I have tried a number of brands and sets of strings, to find which best suit playing without nails. I’ve paid for all these strings myself, so I have no relationship with the companies mentioned.
Latest Update 3rd July, 2017:
I must put my cards on the line and say that I think the best gut strings for classical guitar currently on the market are made by Damian Dlugolecki of http://damianstrings.com
Damian recently improved his strings, and they now tune to A=440, modern pitch, and will happily tune to A=435 for Tárrega. Here’s a video I made after the strings had been on my Simon Ambridge guitar (after Manuel Ramirez) for only 24 hours:
Update to what you can read below:
I’ve very recently tried plain unvarnished gut from the harp-string specialists in the UK, Bow Brand. So far so good. The shortest length they supply is 4ft, which leaves about one foot of wastage, which is a shame. However, they also supply 12ft lengths at a discount, which provides four strings – very useful. Living in the UK, this cuts down on postage and import duty, which is appreciated. You have to write to them (via their Contact page) for a pdf price list, before making an order. Here’s a couple of videos using Bow Brand first (0.66), second (0.80), and a Damian Dlugolecki third string:
Update: These strings have surprised me by lasting over
two six months. The quality of production is excellent, and when purchased in 12-foot lengths, are as economical as nylon equivalents. Recommended.
Another piece of news is that Damian Dlugolecki is sending me one or two of his varnished gut strings for comparison. A review will follow. Update: They came. They went. Not for me. However, my cyber friend, Kacper Wierzchos, loves them, and he too plays without nails.
My favourite gut trebles are made by Damian Dlugolecki of Damian Strings in the US.
He offers plain or varnished gut. I only like the plain variety. These strings should last a long time, especially when only played with the flesh of the finger tip. They are beautiful strings to touch, and the sound is warm. Recommended. He offers them as single purchases, or as part of a set. However, his basses are modern synthetic strings.
Here’s a video with the three treble strings from Damian Dlugolecki:
La Bella Antique Gut Strings
Available as a gut set, or with modern basses. I tried these once. They lasted a week. Very poor quality compared to those above or below. Not recommended.
Aquila Gut and Silk 900
Aquila have changed their Gut & Silk strings from when I first played them. Initially I liked them, but with recent set, only the basses were useable. The three treble strings were very rough, and had intonation problems. Disappointing . From the Aquila website: “This set which is made with only one degree of tension, riproposes excatly a historical assembling, tipycal of the period of Llobet and Tàrrega by using only genuine gut strings for Trebles and silk’s core wound basses, as it was said by Pujol in the “Escuela Razonada de la Guitarra” of 1934.” Pujol gave measurements for the strings he used, which Aquila have taken for their production of these strings.
One possible downside to using this set is that they cannot be tuned to modern pitch of A = 440. Best tune them a semitone lower. If you like loud, strident, cutting basses, look elsewhere. The basses here are soft-sounding, and with little sustain, but I find them beautifully balanced with gut trebles – I’d say they are the best bass strings on the market at the moment.
Aquila Ambra 900
Aquila have produced two types of nylgut (nylon with some properties of gut), now referred to as Old Nylgut and New Nylgut. This set has trebles made from the Old Nylgut, which is milk-white in colour, and very smooth in texture. That said, the Aquila website mentions New Nylgut, or “Supernylgut®”. The set I currently have is of the Old Nylgut variety. The basses use Aquila’s own invention: Sylkgut cores.
I’d like to say at the outset that I don’t believe that using nylgut is anywhere close to the experience of playing real gut, but it is probably the best alternative we have today. The sound, though, is warm, less bright than modern strings.
Ambra 2000 seems to be an update of the 900 series: “This set was conceived for one grade of tension and consists of -gut coloured Super Nylgut® for Trebles, while for the basses (silvered copper wires wound on Nylgut® multifilament core) we employed a different balance between wire and core in order to obtain warm and deep performances”. The New Nylgut used here has the colour of gut (yellowish). The tuning settles much faster than before. I just wish they weren’t so smooth. With flesh contact, it helps to a little bit of traction. Talking of which…
Savarez Low Tension (“White Card”)
The trebles are ever so slightly rough, not nearly enough to cause a rough sound, but just enough to give good contact with the flesh. They are also much louder than the Aquila brands. When I first put them on, there was quite a bit of noise generated by the right-hand fingers sliding along the string, but as the days go by, that sound decreased. They have a nice warmth, treble and bass, and the low tension means I can control vibrato better.