« torna alla gallery
Aquila Budello appesantito C

Loaded Gut Bass Strings (C type)

It can be mounted on these instruments


Lute and Baroque Guitar





basso rinascimentale

Bass (renaissance)


Violin, viola, cello

…there is another sort of strings, which they call Pistoy basses, which I conceive are none other than thick Venice-Catlins, which are commonly dyed, with a deep dark red colour.”

(Thomas Mace “Musick’s Monument” London 1676)


ATTENNTION: We would like to inform all our customers that, due to some works required for enlarging our company (new machineries, new productions etc.) we are compelled to stop production of loaded strings type “C. till April 2013 (we hope)
We are really sorry for any inconvenience this may cause you.


The appearing of wound strings caused, starting from the end of the 17th century, the definitive abandoning of the ancient manufacturing techniques of the traditional all-gut bass strings. This explains why modern plain gut strings fail to produce an acceptable acoustical performance in the low registers, thus making it unavoidable to use wound strings for musical repertoires that actually pre-date their historical appearing; this, in turn, causes an obvious philological paradox as well as serious tone and balance problems between high and low registers. A large number of bass stringhole diameters recorded from original Lute bridges dating from the late 16th and 17th century shows that those holes are too small to allow plain gut strings a sufficient working tension at the proper pitch. Musical iconography from the 17th century also shows often bass gut strings of quite different colors from that typical of plain gut, varying from dark red to brown only. Treatises of the time confirm, too, that strings possessed a remarkable duration of sound and acoustical exuberance (see: Mersenne ‘Harmonie Universelle’, Paris 1636; ‘The Mary Burwell Lute Tutor’, 1670 ca.).
All this suggests an hypothesis: the loading of gut, a technological strategy that we believe employed by the ancient string-makers in order to render the strings to be used in the low registers more sonorous.

Completely re-designed!

Special smooth roped gut strings (like ours VENICES) characterized by a high, standardized specific weight (twice than natural gut) , achieved by a loading process with metallic copper powder. Diameters smaller than 180 C are manufactured with a gradual loading decrease, in order to keep the otherwise excessive brightness of sound of the thinner strings under control and at the same time to obtain a higher tensile resistance and a longer playing life.
We DO NOT use Mercury or Lead compounds; we use metallic copper powder (not toxic)
Reddish brown color,oiled surface.


Strong and warm tone, without the excessive brightness typical of wound strings, perfectly coherent with the tone and dynamics character of gut high strings. Excellent in staying in tune, better than any plain Gut, Nylon Nylgut and wound strings available today.
Indispensable for Renaissance and Baroque stringing till the 1st half of the 17th Century, in the strictest respect to authenticity.

Hear the sound of a 11 courses d- minor lute with the loaded gut string basses


To keep calculations simple and make it possible to use any available string-calculator, C type loaded gut strings, as well as wound Nylgut ones D and DE types, are referred to by a letter following a number indicating the theoretical equivalent diameter of a plain gut string.
E. g. “140 C” stands for a loaded string (indicated by the letter “C” ) corresponding to a high twist gut of 1.40 mm. in diameter. The actual diameter of the strings is, of course, smaller but under playing conditions it will have the same working tension as a gut string of 140 mm. diameter at equal pitch.

ATTENTION: loaded strings type “C”, because of their particular complexity, may suffer of a certain uncontinuity in production. Delivery time may therefore be longer, thus delaying the shipment of other types of strings included in your order. We do apologize for any inconvenience and ensure that we are working in order to find a proper solution to avoid any problem.
Notice! These strings are made for basses only. Please do not use them as cello 1st & 2nd, Gambas 3rd & 4th; Viola da braccio 2nd.

For more information

For more information read our FAQ

PRICES FOR Loaded Gut Bass Strings (C type)

Euros excluding IVA-VAT-TVA (except for non-EU customers)

CODE Lenght (cm) Euros excluding IVA-VAT-TVA (except for non-EU customers)
112 C 120 cm only 23,10
120 C solo 120 23,10
124 C 120 cm only 26,40
132 C 120 cm only 26,40
140 C 120 cm only 31,30
150 C 120 cm only 36,10
160 C 120 cm only 36,10
170 C 120 cm only 38,80
180 C 120 cm only 38,80
190 C 120 cm only 39,00
200 C 120 cm only 43,10
210 C 120 cm only 43,10
220 C 120 cm only 43,10
240 C 120 cm only 50,70
250 C 120 cm only 50,70
270 C 120 cm only 61,60
280 C 120 cm only 61,60
300 C 120 cm only 64,00
320 C 120 cm only 68,00
340 C 120 cm only 68,00
360 C 120 cm only 72,00
380 C 120 cm only 72,00
400 C 120 cm only 74,00


a flexible loaded stringExample of a Viola da Braccio set-up  (suitable for the Monteverdi's period)7 Course LuteF. Le Troy (1690 ca.), Detail of the Charles Mouton's portraitJakob Lindberg playing his 11 Course D Minor LuteAnonymous dutch painter, 1st half of the 17th Century: detail on the brown bassesAnonymous french painter, 1st half of the 17th Century;  detail of the deep red bassesGirolamo Martinelli, 2nd half of the 17th Century: 'Concerto in casa Lazzari' (mid 17th C.)Girolamo Martinelli; detail of the violone's brown bass strings (mid 17th C.)Girolamo Martinelli; detail of the violone's brown bass strings (mid 17th C.)Girolamo Martinelli; detail on the brown bass-violin string  (mid 17th C.)Francois le Troy, 2nd half of the 17th C: detail on the brown long bassesAnonymous dutch painter, 2nd half of the 17th C; detail of the red bass strings on a 12 course luteAnonymous dutch painter, 2nd half of the 17th C; detail of the red bass strings on a 12 course luteRutilio Manetti, Siena 1625; detail on the brown Lute-bass stringsRutilio Manetti, Siena 1625; detail on the Violin brown 3rd & 4th strings  (see also: hole- measurement made on the Charles IX Andrea Amati's viol (1570 ca?). Ashmolean Museum, Oxford 2007: maximum passing diameter: 2.30 mmhole- measurement made on the Charles IX Andrea Amati's viol (1570 ca?). Ashmolean Museum, Oxford 2007: maximum passing diameter: 2.30 mm

Recent comments

Andrea Rinaudo – Italy
…mi ha stupito l’equilibrio tra bassi e cantini, cosa che permette anche di ottenere maggiori estensioni di volume con lo strumento, in registro acuto. Dal punto di vista timbrico poi sono davvero eccelse, nulla da invidiare alle…..   …le migliori corde mai provate (e non voglio far l’adulatore, non lo sono mai stato)….
David Stanley – UK
…My set of Alchemia lasted over four months without losing their tone or their volume. That is a big compliment to the strings. Other strings would occasionally last me six weeks, other strings normally only last me about two weeks!
Andrea Pettinari – ITALY
…felice che un’azienda italiana sia capace di distinguersi per professionalità e innovazione, come Voi fate.
I recently bought a few set of strings from your company. I wanted to try new strings after being loyal to my former brand for over thirty years. I must say I was pleasantly surprised in your Nylgut strings. The trebles where very nice
Phil Doleman – UK
…Anyway, as a user of your uke strings for as long as I can remember (at least 10 years I’m sure)….I’m not asking for free products, simply to share the fact that I love your strings!
Kreg Viesselman – Norway
My luthier, Leonardo Michelin-Salomon of LMS guitars, gave me a set of your strings to try on the guitar he made for me. Simply put, I love them.
Vi vorrei rivolgere i miei più sentiti complimenti per il lavoro che svolgete, e il senso di orgoglio che mi compisce nel pensare che un’azienda italiana lavori in questo modo. Ho iniziato a suonare anche grazie a Voi, e questo ve lo devo.
JUHA – Finland
Thank you very much for your kind support!!! Aquila has supported our events since we first begun and you have played a major role in helping us keep ukulele alive here……
Del Ventruella – US
…My first reaction, when I installed this strings, was to tell myself to send Aquila a message and proclaim the guy who came up with these red label strings to be a genius! (Probably tired of hearing that by now…)
Thank you for your wonderful customer service, I cannot speak highly enough of your fantastic follow up and I will continue to use Aquila strings and a lot of that has to do with the treatment I have received from you and your Company.
Rob Wright – AUSTRALIA
…I also recently bought a set of Aquila Reds for my Kala UBass which I am very happy with as well…
M° Stefano Aruta – Italy
… ieri ho ricevuto le 12 mute di AMBRA che avevo richiesto, ho montato una nuova muta e sento il bisogno di ripeterti quanto detto al telefono a mio parere sono le migliori corde oggi reperibili.
…il mio parere è frutto di una esperienza quarantacinquennale …
Innanzi tutto ho sempre insegnato ai miei allievi che la musica è l’arte di organizzare i suoni ma la matrice di tutto è il suono in sè come mero epifenomeno ed al di la di ogni banale considerazione su potenza , durata , sustain ed altre simili amenità ti ringrazio perché attraverso la tua ricerca hai ridato nobiltà al suono della chitarra , si vede che dietro al tuo lavoro non vi è solo una mera ricerca commerciale , ma un affanno teso alla ricerca del bello in modo da mettere noi musicisti in condizione di dare il meglio…
Oddbjorn Larsen – Norway
I got my Thunder reds for my Kala ubass yesterday. Put them on right away. Last night at rehearsal with my band. They all loved the tone, and for me the playability is way better than the standard strings. The deep E is loud and clear and makes it easy to make a statement for the bassist with a small bass. Thanks a lot
Michael Malley – USA
…I love the low g red series for the Ukulele. On my concert uke it works great…
Steve Paull – Australia
The new Red Aquila strings have arrived.
I have tightened the lower G string up to the B above G with no problems.
Many thanks for your kindness and great service.
Toon Van Schuylenbergh – Belgium
Hey Aquila, I’am playing ukulele for a few years now and I’am in love with Aquila strings. I always use Aquila strings…
M° Domenico Lafasciano
Ho avuto il piacere di provare le corde armoniche Aquila.
Ottimo prodotto, con perfetta intonazione, bellissima cantabilità, prontezza d’attacco,
fascino nel vibrato.
Inoltre la loro lunghezza e morbidezza, rendono anche piacevole il noioso lavoro del cambio
di corde.
Le userò e le raccomando vivamente !
M° Massimo Gasbarroni – Italy
Come le accennavo frettolosamente, anch’io come, credo, tutti i chitarristi di questo mondo, abbiamo sempre avuto il problema di reperire delle corde di chitarra con delle prestazioni meccaniche e sonore accettabili.
Quando ero studente, fine anni quaranta-cinquanta ho provato anche le corde di budello e di seta naturalmente.
Ma se andavano bene per piccoli spazi non erano certo adatte ad una moderna sala da concerto, come ad esempio il Teatro Petruzzelli, 3000 posti, dove tenni un concerto senza problemi.
Sembrerebbe, a meno di un colossale abbaglio, che con le sue corde io possa aver finito di soffrire…
Michael Curry – USA
Alabastro, basses were nice and round, with plenty of edge to cut through, a very good string with lots of volume….
Nylgut- Extremely dynamic string, these are loud with better tone than carbon strings, all the brightness one would ever wantI would keep them on 2 of my 5 guitars though, because the grip on them is amazing, the unbelievable dynamic range, and they are warmer than carbon…. I must admit, I have been using very clear nylon strings over the yearsso nylgut was a nice in-between alternative, I think I will buy more in the future for sure..
The Bionylon felt great under my fingers, and I loved the sustain when I would do a glissando.
David Stanley – UK
On Nylgut strings…Many listeners have commented on their beautiful clear sound.
These are the best strings I have used in over 50 years of performing & teaching.
Seoung Don Min
We’re so satisfied with your product.
Thank you for everything and honored I like this nice bright tone and rapid attack response.
also I think (as you written down the back of the pack) tone stability is quite nice
Eventually I got my banjo tuned to standard G tuning….
I had to shorten a couple of the strings because of too many wraps around the tuner post, but now it stays in tune.
I love these Nylgut strings…
John Kelly – USA
…I have used your strings for years and love them…
…ok, your loaded long gut string is the best from long time.So am am waiting until you can…
Taro Tamura – Japan
I have web shop ”Spain Guitar Online Shop” in Japan. I have sell mainly Classical guitars,Flamenco guitars and Ukes. I am interested in your ukuleles strings. It’s fantastic.
Guys! I have just strung my soprano,concert and banjouke with your red strings, they are awesome! The sound is rich, the tonation beautiful and the low G for the concert uke is a wonder to behold. My instruments have never sounded so good. I thought my other Aquila strings were good…..but these…..WOW! My brother-in-law also plays uses and I have bought him two sets also. Thank you sooooo much for making these strings
Ann Beckett – AUSTRALIA
It is rare these days to find the dedication to customers’ needs by yourself and your Company and I absolutely applaud you for this, not too many companies would go out of their way to help like you have, rather they would dismiss it as just not worth the effort….Aquila have just been absolutely outstanding in offering help….
James Everhart – USA
…I thank you very much for your service. As well as the quality of your product. I am a fan of Aquila strings for life.My ukulele says thank you very much! Have a Great Day!
Castellaro Davide – The Utopia Custom shop – Italy
… In questo periodo diversi miei clienti mi chiedono i Vostri prodotti…
George Charalampidis – Greece
…I love the sound of Aquila’s Nylgut for Oud and I do not want to buy strings from another company…
M° Marcello Appignani
I have tried a lot of different brands of guitar strings but I never heard a sound so fitting to me! I am an ”anomalous” guitarist because I play also on the piano so I cannot have long nails and with the classical guitar strings Alabastro I got the sound I looked for.
Julian Roach – UK
… After two weeks of playing on them every day I am still delighted with them….I find them molto cantabile, with excellent sustain, quick in their response and highly responsive to variation in touch. They bring a new kind of sound out of my Sakurai-Kohno, a very ’alive’ kind of sound. I normally play on D’Addario Pro Arte, which I regard both as excellent strings and good value. Alabastros cost a lot more, but I will pay the difference for their distinctive charm. I thought you might like to know that you have a customer in the UK who is very pleased with your strings…
Andre Hendriks – NL
A ukuleleshop is not complete whitout Aquila strings
Salvatore Pinto – ITALY
…sono bellissime, grazie. siete stati molto gentili continuerò a usare queste corde.
Manuals Sales conditions safety certifications Aquila 4 Community