart which lists typical string numbers and the corresponding harp and piano octaves.
If you would like a copy send an email to This email address is being protected from spambots. You need JavaScript enabled to view it.  or click here
Questions and comments for future “Harp Workbench” columns of this newsletter can be addressed.